feat(fleet): enhancer role + two-agent floor (orchestrator + enhancer) (#614)

From Jason's north-star (docs/fleet/north-star.md, #613): every fleet has a
two-agent floor — orchestrator + enhancer minimum. Builds on #612's init-R5.

- Presets (general/coding/research/hybrid): add enhancer (claude, class:
  enhancer, persistent_persona) as a core always-on agent. minimal/local-canary
  unchanged.
- fleet.ts: countEnhancers helper; init guarantee extended — non-minimal
  profiles must yield exactly 1 orchestrator AND >=1 enhancer (hard-fail);
  removeAgentFromRoster refuses to drop the sole enhancer (symmetric with the
  sole-orchestrator guard) so the floor holds at runtime, not just init.
- framework/fleet/roles/enhancer.md: the enhancer mandate (monitor -> analyze ->
  plan -> upgrade tools/skills/harness WITH orchestrator -> file Mosaic Stack
  bug reports) + boundaries (does NOT code or review).

Verified: 155 fleet tests green (countEnhancers; sole-enhancer remove guard;
remove-allows-when-another; init two-agent-floor; every-non-minimal-preset-has-
enhancer; updated preset rosters). tsc/eslint/prettier/sanitize clean. TDD on
the init guarantee + remove protection.

Stacked on #612 (feat/fleet-polish-bundle); rebases clean onto main after #612.

Refs #614, #613

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EsgTQzV5YUGk1JtCLP4B83

.woodpecker/ci.yml

@@ -25,12 +25,10 @@ steps:
     commands:
       - apk add --no-cache bash
       - bash packages/mosaic/framework/tools/quality/scripts/verify-sanitized.sh
-      # L0 resident-token budget: keep the Constitution + dispatcher small.
+      # Resident line-count ceiling over framework-owned resident files
-      - |
+      # (Constitution + dispatcher + each RUNTIME.md slice). See DESIGN §7 / R9.
-        for f in CONSTITUTION.md AGENTS.md; do
+      - bash packages/mosaic/framework/tools/quality/scripts/check-resident-budget.sh --self-test
-          n=$(wc -l < "packages/mosaic/framework/defaults/$f")
+      - bash packages/mosaic/framework/tools/quality/scripts/check-resident-budget.sh
-          if [ "$n" -gt 120 ]; then echo "L0 budget exceeded: defaults/$f is $n lines (max 120)"; exit 1; fi
-        done
 
   typecheck:
     image: *node_image

docs/TASKS.md

@@ -45,3 +45,24 @@ Active workstream is **W1 — Federation v1**. Workers should:
 - Status: PR open, awaiting maintainer merge ratification (fleet-governing change).
 - Cut always-injected contract AGENTS+TOOLS+RUNTIME 8,827→4,122 tok (−53%); all 12 hard gates intact.
 - Validation: deterministic gate-checklist PASS; headless A/B thin 7/9 vs monolith 5/9. Detail: scratchpads/contract-thin-core.md.
+
+## P5 — Overlay composer + cross-harness (#604) — feat/p5-overlay-composer
+
+- Status: MERGED to main (#605). R7 (compose-contract) + R8 (cross-harness) + R9 (composer test).
+- `composeContract({harness, mosaicHome})` pure fn + `.local` overlay deltas-by-value; `mosaic compose-contract <harness>` command; AGENTS bare-launch nudge; composer spec (per-tier anchor + Tier-3 byte-equality). Detail: scratchpads/p5-overlay-composer.md.
+
+## P6 — Docs, compliance matrix, alpha tag (#606) — feat/p6-docs-compliance-alpha
+
+- Status: in-repo deliverables done (CONTRIBUTING.md + harness×gate compliance matrix + check-resident-budget.sh + CI wiring + ALPHA-DOD.md). Remaining: alpha tag v0.0.39-alpha (Lead, post-merge). aiguide reconcile merged (#8). Detail: scratchpads/p6-docs-compliance-alpha.md.
+
+## F3-m3 — mosaic update re-seeds framework + relaunches agents (#609) — feat/f3-m3-update-reseed
+
+- Status: implemented + tested. Closes R13: `mosaic update` now re-seeds the framework (data-safe MOSAIC_SYNC_ONLY) after the CLI install so shipped launcher/runtime changes activate; `--relaunch` restarts rostered agents; `--no-reseed` opts out. Detail: scratchpads/f3-m3-update-reseed.md.
+
+## Fleet-polish bundle — boot-survival symmetry (#611) — feat/fleet-polish-bundle
+
+- Status: implemented + tested. disable-on-remove (boot-resurrection bug, TDD) + add-enable + init-R5 hard guarantee. 4 new + 147 existing fleet tests green. Detail: scratchpads/fleet-polish-bundle.md.
+
+## Fleet enhancer role + two-agent floor (#614) — feat/fleet-enhancer-floor (stacked on #612)
+
+- Status: implemented + tested. enhancer added to 4 presets; init guarantees 1 orchestrator + >=1 enhancer; remove protects the sole enhancer; enhancer role doc. 155 fleet tests green. Detail: scratchpads/fleet-enhancer-floor.md.

docs/design/framework-constitution/ALPHA-DOD.md

@@ -0,0 +1,75 @@
+# Constitution Alpha — Definition-of-Done checklist + release notes
+
+Drafted for the `v0.0.39-alpha` tag (Lead cuts after P5 #605 → P6 #607 → aiguide #8 merge).
+Maps every DoD §8 acceptance criterion to its merged evidence. Legend:
+**✅ merged on main** · **⏳ review-ready PR (pending merge)** · **🔲 Lead action**.
+
+## DoD §8 green-checklist
+
+| #   | Acceptance criterion (DESIGN §8)                                                                       | Status | Evidence / PR     |
+| --- | ------------------------------------------------------------------------------------------------------ | ------ | ----------------- |
+| 1   | MIT `LICENSE` (root + framework) + `"license":"MIT"` in package.json                                   | ✅     | P0 #570           |
+| 2   | Three credential-path sites + hook URL fast-failed (no private paths in `*.sh`/hooks)                  | ✅     | P0 #570           |
+| 3   | `verify-sanitized.sh` (two-class, `*.sh`+`*.md`, self-tested) wired **blocking** in CI                 | ✅     | P1 #572           |
+| 4   | Operator data purged from the full set (guides / tools / init-generator)                               | ✅     | P2 #572           |
+| 5   | `rails/`→`tools/` in **both** template families                                                        | ✅     | P2 #572           |
+| 6   | `jarvis-loop.json` deleted; `defaults/SOUL.md` → **neutral sanitized persona** (Q10 decision)          | ✅     | P2 #572           |
+| 7   | `CONSTITUTION.md` extracted (gates one place, capability-verb, §1.4 split, no false "already loaded")  | ✅     | P3 #575 / #577    |
+| 8   | `AGENTS.md`/`STANDARDS.md` out of `PRESERVE_PATHS` + seed-semantics → overwrite in **both** installers | ✅     | P4 #590           |
+| 9   | Snapshot + v2→v3 migration moving user edits to `.local`/`.bak`; `FRAMEWORK_VERSION=3`                 | ✅     | P4 #590 / #593    |
+| 10  | `mosaic-init --non-interactive` fail-closed persona                                                    | ✅     | P4 #590           |
+| 11  | **5-fixture migration matrix** green against **both** installers asserting **injected bytes**          | ✅     | P4 #590 / #593    |
+| 12  | `compose-contract` built + composer unit test (per-tier anchor + Tier-3 byte-equality)                 | ⏳     | P5 #605           |
+| 13  | Resident line-count ceiling enforced (framework-owned resident files)                                  | ⏳     | P6 #607           |
+| 14  | `CONTRIBUTING.md` + harness×gate compliance matrix                                                     | ⏳     | P6 #607           |
+| 15  | `aiguide` reconciled with the Constitution                                                             | ⏳     | aiguide #8        |
+| 16  | Each phase PR CI-green; alpha tag pushed + Gitea release published                                     | 🔲     | Lead (post-merge) |
+
+**Note on #6:** the DoD's literal "delete `defaults/SOUL.md`" was superseded by the resolved
+**Q10** decision — ship a _neutral, operator-agnostic_ example persona instead of deleting it. Main
+carries the sanitized 2.6 KB neutral SOUL.md ("Mosaic agent", no operator identity); the sanitization
+gate confirms it is PII-clean. Criterion met in spirit (no operator persona leaks) via the better option.
+
+**Gate to flip 12–14 → ✅:** merge P5 #605 → P6 #607 (rebase auto-drops the dup format fix
+`adc7df2`/`9f6da92`) → aiguide #8, with `ci.yml` terminal-green on the merged head.
+
+---
+
+## Release notes — `v0.0.39-alpha` (Mosaic Framework Constitution, alpha)
+
+### Mosaic Framework Constitution — Alpha
+
+This release makes the Mosaic framework a **safe-to-open-source, fork-and-customize agent
+operating layer**. It separates the non-negotiable law from operator identity, makes
+customization survive upgrades, and wires the guarantees into CI.
+
+**Highlights**
+
+- **Constitution (L0).** The hard gates now live in one place — `CONSTITUTION.md` — authored in
+  capability verbs, with a thin `AGENTS.md` dispatcher that references the law instead of restating
+  it. Governance model in `constitution/LAYER-MODEL.md`.
+- **Public & sanitized.** MIT-licensed; all operator identity, private paths, and credential sites
+  removed from shipped files. A self-tested `verify-sanitized.sh` gate (two rule classes) runs
+  **blocking** in CI so re-contamination can't merge.
+- **Upgrade-safe customization.** Framework-owned files overwrite cleanly on upgrade while
+  `SOUL.md`/`USER.md`/`*.local.md`/`credentials` are preserved. The v2→v3 migration snapshots first
+  and moves any user-edited `AGENTS.md`/`STANDARDS.md` to `.pre-constitution.bak`/`.local.md` —
+  never silently lost. Verified by a 5-fixture matrix across **both** installers.
+- **Operator overlays.** `mosaic compose-contract <harness>` merges your `*.local.md` deltas into
+  the contract per harness, so customization reaches the model as one pre-merged blob.
+- **Cross-harness.** Single L0 source referenced (never restated) by Claude / Codex / OpenCode / Pi;
+  tiered injection with a byte-equal Tier-3 fallback read.
+- **Guardrails in CI.** Resident line-count ceiling over framework-owned resident files; composer
+  unit test; sanitization gate — all blocking.
+- **Docs.** `CONTRIBUTING.md` with the layer model, dual-installer parity rule, and a harness×gate
+  **compliance matrix** (the Codex/OpenCode/Pi hook-parity gap is tracked for v2).
+
+**Known limitations (accepted, documented in `CONTRIBUTING.md` §9)**
+
+- Bare launches that bypass `mosaic` get base contracts only (no `*.local` overlays) and are not
+  drift-checked by `mosaic doctor` — mitigated by the unconditional Tier-3 self-load + a nudge.
+- Codex/OpenCode/Pi mechanical hook parity, `policy/*.md` composition, and live-launch cross-harness
+  verification are **v2**.
+
+**Phase lineage:** P0 #570 · P1+P2 #572 · P3 #575/#577 · P4 #590/#593 · P5 #605 · P6 #607 ·
+aiguide #8 (umbrella #542).

docs/fleet/PRD-fleet-suite.md

@@ -0,0 +1,109 @@
+# PRD — Mosaic Fleet Suite (init, configure, operate)
+
+> **Workstream:** W-FLEET (Fleet) under mission `mvp-20260312` · **Phase:** 3→4 productization
+> **North star:** [docs/fleet/north-star.md](./north-star.md) · prior: Phase-2 observability (#579), durable launch (#581), real-agent enablement (#583/#584/#586), releases 0.0.35–0.0.37
+> **Lead:** Jarvis @ `w-jarvis`. **Collaborator:** coder agent @ `dragon-lin` (jwoltje@10.1.10.37:coder0-0).
+> Owner of this file: Fleet workstream lead. Does not modify MVP single-writer control-plane files.
+
+## Mission
+
+Turn the proven fleet primitives into a **user-installable, AI-free-configurable fleet product**:
+a user runs `mosaic fleet init`, answers a few questions (general / coding / research / hybrid),
+gets a recommended set of agents plus one always-on orchestrator wired for chat-ops, and can
+operate, mutate, re-create, and observe the fleet — over tmux today and Matrix tomorrow — from
+CLI/TUI and (designed-for) the webUI.
+
+**Immediate tangible goal:** the **"Mos"** orchestrator agent running on `w-jarvis`, reachable
+in **Discord channel `1517622518662434996`** (server `1112631390438166618`). Once the fleet is
+functional, we use the fleet itself to continue the work.
+
+## Requirements
+
+### A. Configure-without-AI CLI
+
+| ID  | Requirement                                                                                                   |
+| --- | ------------------------------------------------------------------------------------------------------------- |
+| R1  | `mosaic fleet` command set is functional end-to-end (init/install/start/stop/status/ps/verify + agent verbs). |
+| R2  | `mosaic fleet init` is an interactive, **AI-free** CLI wizard.                                                |
+| R3  | Init asks the **configuration type**: `general`, `coding`, `research`, `hybrid`, … (extensible).              |
+| R4  | Based on the answer, the fleet is populated with a **recommended set of agents** (a preset).                  |
+| R5  | **Exactly one main orchestrator agent** is always configured, regardless of type.                             |
+| R10 | A set of **recommended configurations (presets)** ships for easy duplication.                                 |
+| R8  | User can **re-create** the fleet when config needs change (idempotent re-init / reconfigure).                 |
+| R17 | Fleet controls are **simple and intuitive**.                                                                  |
+
+### B. Comms & orchestrator chat-ops
+
+| ID  | Requirement                                                                                                                       |
+| --- | --------------------------------------------------------------------------------------------------------------------------------- |
+| R6  | Init can wire the orchestrator to a chat connector — **Telegram / Discord / Matrix / Slack** — for command + comms.               |
+| R7  | Designed with the end-goal of **Matrix comms on a locally-controlled server**.                                                    |
+| R16 | Fleet supports **tmux AND Matrix** comms, **user-configurable** at init or any time. Not all users want Matrix.                   |
+| R19 | **"Mos" orchestrator on Discord** (`chan 1517622518662434996` / `srv 1112631390438166618`) on `w-jarvis` — the first live target. |
+
+### C. Runtime, health, lifecycle
+
+| ID  | Requirement                                                                        |
+| --- | ---------------------------------------------------------------------------------- |
+| R9  | Fleet is **mutable by the orchestrator agent** — add/remove agents per need.       |
+| R13 | Fleet **gracefully handles Pi + Claude harness updates** — keep harnesses current. |
+| R14 | The **Pi harness is customized** for proper tool usage, etc.                       |
+| R15 | **Agent heartbeat** properly configured for **Claude AND GPT/Pi** agents.          |
+
+### D. Surfaces, testing, docs
+
+| ID  | Requirement                                                                         |
+| --- | ----------------------------------------------------------------------------------- |
+| R18 | Fleet built so the **webUI can view / monitor / terminate / butt-in** on a session. |
+| R11 | Installed and **tested on both `w-jarvis` and `dragon-lin`**.                       |
+| R12 | **Documentation**: how to install, configure, and use the fleet.                    |
+
+## Architecture / approach
+
+- **Config model:** `roster.yaml` is the source of truth (already exists). Add **presets** (`general`/`coding`/`research`/`hybrid`) as shipped example rosters; `init` selects a preset, always injects the orchestrator, and writes the roster. Re-init = regenerate roster (preserve user/site overrides — mirrors install env-merge from #567).
+- **Orchestrator agent:** always present; carries the chat connector config (connector type + target IDs) so it can be commanded over chat. tmux is the substrate; the connector bridges chat ↔ the orchestrator session.
+- **Comms layers (R16):** (1) **tmux** inter-agent (`agent-send`, proven) — default, always available. (2) **chat connector** for human↔orchestrator (Discord now; Matrix the strategic target). (3) **Matrix** as the locally-controlled cross-agent bus (future). Connector is pluggable + reconfigurable.
+- **Heartbeat (R15):** runtime-agnostic launcher sidecar already covers pi/claude/codex (#584). Refine per-runtime (native HB) with the **custom Pi harness** (R14) + a Claude path.
+- **Updates (R13):** `mosaic update` (CLI) + a fleet-aware harness-update step that refreshes pi/claude/codex and re-launches agents safely (drain → update → relaunch via the durable launcher).
+- **webUI (R18):** the fleet exposes machine-readable state (`fleet ps --json` already carries tenant/host/heartbeat/managed) + control verbs (start/stop/watch/send); webUI consumes these (control plane rides federation per north star). Ensure a stable JSON contract + a terminate/attach(butt-in) path.
+
+## Phases (incremental, each shippable)
+
+| Phase                             | Deliverable                                                                                                                         | Notes                                 |
+| --------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------- |
+| **F1 Presets + init wizard**      | preset rosters (general/coding/research/hybrid) + always-orchestrator + AI-free `fleet init` selecting a preset; re-init idempotent | R1–R5, R8, R10, R17                   |
+| **F2 Connector + Mos-on-Discord** | orchestrator chat-connector config (Discord first) + **Mos live on Discord `1517…`/`1112…`** on w-jarvis                            | R6, R19, partial R16                  |
+| **F3 Heartbeat + harness**        | HB confirmed for claude + pi/gpt; **custom Pi harness** (tool usage, native HB, model self-report); graceful harness updates        | R13, R14, R15                         |
+| **F4 Matrix + comms toggle**      | Matrix connector (local server) + user toggle tmux/Matrix at init/anytime                                                           | R7, R16                               |
+| **F5 Orchestrator-mutable fleet** | orchestrator can add/remove agents at runtime                                                                                       | R9                                    |
+| **F6 webUI hooks**                | stable JSON contract + terminate/attach surface for webUI view/monitor/terminate/butt-in                                            | R18                                   |
+| **F7 Test + docs**                | install+test on w-jarvis AND dragon-lin; user docs (install/configure/use)                                                          | R11, R12 (runs alongside every phase) |
+
+## Work division (proposed — confirm with dragon-lin)
+
+- **Jarvis @ w-jarvis (Lead):** F1 presets+wizard, F2 connector+Mos-on-Discord, F5 mutability, F6 webUI hooks; merge authority + dual-engine reviews; co-testing on w-jarvis.
+- **coder @ dragon-lin:** F3 custom Pi harness + harness-update flow (pi/codex-savvy); plus its in-flight constitution P4–P6 (P4 installer rework underpins `fleet init`/updates — coordinate the install path). Co-testing on dragon-lin (R11).
+- **Shared:** F4 Matrix (whoever has bandwidth); F7 testing/docs continuous.
+
+## Immediate target: Mos on Discord (F2 first slice)
+
+The discord plugin is available (`~/.claude.json`). Path: configure the **orchestrator** as a durable
+fleet session running Claude Code with the discord plugin bridged to channel `1517622518662434996`
+(server `1112631390438166618`) on w-jarvis, with the existing Discord Bridge Protocol (ack within
+~3s, reply via `mcp__discord__reply`, no `AskUserQuestion`). Heartbeat via the launcher sidecar.
+
+## Success criteria
+
+- A non-AI user can `mosaic fleet init`, pick a type, and get a working fleet + orchestrator.
+- **Mos answers in Discord `1517…`** on w-jarvis.
+- Fleet runs + is observable (`fleet ps`) on **both** w-jarvis and dragon-lin.
+- Harness updates handled gracefully; HB healthy for claude + pi/gpt agents.
+- Docs let a new operator install/configure/use the fleet.
+- Re-init + orchestrator mutation work.
+
+## Assumptions (veto-able)
+
+- `ASSUMPTION:` presets ship as example rosters under the framework (`fleet/examples/*.yaml`), selected by `init`.
+- `ASSUMPTION:` chat connectors are pluggable; Discord first (target exists), Matrix is the strategic default later.
+- `ASSUMPTION:` "Mos" = a Claude Code orchestrator session with the discord plugin (reuses the documented Discord Bridge Protocol).
+- `ASSUMPTION:` per north star, runtimes default to Codex/pi-on-Codex for workers; the orchestrator "Mos" runs Claude Code (in Claude Code, which is allowed).

docs/fleet/north-star.md

@@ -115,6 +115,11 @@ Every artifact, starting Phase 2, MUST:
 - Observation: **read-only default, opt-in takeover**.
 - Multi-host: **designed-for from day one**; control plane **rides federation (W1)**.
 - Delivery: **CLI-first now**, dogfood against the live stub fleet; webUI deferred to Phase 5.
+- Runtimes: fleet agents default to **Codex / pi-on-Codex**; **Claude is reserved for Claude
+  Code only** (avoid alternate-harness API pricing). Validated durable recipe:
+  `mosaic yolo pi --model openai-codex/gpt-5.5:high`. Durable detached launch requires the
+  runtime-bin on PATH (baked into the pane command) + boot-survival (`enable` + linger),
+  which `fleet init` should automate.
 
 ## Assumptions (veto-able)
 

docs/scratchpads/f3-m3-update-reseed.md

@@ -0,0 +1,29 @@
+# F3-m3 — `mosaic update` re-seeds framework + relaunches agents (R13)
+
+- **Issue:** #609 · **Branch:** `feat/f3-m3-update-reseed`
+
+## Gap (found in 0.0.39 production validation)
+
+`mosaic update` installs the new npm CLI but never re-seeds `~/.config/mosaic/` from the package's
+bundled `framework/`. So the shipped custom Pi harness (agent-name export + native HB, 0.0.39) stays
+DORMANT until a re-seed — operators get the new CLI on a stale framework.
+
+## Implementation
+
+- `update-checker.ts`: `resolveBundledFrameworkRoot()`, `buildReseedCommand()` (install.sh in
+  `MOSAIC_SYNC_ONLY=1 MOSAIC_INSTALL_MODE=keep` — the P4 data-safe reconcile), `runFrameworkReseed()`,
+  `readRosterAgentNames()`, `buildRelaunchCommands()` (systemctl --user restart per agent).
+- `cli.ts` `update`: after a successful CLI install that includes `@mosaicstack/mosaic`, re-seed the
+  framework (default-on; `--no-reseed` to skip). Then either `--relaunch` (restart rostered agents) or
+  print clear guidance to run `mosaic update --relaunch` / `mosaic fleet restart`.
+
+## Flow
+
+`update CLI → re-seed framework (data-safe) → relaunch agents (opt-in)` — closes R13, activates the
+native harness for every operator.
+
+## Verification
+
+- 6 new unit tests (reseed command/env, relaunch commands, roster parse, missing-installer guard).
+- 19 runtime + 26 launch tests still green; tsc/eslint/prettier clean.
+- Data-safety of the sync is already proven (P4 5-fixture matrix + live dragon-lin validation).

docs/scratchpads/fleet-enhancer-floor.md

@@ -0,0 +1,26 @@
+# Fleet enhancer role + two-agent floor (#614)
+
+- **Issue:** #614 · **Branch:** `feat/fleet-enhancer-floor` (stacked on #612 `feat/fleet-polish-bundle`)
+- **Doctrine:** `docs/fleet/north-star.md` (PR #613) — every fleet = orchestrator + enhancer minimum.
+
+## Changes
+
+- **Presets** (general, coding, research, hybrid): add `enhancer` (claude, `class: enhancer`,
+  `persistent_persona: true`) as a core always-on agent alongside the orchestrator. minimal/local-canary
+  unchanged.
+- **fleet.ts**: `countEnhancers` helper; init guarantee extended — non-minimal profiles must yield
+  exactly 1 orchestrator AND >=1 enhancer (hard-fail otherwise); `removeAgentFromRoster` refuses to drop
+  the sole enhancer (symmetric with the sole-orchestrator guard) so the floor holds at runtime, not just init.
+- **Role doc**: `framework/fleet/roles/enhancer.md` — the enhancer mandate (monitor → analyze → plan →
+  upgrade tools/skills/harness WITH orchestrator → file Mosaic Stack bug reports) + boundaries (does NOT
+  code or review).
+
+## Verification
+
+- 155 fleet tests green (new: countEnhancers; remove-sole-enhancer guard; remove-allows-when-another;
+  init two-agent-floor; every-non-minimal-preset-has-enhancer; updated preset rosters). tsc/eslint/
+  prettier/sanitize clean. TDD on the init guarantee + remove protection.
+
+## Stacking
+
+Built on #612's init-R5 code. PR shows #612 + enhancer until #612 merges; then rebase onto main → clean.

docs/scratchpads/fleet-observability-phase2.md

@@ -73,3 +73,28 @@ with a second agent on `dragon-lin`.
      tmux session-name fallback; the systemd/tmux env handoff needs a real fix.
 - Next: rebase on merged main, open Phase-2 PR, dual-engine review, merge, close
   `fleet-observability-1`. Defer launch-path + env-propagation fixes to Phase 3.
+- 2026-06-21 (session 3): Phase-2 PR #579 merged (3 dual-engine rounds hardened
+  verify+watch). Then closed the launch-path question with Jason's input — CORRECTING
+  earlier findings:
+  - The ad-hoc launch deaths were NOT a fundamental TTY blocker: (a) codex was a stale
+    version (Jason updated it); (b) pi was misconfigured to Claude auth (Jason removed it;
+    default is now Codex). The REAL durable-launch bug is **PATH**: the detached tmux
+    launch shell is login+non-interactive, so it misses `~/.npm-global/bin` (added only in
+    `~/.bashrc`) -> `mosaic: command not found` (127) -> pane dies. tmux panes inherit the
+    tmux _server_ env, so PATH must be baked into the pane command.
+  - **Durable real-agent recipe (validated live on gpt-5.5, Claude-free):**
+    `mosaic yolo pi --model openai-codex/gpt-5.5:high` — pi tolerates detached tmux; a raw
+    interactive TUI (codex CLI) exits without an attached client. Status line confirmed
+    `(openai-codex) gpt-5.5 • high`.
+  - PATH fix landed in `start-agent-session.sh` (commit 32efc13, branch
+    feat/fleet-launch-path): derive runtime-bin prefix (MOSAIC_RUNTIME_BIN | npm prefix |
+    ~/.npm-global/bin | ~/.local/bin), bake `export PATH=...; exec <cmd>` into the pane;
+    `exec` also fixes the drift false-positive. Live-tested under stripped PATH -> durable.
+  - Boot-survival: Jason ran `systemctl --user enable` (+ linger). TODO: auto-enable in
+    **fleet init** so operators never have to remember it (agentic-enhancement cycle).
+  - Future custom Pi harness build: pi cannot self-report its model (track
+    runtime/model/effort as fleet metadata); drift detection should recognize `node` as
+    pi's pane command (a node-wrapped pane can currently read as drift).
+  - Findings recorded in AI Guide playbooks/tmux-fleet.md (aiguide PR #7, merged).
+  - Policy: avoid Claude outside Claude Code (API pricing for alt-harness use) — fleet
+    runtimes default to Codex / pi-on-Codex; Claude stays in Claude Code only.

docs/scratchpads/fleet-polish-bundle.md

@@ -0,0 +1,20 @@
+# Fleet-polish bundle — boot-survival symmetry (#611)
+
+- **Issue:** #611 · **Branch:** `feat/fleet-polish-bundle` · From the Lead's Codex symmetry-gap finding.
+
+## Three fixes
+
+1. **disable-on-remove (BUG, TDD).** `fleet remove` stopped + deleted roster/env/heartbeat but never
+   `systemctl --user disable mosaic-agent@NAME.service` → a removed-but-enabled unit could resurrect on
+   reboot pointing at deleted config. Fix: `buildSystemdDisableCommand` + disable in `remove`
+   (best-effort, gated on !--keep-files).
+2. **add-enable.** `fleet add` now enables the new agent's unit for boot-survival (best-effort,
+   independent of --start) — symmetry with disable-on-remove.
+3. **init-R5 guarantee.** `fleet init --write` now FAILS HARD when a non-minimal profile doesn't yield
+   exactly one orchestrator (was a soft warning). `minimal` (sanctioned no-orchestrator) still allowed.
+
+## Verification
+
+- 4 new tests (disable builder; remove-invokes-disable; add-invokes-enable; init general → exactly 1
+  orchestrator) + 147 existing fleet tests green (151 total). tsc/eslint/prettier clean.
+- TDD on the disable bug per contract.

docs/scratchpads/p5-overlay-composer.md

@@ -0,0 +1,43 @@
+# P5 — Overlay composer + cross-harness (compose-contract)
+
+- **Issue:** #604 · **Branch:** `feat/p5-overlay-composer` · **Lineage:** #542 → constitution alpha
+- **Requirements:** R7 (compose-contract) + R8 (cross-harness) + R9 (composer test)
+- **Design of record:** `docs/design/framework-constitution/{DESIGN.md §3.2, PRD.md §4}` (on `feat/framework-constitution-alpha`)
+
+## Locked design (sequential-thinking)
+
+Current `launch.ts` assembly (`buildComposedPrompt`) injects by value: mission + PRD + hard-gate +
+CONSTITUTION + AGENTS + USER + TOOLS + runtime. It does **not** inject SOUL or STANDARDS (those are
+read-on-demand per the gutted AGENTS dispatcher), and has no `.local` overlay support.
+
+**Decision (ASSUMPTION — recorded for the PR):** overlays are injected as **deltas by value** under
+labeled sections; base files keep their existing residency.
+
+- `USER.local.md` → appended directly under the `# User Profile` block (USER is injected).
+- `SOUL.local.md` + `STANDARDS.local.md` → a trailing `# Operator Overlays` section (their bases are
+  load-on-demand, so only the small delta is injected — not the full base prose).
+- **Why:** honors DESIGN §3.2 ("model gets one pre-merged blob, no read-merge ritual") while preserving
+  the P3 byte-budget tiering (don't re-inject large SOUL/STANDARDS prose). Precedence order kept: base
+  layers first, operator overlays at recency.
+- Base-only is automatic when a `.local` file is absent (`readOptional`).
+
+## Plan
+
+| #   | Task                                                                                                   | File                                    |
+| --- | ------------------------------------------------------------------------------------------------------ | --------------------------------------- |
+| 1   | Extract `composeContract({harness, mosaicHome})` pure fn; `buildComposedPrompt` delegates              | `src/commands/launch.ts`                |
+| 2   | Overlay logic (USER.local under profile; SOUL/STANDARDS.local in `# Operator Overlays`)                | `src/commands/launch.ts`                |
+| 3   | `mosaic compose-contract <harness>` command → prints blob to stdout                                    | `src/commands/launch.ts`                |
+| 4   | Bare-launch overlay nudge in self-load fallback                                                        | `framework/defaults/AGENTS.md`          |
+| 5   | `compose-contract.spec.ts`: per-tier anchor, Tier-3 byte-equality, overlay present/absent, per-harness | `src/commands/compose-contract.spec.ts` |
+
+## Deferred to P6
+
+CONTRIBUTING.md + harness×gate compliance matrix; resident line-count CI ceiling; `aiguide` reconcile;
+alpha tag `mosaic-vX.Y.Z-alpha`.
+
+## Status
+
+- [x] Phase scaffold (branch, issue #604, scratchpad, TASKS)
+- [ ] Implementation (tasks 1–5)
+- [ ] prettier + vitest green; PR via wrapper → Lead (rides 0.0.39; 0.0.38 mid-cut)

docs/scratchpads/p6-docs-compliance-alpha.md

@@ -0,0 +1,29 @@
+# P6 — Docs, compliance matrix, alpha tag (constitution capstone)
+
+- **Issue:** #606 · **Branch:** `feat/p6-docs-compliance-alpha` · **Lineage:** #542
+- **Requirements:** R9 (resident line-count ceiling) + R10 (CONTRIBUTING + compliance matrix + aiguide) + alpha tag
+
+## Delivered (in-repo)
+
+- `framework/CONTRIBUTING.md` — layer model, operator-hygiene/PII prohibition, dedup rule, resident
+  budget, **dual-installer parity rule**, adding-a-harness, re-contamination rule, **harness×gate
+  compliance matrix** (hook-parity gap marked ⚠️ tracked-v2), known-limitations (§9 residuals), PR checklist.
+- `framework/tools/quality/scripts/check-resident-budget.sh` — line-count ceiling over framework-owned
+  resident files (CONSTITUTION + AGENTS + each runtime/\*/RUNTIME.md); `--self-test`; replaces the crude
+  inline ci.yml loop. Wired blocking in `.woodpecker/ci.yml`.
+- Composer unit test (R9) already runs via `pnpm test`; `verify-sanitized.sh` (P1) already wired.
+
+## Verification
+
+- Sanitization gate green (CONTRIBUTING is operator-neutral). Resident-budget self-test + real run green.
+- prettier clean. Current resident counts: CONSTITUTION 96, AGENTS 83, RUNTIME max 75 — all < ceiling.
+
+## Remaining
+
+- [ ] `aiguide` reconcile (separate repo `~/src/aiguide` / mosaicstack/aiguide) — consistency pass vs Constitution.
+- [ ] Alpha tag `mosaic-vX.Y.Z-alpha` — propose version; Lead cuts after full DoD §8 green + all phases merged.
+
+## Notes
+
+- Alpha DoD (DESIGN §8): all phases P0–P6 merged + CI green. P5 (#605) pending merge after 0.0.38 publish.
+- Hook parity (codex/opencode/pi) = tracked v2 gap, documented in the matrix, not closed here.

packages/mosaic/framework/CONTRIBUTING.md

@@ -0,0 +1,185 @@
+# Contributing to the Mosaic Framework
+
+The Mosaic framework is the open-source agent-operating layer that deploys to
+`~/.config/mosaic/`. It is designed to be **forked and customized** — but the
+shared core must stay operator-neutral, deduplicated, and upgrade-safe. This
+guide is the contract for changing framework-owned files.
+
+> Governance model and layer rationale: `constitution/LAYER-MODEL.md` (source-only).
+> Requirements & phase history: `docs/design/framework-constitution/`.
+
+---
+
+## 1. The layer model (where does my change go?)
+
+| Layer  | What                                                          | Owner            | On upgrade                              | File(s)                                      |
+| ------ | ------------------------------------------------------------- | ---------------- | --------------------------------------- | -------------------------------------------- |
+| **L0** | Constitution — the non-negotiable law (hard gates)            | Framework        | **Overwritten**                         | `CONSTITUTION.md`                            |
+| **L1** | Standards & guides — how to do the work well                  | Framework        | Overwritten; user delta → `*.local.md`  | `STANDARDS.md`, `guides/*`                   |
+| **L2** | Persona (SOUL) — agent name, tone, role                       | User (init)      | **Never overwritten**                   | `SOUL.md` (+ optional `SOUL.local.md`)       |
+| **L3** | Operator (USER) — human identity, prefs, policy               | User (init)      | **Never overwritten**                   | `USER.md` (+ optional `USER.local.md`)       |
+| **L4** | Project / runtime mechanism — per-repo deltas; harness wiring | Repo / framework | Project user-owned; runtime overwritten | `<repo>/AGENTS.md`, `runtime/<h>/RUNTIME.md` |
+
+**The one sentence a user can rely on:** edit `SOUL.md` / `USER.md` and the
+`.local.md` overlays — they survive every upgrade. To change framework behavior,
+add a `.local.md` overlay; never edit a framework-owned file in place.
+
+---
+
+## 2. Operator hygiene (PII / secrets prohibition) — **blocking**
+
+Framework-owned files ship publicly. They **must not** contain:
+
+- Operator or personal identity (names, handles, pronouns, accessibility notes).
+- Private `$HOME` paths, private hostnames, or domains.
+- Secrets, tokens, or credentials (use `~/.config/mosaic/credentials.json`; the
+  hook URL soft-degrades via `${OPENBRAIN_URL}`).
+
+This is enforced by `tools/quality/scripts/verify-sanitized.sh`, wired **blocking**
+in CI (`.woodpecker/ci.yml`). It runs two rule classes: structural (private-`$HOME`
+defaults, dead paths, unrendered tokens) and a labeled current-contaminant denylist.
+Run it locally before pushing:
+
+```bash
+bash packages/mosaic/framework/tools/quality/scripts/verify-sanitized.sh
+```
+
+Operator-specific behavior belongs in **your** `SOUL.md`/`USER.md`/`*.local.md`,
+never in the shared core. (The "framework-PR firewall" in `CONSTITUTION.md` §4
+states this as law for agents opening framework PRs.)
+
+---
+
+## 3. Dedup rule — one source, everyone references it
+
+Hard gates live in **`CONSTITUTION.md` (L0) only**. `AGENTS.md`, `STANDARDS.md`,
+and every `runtime/<h>/RUNTIME.md` **reference** the law — they never restate it.
+Restating a gate is a defect: it creates two sources that drift. If you find a
+gate duplicated outside L0, delete the copy and point to L0.
+
+`AGENTS.md` is a thin dispatcher (load order + guide router + the tier-aware
+self-load). Keep it that way; new procedure goes in `guides/*` (on-demand), not
+in the resident core.
+
+---
+
+## 4. Resident line-count ceiling — **blocking**
+
+The framework-owned files injected by value (`CONSTITUTION.md`, `AGENTS.md`, each
+`runtime/<h>/RUNTIME.md`) are budgeted by **line count** — never by word count
+(a word cap forces paraphrasing the law, the exact drift vector we removed).
+
+```bash
+bash packages/mosaic/framework/tools/quality/scripts/check-resident-budget.sh
+```
+
+Wired blocking in CI. Gate **wording** stays intact; if a file legitimately needs
+more lines, raise its ceiling in the script deliberately (in the same PR, with
+rationale). The per-harness _total_ resident prompt (which also sums the user's
+`SOUL.md`/`USER.md`) is a `mosaic doctor` runtime advisory — CI cannot see user
+files, so it is out of CI scope by design (DESIGN §7).
+
+---
+
+## 5. Dual-installer parity rule
+
+Two installers seed and migrate `~/.config/mosaic/`:
+
+- **`framework/install.sh`** (bash) — the canonical installer.
+- **`packages/mosaic/src/config/file-adapter.ts`** (TS) — the wizard path.
+
+**Any change to seed lists, overwrite/preserve semantics, or migration MUST land
+in BOTH**, validated by the **shared fixture suite**:
+
+- `framework/tools/quality/scripts/test-install-migration.sh` (bash matrix)
+- `packages/mosaic/src/config/file-adapter.test.ts` (vitest)
+
+Both assert the same behavior: framework-owned files overwrite (backup-once to
+`*.pre-constitution.bak`); user-seeded files seed-if-absent; `SOUL.md`/`USER.md`/
+`*.local.md`/`credentials` are preserved. A change in one installer without the
+other (and its fixtures) is incomplete.
+
+---
+
+## 6. Adding a harness adapter
+
+A harness (runtime) is wired by:
+
+1. `runtime/<h>/RUNTIME.md` — **mechanism only** (subagent syntax, hook/MCP wiring,
+   injection method). No restated gates (see §3).
+2. Launcher emission in `src/commands/launch.ts` — how the composed contract reaches
+   the harness (system-prompt append vs. instructions file). Add the harness to the
+   `RuntimeName` union and the runtime-path map.
+3. `mosaic compose-contract <harness>` works automatically once the runtime path
+   exists (it composes base + `*.local.md` overlays for that harness).
+
+Then add a row to the compliance matrix (§8) and mark which gates are mechanical
+vs. resident-only for the new harness.
+
+---
+
+## 7. Re-contamination rule
+
+A green sanitization gate is not permanent. Before every PR:
+
+- Do not reintroduce operator identity, private paths, or secrets (§2).
+- Do not copy a gate out of L0 (§3).
+- Do not add an unrendered template token or a dead path to a shipped file.
+
+If `verify-sanitized.sh` goes red, that diff **is** your worklist — fix it, don't
+suppress it.
+
+---
+
+## 8. Harness × gate compliance matrix
+
+How each gate is enforced per harness. **Mechanical** = a hook/CI check the agent
+cannot bypass. **Resident** = injected contract prose (strong, but not a hard stop).
+**CI** = repo-side, harness-independent.
+
+| Gate / mechanism                              | Claude      | Codex            | OpenCode         | Pi               |
+| --------------------------------------------- | ----------- | ---------------- | ---------------- | ---------------- |
+| Contract injection (resident-by-value)        | append SP   | instructions     | `AGENTS.md`      | append SP        |
+| Operator overlays (`*.local`, composed)       | ✅          | ✅               | ✅               | ✅               |
+| Bare-launch self-load (Tier-3, read L0)       | ✅          | ✅               | ✅               | ✅               |
+| Sanitization (no PII) — `verify-sanitized`    | CI ✅       | CI ✅            | CI ✅            | CI ✅            |
+| Resident budget ceiling                       | CI ✅       | CI ✅            | CI ✅            | CI ✅            |
+| Migration parity (5-fixture, both installers) | CI ✅       | CI ✅            | CI ✅            | CI ✅            |
+| `no-memory-write` (PreToolUse hook)           | **mech ✅** | resident-only ⚠️ | resident-only ⚠️ | resident-only ⚠️ |
+| QA / typecheck (PostToolUse hooks)            | **mech ✅** | resident-only ⚠️ | resident-only ⚠️ | resident-only ⚠️ |
+| Native heartbeat (fleet `ps` model/status)    | sidecar     | sidecar          | sidecar          | **native ✅**    |
+
+⚠️ **Hook-parity gap (tracked, v2):** the mechanical PreToolUse/PostToolUse hooks
+exist for Claude Code only. On Codex/OpenCode/Pi those gates are currently enforced
+by the resident contract + CI, not by a per-tool hook. Closing hook parity is a
+**v2** item, not part of this alpha.
+
+---
+
+## 9. Known limitations (accepted residual risks)
+
+These are accepted with rationale (DESIGN §9); they are documented, not bugs:
+
+- **Bare-launch overlays are base-only.** A harness started without `mosaic` never
+  ran the composer, so `*.local.md` overlays are not applied. Mitigated by the
+  unconditional Tier-3 self-load + the `mosaic doctor` nudge in `AGENTS.md`; not
+  eliminated. Relaunch via `mosaic <harness>` to pick up overlays.
+- **Bare-launch drift is undetected by `mosaic doctor`** (the launcher never ran).
+- **Codex/OpenCode/Pi hook parity** is a tracked v2 gap (§8).
+- **Live-launch cross-harness verification** is v2; the alpha verifies the composer
+  by unit test (per-tier anchor + Tier-3 byte-equality), not a live launch.
+
+**Deferred to v2 (explicit):** `constitution/` deploy directory; capability JSON
+adapters; 3-way merge; `policy/*.md` composition; per-layer version stamps as a
+migration driver.
+
+---
+
+## 10. PR checklist
+
+- [ ] No operator identity / private paths / secrets (`verify-sanitized.sh` green).
+- [ ] No gate restated outside `CONSTITUTION.md` (§3).
+- [ ] Resident budget green (`check-resident-budget.sh`).
+- [ ] Seed/migration changes landed in **both** installers + shared fixtures (§5).
+- [ ] New harness → compliance-matrix row updated (§8).
+- [ ] `prettier --check` + `pnpm lint` + `pnpm typecheck` + `pnpm test` green.

packages/mosaic/framework/defaults/AGENTS.md

@@ -9,7 +9,10 @@ overwritten on upgrade. (Layer model: `constitution/LAYER-MODEL.md`.)
 1. Your context already includes `CONSTITUTION.md` + `USER.md` + the TOOLS index + the runtime
    contract (injected by `mosaic` launch) — do not re-read those. **If you were launched bare**
    (a harness started without `mosaic`, so the law is NOT in your context), read
-   `~/.config/mosaic/CONSTITUTION.md` now, before your first action.
+   `~/.config/mosaic/CONSTITUTION.md` now, before your first action. A bare launch also gets
+   **base contracts only** — operator overlays (`*.local.md`) are composed by the launcher, so if
+   `SOUL.local.md`/`USER.local.md`/`STANDARDS.local.md` exist, relaunch via `mosaic <harness>` (or run
+   `mosaic doctor`) to pick them up.
 2. Read `SOUL.md` (agent persona — small, once).
 3. Read project-local `AGENTS.md` / `CLAUDE.md` if present (these may only make behavior stricter).
 4. Read guides ONLY as triggered by the table below — pull role-relevant depth on demand, not up front.
@@ -70,6 +73,9 @@ Skills, hooks, MCP, and plugins are force multipliers you MUST use when applicab
 ## Missing core file
 
 If `CONSTITUTION.md`, `AGENTS.md`, `SOUL.md`, or the runtime contract is missing, stop and report it.
+This agent-facing strictness is intentional and stricter than the launcher: the launcher injects
+`CONSTITUTION.md` tolerantly (skipping it if absent so pre-upgrade hosts keep working), but once a host
+is re-seeded a genuinely missing core file is a stop-and-report condition — not something to proceed past.
 
 ## Session Closure
 

packages/mosaic/framework/defaults/CONSTITUTION.md

@@ -2,8 +2,11 @@
 
 The irreducible, non-negotiable law for every Mosaic agent on every harness.
 
-**Framework-owned.** This file is overwritten verbatim on every upgrade — do not edit it. To change
+**Framework-owned.** This file is overwritten verbatim on every upgrade — do not edit it. There is
-behavior, add a `.local.md` overlay or a `policy/` file (tighten-only; see `constitution/LAYER-MODEL.md`).
+**no `CONSTITUTION.local.md`**: hard gates are not locally overridable. A lower layer may only make
+behavior _stricter_, never relax or override a gate (see Precedence). Operator customization lives in
+other layers — `SOUL.md` / `USER.md` and the tighten-only overlays `STANDARDS.local.md` /
+`SOUL.local.md` / `USER.local.md` / `policy/*.md` (see `constitution/LAYER-MODEL.md`).
 Authored in **capability verbs**: where a gate names a capability ("structured reasoning", "queue
 guard"), the runtime adapter binds it to a concrete tool and states whether absence is a hard stop.
 

packages/mosaic/framework/fleet/examples/coding.yaml

@@ -0,0 +1,36 @@
+version: 1
+transport: tmux
+tmux:
+  socket_name: mosaic-factory
+  holder_session: _holder
+defaults:
+  working_directory: ~
+runtimes:
+  claude:
+    reset_command: /clear
+  pi:
+    reset_command: /new
+agents:
+  - name: orchestrator
+    runtime: claude
+    class: orchestrator
+    persistent_persona: true
+  - name: enhancer
+    runtime: claude
+    class: enhancer
+    persistent_persona: true
+  - name: coder0
+    runtime: pi
+    class: implementer
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: coder1
+    runtime: pi
+    class: implementer
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: reviewer
+    runtime: pi
+    class: reviewer
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true

packages/mosaic/framework/fleet/examples/general.yaml

@@ -0,0 +1,26 @@
+version: 1
+transport: tmux
+tmux:
+  socket_name: mosaic-factory
+  holder_session: _holder
+defaults:
+  working_directory: ~
+runtimes:
+  claude:
+    reset_command: /clear
+  pi:
+    reset_command: /new
+agents:
+  - name: orchestrator
+    runtime: claude
+    class: orchestrator
+    persistent_persona: true
+  - name: enhancer
+    runtime: claude
+    class: enhancer
+    persistent_persona: true
+  - name: generalist
+    runtime: pi
+    class: worker
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true

packages/mosaic/framework/fleet/examples/hybrid.yaml

@@ -0,0 +1,36 @@
+version: 1
+transport: tmux
+tmux:
+  socket_name: mosaic-factory
+  holder_session: _holder
+defaults:
+  working_directory: ~
+runtimes:
+  claude:
+    reset_command: /clear
+  pi:
+    reset_command: /new
+agents:
+  - name: orchestrator
+    runtime: claude
+    class: orchestrator
+    persistent_persona: true
+  - name: enhancer
+    runtime: claude
+    class: enhancer
+    persistent_persona: true
+  - name: coder0
+    runtime: pi
+    class: implementer
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: researcher0
+    runtime: pi
+    class: researcher
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: reviewer
+    runtime: pi
+    class: reviewer
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true

packages/mosaic/framework/fleet/examples/research.yaml

@@ -0,0 +1,36 @@
+version: 1
+transport: tmux
+tmux:
+  socket_name: mosaic-factory
+  holder_session: _holder
+defaults:
+  working_directory: ~
+runtimes:
+  claude:
+    reset_command: /clear
+  pi:
+    reset_command: /new
+agents:
+  - name: orchestrator
+    runtime: claude
+    class: orchestrator
+    persistent_persona: true
+  - name: enhancer
+    runtime: claude
+    class: enhancer
+    persistent_persona: true
+  - name: researcher0
+    runtime: pi
+    class: researcher
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: researcher1
+    runtime: pi
+    class: researcher
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true
+  - name: analyst
+    runtime: pi
+    class: analyst
+    model_hint: openai-codex/gpt-5.5:high
+    reset_between_tasks: true

packages/mosaic/framework/fleet/roles/enhancer.md

@@ -0,0 +1,41 @@
+# Enhancer — fleet role definition
+
+The **enhancer** is one half of the fleet's two-agent floor: every fleet runs, at
+minimum, an **orchestrator** and an **enhancer**. The orchestrator drives delivery;
+the enhancer makes the fleet _get better at delivering_ over time.
+
+It is a **core, always-on** agent (`class: enhancer`, `persistent_persona: true`),
+not an ephemeral per-lane worker.
+
+## Mandate
+
+The enhancer runs the fleet's **continuous-improvement loop**:
+
+1. **Monitor** fleet activity — agents, heartbeats, sessions, throughput, failures.
+2. **Analyze** for enhancements and optimizations — friction, gaps, recurring defects,
+   missing or broken tools, skill/harness shortfalls.
+3. **Plan** a remediation: a concrete improvement with rationale and expected effect.
+4. **Upgrade fleet capability — with the orchestrator** — tool creation/repair, skills,
+   harness improvements. The orchestrator owns fleet composition; the enhancer advises and
+   implements improvements to the _means of production_, not the product.
+5. **File upstream bug reports** to Mosaic Stack for real defects, so they flow back to the
+   framework for proper remediation rather than being patched over locally.
+6. **Recommend which agents are needed** — advise the orchestrator on roles to add/remove as
+   the mission evolves.
+
+## Boundaries
+
+- **Does NOT write product/source code.**
+- **Does NOT review code** (that is the code-review / security-review roles).
+- **Does NOT perform delivery tasks.**
+
+Improvement and diagnosis only. When the enhancer finds work that requires coding or review,
+it files it (bug report / recommendation) and the orchestrator materializes the right worker.
+
+## Why two, not one
+
+The orchestrator alone optimizes for _this_ delivery; the enhancer optimizes for _every future_
+delivery — self-healing the fleet's tools, skills, and harnesses, and routing real defects
+upstream. Together they are the irreducible core; every other role is added on demand.
+
+> Doctrine: `docs/fleet/north-star.md` (two-agent floor + role library).

packages/mosaic/framework/install.sh

@@ -19,13 +19,23 @@ SOURCE_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 TARGET_DIR="${MOSAIC_HOME:-$HOME/.config/mosaic}"
 INSTALL_MODE="${MOSAIC_INSTALL_MODE:-prompt}"
 
-# Files/dirs preserved across upgrades (never overwritten).
+# Files/dirs protected from rsync --delete during sync. NOTE: framework-owned
+# entries (CONSTITUTION/AGENTS/STANDARDS) ARE re-applied afterward by
+# reconcile_framework_files (overwrite + backup-once); the rest stay user-owned.
 # User-created content in these paths survives rsync --delete.
-PRESERVE_PATHS=("AGENTS.md" "SOUL.md" "USER.md" "TOOLS.md" "STANDARDS.md" "memory" "sources" "credentials")
+PRESERVE_PATHS=("CONSTITUTION.md" "AGENTS.md" "SOUL.md" "USER.md" "TOOLS.md" "STANDARDS.md" "memory" "sources" "credentials")
+
+# Framework-owned contract files: re-copied from defaults/ on every upgrade (the
+# user must not edit them; a divergent copy is backed up once before overwrite).
+# USER_SEEDED files are written once on first install, then owned by the user.
+# Both lists are APPEND-FRIENDLY — add a new shipped framework file here and to the
+# matching list in packages/mosaic/src/config/file-adapter.ts.
+FRAMEWORK_OWNED=("CONSTITUTION.md" "AGENTS.md" "STANDARDS.md")
+USER_SEEDED=("TOOLS.md")
 
 # Current framework schema version — bump this when the layout changes.
 # The migration system uses this to run upgrade steps.
-FRAMEWORK_VERSION=2
+FRAMEWORK_VERSION=3
 
 # ─── colours ──────────────────────────────────────────────────────────────────
 if [[ -t 1 ]]; then
@@ -40,6 +50,47 @@ warn() { echo -e "  ${YELLOW}⚠${RESET} $1" >&2; }
 fail() { echo -e "  ${RED}✗${RESET} $1" >&2; }
 step() { echo -e "\n${BOLD}$1${RESET}"; }
 
+# ─── snapshot / restore (crash safety for upgrades) ──────────────────────────
+SNAPSHOT_DIR=""
+make_snapshot() {
+  is_existing_install || return 0
+  SNAPSHOT_DIR="$(mktemp -d "${TMPDIR:-/tmp}/mosaic-snapshot-XXXXXX")"
+  cp -a "$TARGET_DIR/." "$SNAPSHOT_DIR/" 2>/dev/null || true
+}
+restore_snapshot() {
+  [[ -n "$SNAPSHOT_DIR" && -d "$SNAPSHOT_DIR" ]] || return 0
+  fail "Install interrupted/failed — restoring previous state from snapshot"
+  rm -rf "$TARGET_DIR"; mkdir -p "$TARGET_DIR"
+  cp -a "$SNAPSHOT_DIR/." "$TARGET_DIR/" 2>/dev/null || true
+}
+cleanup_snapshot() { [[ -n "$SNAPSHOT_DIR" && -d "$SNAPSHOT_DIR" ]] && rm -rf "$SNAPSHOT_DIR"; SNAPSHOT_DIR=""; }
+
+# Reconcile contract files after sync: framework-owned overwrite (backup-once),
+# user-seeded seed-if-absent.
+reconcile_framework_files() {
+  local defaults="$TARGET_DIR/defaults" f
+  [[ -d "$defaults" ]] || return 0
+  for f in "${FRAMEWORK_OWNED[@]}"; do
+    [[ -f "$defaults/$f" ]] || continue
+    # Already current — skip to avoid mtime churn.
+    if [[ -f "$TARGET_DIR/$f" ]] && cmp -s "$TARGET_DIR/$f" "$defaults/$f"; then
+      continue
+    fi
+    if [[ -f "$TARGET_DIR/$f" && ! -f "$TARGET_DIR/${f}.pre-constitution.bak" ]]; then
+      cp "$TARGET_DIR/$f" "$TARGET_DIR/${f}.pre-constitution.bak"
+      warn "$f is now framework-owned and was updated; your previous copy is saved as ${f}.pre-constitution.bak — re-apply intended changes as a .local overlay or policy/ file (see CONSTITUTION.md / constitution/LAYER-MODEL.md)."
+    fi
+    cp "$defaults/$f" "$TARGET_DIR/$f"
+  done
+  for f in "${USER_SEEDED[@]}"; do
+    [[ -f "$defaults/$f" ]] || continue
+    if [[ ! -f "$TARGET_DIR/$f" ]]; then
+      cp "$defaults/$f" "$TARGET_DIR/$f"
+      ok "Seeded $f from defaults"
+    fi
+  done
+}
+
 # ─── helpers ──────────────────────────────────────────────────────────────────
 
 is_existing_install() {
@@ -113,11 +164,14 @@ sync_framework() {
   fi
 
   if command -v rsync >/dev/null 2>&1; then
-    local rsync_args=(-a --delete --exclude ".git" --exclude ".framework-version")
+    local rsync_args=(-a --delete --exclude ".git" --exclude ".framework-version" --exclude "*.pre-constitution.bak")
 
     if [[ "$INSTALL_MODE" == "keep" ]]; then
+      # Anchor to the transfer root (leading /) so we preserve the TOP-LEVEL
+      # ~/.config/mosaic/<file> without also excluding defaults/<file> from sync
+      # (reconcile_framework_files needs the freshly-synced defaults/ copies).
       for path in "${PRESERVE_PATHS[@]}"; do
-        rsync_args+=(--exclude "$path")
+        rsync_args+=(--exclude "/$path")
       done
     fi
 
@@ -137,7 +191,7 @@ sync_framework() {
     done
   fi
 
-  find "$TARGET_DIR" -mindepth 1 -maxdepth 1 ! -name ".git" ! -name ".framework-version" -exec rm -rf {} +
+  find "$TARGET_DIR" -mindepth 1 -maxdepth 1 ! -name ".git" ! -name ".framework-version" ! -name "*.pre-constitution.bak" -exec rm -rf {} +
   cp -R "$SOURCE_DIR"/. "$TARGET_DIR"/
   rm -rf "$TARGET_DIR/.git"
 
@@ -195,10 +249,15 @@ run_migrations() {
     fi
   fi
 
-  # ── Future migrations go here ──────────────────────────────────────────────
+  # ── Migration: v2 → v3 (Constitution split) ───────────────────────────────
-  # if [[ "$from_version" -lt 3 ]]; then
+  # CONSTITUTION.md / AGENTS.md / STANDARDS.md become framework-owned (overwritten
-  #   ...
+  # on upgrade). reconcile_framework_files() has already run before this point: it
-  # fi
+  # backed up any user-edited copy to <file>.pre-constitution.bak and installed the
+  # new framework version. Nothing further to do here — the advisory was emitted at
+  # reconcile time. (STANDARDS.local.md composition lands with the overlay composer.)
+  if [[ "$from_version" -lt 3 ]]; then
+    ok "Migrated to the Constitution layout (framework-owned CONSTITUTION/AGENTS/STANDARDS)"
+  fi
 }
 
 # ═══════════════════════════════════════════════════════════════════════════════
@@ -216,29 +275,25 @@ else
   ok "Install mode: overwrite"
 fi
 
+# Snapshot before any destructive file operation; restore on interrupt/failure.
+make_snapshot
+trap 'restore_snapshot' ERR INT TERM
+
 sync_framework
 
 # Ensure persistent directories exist
 mkdir -p "$TARGET_DIR/memory"
 mkdir -p "$TARGET_DIR/credentials"
 
-# Seed defaults — copy framework contract files from defaults/ to framework
+# Reconcile contract files from defaults/ into the framework root: framework-owned
-# root if not already present. These ship with sensible defaults but must
+# files (CONSTITUTION/AGENTS/STANDARDS) are overwritten every upgrade (a divergent
-# never be overwritten once the user has customized them.
+# copy is backed up once); user-seeded files (TOOLS) are written on first install only.
 #
 # This list must match the framework-contract whitelist in
 # packages/mosaic/src/config/file-adapter.ts (FileConfigAdapter.syncFramework).
 # SOUL.md and USER.md are intentionally NOT seeded here — they are generated
 # by `mosaic init` from templates with user-supplied values.
-DEFAULTS_DIR="$TARGET_DIR/defaults"
+reconcile_framework_files
-if [[ -d "$DEFAULTS_DIR" ]]; then
-  for default_file in CONSTITUTION.md AGENTS.md STANDARDS.md TOOLS.md; do
-    if [[ -f "$DEFAULTS_DIR/$default_file" ]] && [[ ! -f "$TARGET_DIR/$default_file" ]]; then
-      cp "$DEFAULTS_DIR/$default_file" "$TARGET_DIR/$default_file"
-      ok "Seeded $default_file from defaults"
-    fi
-  done
-fi
 
 # Ensure tool scripts are executable
 find "$TARGET_DIR/tools" -name "*.sh" -exec chmod +x {} + 2>/dev/null || true
@@ -249,6 +304,18 @@ ok "Framework synced to $TARGET_DIR"
 # Run migrations before post-install (migrations may remove old bin/ etc.)
 run_migrations
 
+# File-system phase complete and consistent — clear the restore trap.
+trap - ERR INT TERM
+cleanup_snapshot
+
+# Testability / minimal-install hook: stop after the file-system phase, before any
+# environment-touching post-install steps (runtime linking, MCP setup, skills, doctor).
+if [[ "${MOSAIC_SYNC_ONLY:-0}" == "1" ]]; then
+  write_framework_version
+  ok "Sync-only mode: file phase complete"
+  exit 0
+fi
+
 step "Post-install tasks"
 
 SCRIPTS="$TARGET_DIR/tools/_scripts"

packages/mosaic/framework/runtime/pi/mosaic-extension.ts

@@ -9,8 +9,16 @@
  *   4. Memory routing — remind agent to use ~/.config/mosaic/memory/
  */
 
-import type { ExtensionAPI } from '@mariozechner/pi-coding-agent';
+import type { ExtensionAPI, ExtensionContext } from '@earendil-works/pi-coding-agent';
-import { existsSync, readFileSync, writeFileSync, unlinkSync, mkdirSync } from 'node:fs';
+import { Type } from 'typebox';
+import {
+  existsSync,
+  readFileSync,
+  writeFileSync,
+  unlinkSync,
+  mkdirSync,
+  renameSync,
+} from 'node:fs';
 import { join, basename } from 'node:path';
 import { homedir } from 'node:os';
 import { execSync, spawnSync } from 'node:child_process';
@@ -25,6 +33,57 @@ const MOSAIC_HOME = process.env['MOSAIC_HOME'] ?? join(homedir(), '.config', 'mo
 // Helpers
 // ---------------------------------------------------------------------------
 
+// ---------------------------------------------------------------------------
+// Native heartbeat (fleet R14/R15)
+// ---------------------------------------------------------------------------
+// When this agent runs under the Mosaic fleet (MOSAIC_AGENT_NAME set), the
+// extension writes its OWN heartbeat in the same .hb contract `fleet ps` reads
+// (ts/pid/status[/model]) and touches a `.hb.native` precedence marker so the
+// shell sidecar defers. Native HB knows the real turn state (busy/ok), so it is
+// more accurate than the pane-PID-only sidecar fallback.
+const HB_AGENT_NAME = process.env['MOSAIC_AGENT_NAME'] ?? '';
+const HB_RUN_DIR = process.env['MOSAIC_HEARTBEAT_RUN_DIR'] ?? join(MOSAIC_HOME, 'fleet', 'run');
+const HB_INTERVAL_MS = (() => {
+  const s = Number.parseInt(process.env['MOSAIC_HEARTBEAT_INTERVAL'] ?? '', 10);
+  return Number.isFinite(s) && s > 0 ? s * 1000 : 15_000;
+})();
+
+function nativeHbEnabled(): boolean {
+  return HB_AGENT_NAME.length > 0;
+}
+
+function readModelId(ctx: ExtensionContext): string | null {
+  const m = ctx.model as unknown as { id?: string; name?: string } | undefined;
+  return m?.id ?? m?.name ?? null;
+}
+
+function writeNativeHeartbeat(status: 'ok' | 'busy', model: string | null): void {
+  if (!nativeHbEnabled()) return;
+  try {
+    mkdirSync(HB_RUN_DIR, { recursive: true });
+    const hb = join(HB_RUN_DIR, `${HB_AGENT_NAME}.hb`);
+    const lines = [`ts=${nowIso()}`, `pid=${process.pid}`, `status=${status}`];
+    if (model) lines.push(`model=${model}`);
+    const tmp = `${hb}.tmp.${process.pid}`;
+    writeFileSync(tmp, lines.join('\n') + '\n');
+    renameSync(tmp, hb); // atomic replace — fleet ps never reads a partial file
+    // Precedence marker: tells the shell sidecar that native HB is authoritative.
+    writeFileSync(join(HB_RUN_DIR, `${HB_AGENT_NAME}.hb.native`), nowIso() + '\n');
+  } catch {
+    // Best-effort: never let heartbeat I/O disrupt the Pi session.
+  }
+}
+
+function clearNativeMarker(): void {
+  if (!nativeHbEnabled()) return;
+  try {
+    const m = join(HB_RUN_DIR, `${HB_AGENT_NAME}.hb.native`);
+    if (existsSync(m)) unlinkSync(m); // native stopping — let the sidecar take over
+  } catch {
+    /* ignore */
+  }
+}
+
 function safeRead(filePath: string): string | null {
   try {
     return readFileSync(filePath, 'utf-8');
@@ -187,6 +246,9 @@ function buildMissionSummary(cwd: string, mission: ActiveMission): string {
 
 export default function register(pi: ExtensionAPI) {
   let sessionCwd = process.cwd();
+  let hbStatus: 'ok' | 'busy' = 'ok';
+  let hbModel: string | null = null;
+  let hbTimer: ReturnType<typeof setInterval> | null = null;
 
   // ── Session Start ─────────────────────────────────────────────────────
   pi.on('session_start', async (_event, ctx) => {
@@ -207,10 +269,39 @@ export default function register(pi: ExtensionAPI) {
     } else {
       ctx.ui.notify('Mosaic framework loaded', 'info');
     }
+
+    // Native heartbeat: write immediately, then on an interval. Idle = 'ok';
+    // turn_start/turn_end flip the status so `fleet ps` reflects real activity.
+    if (nativeHbEnabled()) {
+      hbModel = readModelId(ctx);
+      writeNativeHeartbeat('ok', hbModel);
+      hbTimer = setInterval(() => writeNativeHeartbeat(hbStatus, hbModel), HB_INTERVAL_MS);
+      if (typeof hbTimer.unref === 'function') hbTimer.unref();
+    }
   });
 
-  // ── Session End ───────────────────────────────────────────────────────
+  // ── Turn lifecycle → accurate busy/ok heartbeat ───────────────────────
-  pi.on('session_end', async (_event, _ctx) => {
+  pi.on('turn_start', async (_event, ctx) => {
+    hbStatus = 'busy';
+    hbModel = readModelId(ctx) ?? hbModel;
+    writeNativeHeartbeat('busy', hbModel);
+  });
+  pi.on('turn_end', async (_event, ctx) => {
+    hbStatus = 'ok';
+    hbModel = readModelId(ctx) ?? hbModel;
+    writeNativeHeartbeat('ok', hbModel);
+  });
+
+  // ── Session Shutdown ──────────────────────────────────────────────────
+  // (The pi API event is 'session_shutdown'; the prior 'session_end' handler
+  // never fired — fixed here so repo hooks + lock cleanup actually run.)
+  pi.on('session_shutdown', async (_event, _ctx) => {
+    if (hbTimer) {
+      clearInterval(hbTimer);
+      hbTimer = null;
+    }
+    clearNativeMarker();
+
     // Run repo session-end hook
     runRepoHook(sessionCwd, 'session-end');
 
@@ -252,4 +343,32 @@ export default function register(pi: ExtensionAPI) {
       }
     },
   });
+
+  // ── Register mosaic_mission_status tool (model-callable) ──────────────
+  // R14 "proper tool usage": give the agent a first-class tool to load its
+  // active Mosaic mission, milestone progress, task counts, and latest
+  // scratchpad — so it self-orients on in-flight work before planning,
+  // instead of shelling out or guessing. Mirrors the /mosaic-status command
+  // but returns the summary as tool output the LLM can read.
+  pi.registerTool({
+    name: 'mosaic_mission_status',
+    label: 'Mosaic Mission Status',
+    description:
+      'Return the active Mosaic mission, milestone progress, task counts, and latest scratchpad for the current project. Returns a note when no mission is active.',
+    promptSnippet: 'Read the active Mosaic mission + task state for the current project',
+    promptGuidelines: [
+      'Use mosaic_mission_status at the start of a session or task to load the active mission, milestone progress, and open tasks before planning work.',
+    ],
+    parameters: Type.Object({}),
+    async execute(_toolCallId, _params, _signal, _onUpdate, _ctx) {
+      const mission = detectMission(sessionCwd);
+      const text = mission
+        ? buildMissionSummary(sessionCwd, mission)
+        : 'No active Mosaic mission in this project.';
+      return {
+        content: [{ type: 'text', text }],
+        details: mission ? { ...mission } : { active: false },
+      };
+    },
+  });
 }

packages/mosaic/framework/tools/_scripts/mosaic-init

@@ -274,6 +274,13 @@ detect_existing_config
 echo "[mosaic-init] Generating SOUL.md — agent identity contract"
 echo ""
 
+# Fail-closed persona: in non-interactive mode the agent NAME must be supplied
+# explicitly (--name) — never silently ship an agent named "Assistant".
+if [[ $NON_INTERACTIVE -eq 1 && -z "$AGENT_NAME" ]]; then
+  echo "[mosaic-init] ERROR: --name (agent name) is required in non-interactive mode." >&2
+  exit 1
+fi
+
 prompt_if_empty AGENT_NAME "What name should agents use" "Assistant"
 prompt_if_empty ROLE_DESCRIPTION "Agent role description" "execution partner and visibility engine"
 

packages/mosaic/framework/tools/fleet/start-agent-session.sh

@@ -6,6 +6,8 @@ MOSAIC_TMUX_SOCKET=${MOSAIC_TMUX_SOCKET:-mosaic-factory}
 MOSAIC_AGENT_RUNTIME=${MOSAIC_AGENT_RUNTIME:-pi}
 MOSAIC_AGENT_WORKDIR=${MOSAIC_AGENT_WORKDIR:-$HOME}
 MOSAIC_AGENT_COMMAND=${MOSAIC_AGENT_COMMAND:-}
+MOSAIC_HEARTBEAT_RUN_DIR=${MOSAIC_HEARTBEAT_RUN_DIR:-${MOSAIC_HOME:-$HOME/.config/mosaic}/fleet/run}
+MOSAIC_HEARTBEAT_INTERVAL=${MOSAIC_HEARTBEAT_INTERVAL:-15}
 
 if [ -z "$AGENT_NAME" ]; then
   echo "ERROR: agent name argument or MOSAIC_AGENT_NAME is required" >&2
@@ -26,5 +28,132 @@ if [ -z "$MOSAIC_AGENT_COMMAND" ]; then
   MOSAIC_AGENT_COMMAND="mosaic yolo $MOSAIC_AGENT_RUNTIME"
 fi
 
+# ── Derive a runtime-bin PATH prefix ─────────────────────────────────────────
+# Precedence:
+#   1. $MOSAIC_RUNTIME_BIN (explicit override)
+#   2. $(npm config get prefix)/bin  (if npm is on PATH)
+#   3. Fallbacks: $HOME/.npm-global/bin and $HOME/.local/bin
+#
+# Only directories that already exist are included.  The prefix is baked into
+# the pane command regardless of what the LAUNCHER process's $PATH contains,
+# because the tmux pane inherits the tmux SERVER environment (not this script's
+# environment).  A dir on the launcher's PATH may be absent from the server PATH,
+# so every existing candidate must always be included.  Dedup within the
+# constructed prefix avoids listing the same dir twice.
+_build_runtime_bin_prefix() {
+  local candidates=()
+
+  if [ -n "${MOSAIC_RUNTIME_BIN:-}" ]; then
+    candidates+=("$MOSAIC_RUNTIME_BIN")
+  fi
+
+  if command -v npm >/dev/null 2>&1; then
+    local npm_prefix
+    npm_prefix=$(npm config get prefix 2>/dev/null) || true
+    if [ -n "$npm_prefix" ]; then
+      candidates+=("${npm_prefix}/bin")
+    fi
+  fi
+
+  candidates+=("$HOME/.npm-global/bin")
+  candidates+=("$HOME/.local/bin")
+
+  local prefix=""
+  for dir in "${candidates[@]}"; do
+    [ -d "$dir" ] || continue
+    if [ -z "$prefix" ]; then
+      prefix="$dir"
+    else
+      case ":${prefix}:" in
+        *":${dir}:"*) ;;  # already in our prefix — skip
+        *) prefix="${prefix}:${dir}" ;;
+      esac
+    fi
+  done
+
+  printf '%s' "$prefix"
+}
+
+MOSAIC_RUNTIME_BIN_PREFIX=$(_build_runtime_bin_prefix)
+
+# ── Build the pane command ────────────────────────────────────────────────────
+# The pane command must:
+#   - Export the augmented PATH so the runtime binary is found.
+#   - exec the agent command so the runtime is the pane's foreground process
+#     (makes `fleet ps` pane_current_command check reliable; no DRIFT false-positive).
+#
+# Quoting strategy: single-quote the inner shell snippet so that variable
+# references in MOSAIC_AGENT_COMMAND are NOT expanded here — they expand inside
+# the pane shell.  However, MOSAIC_RUNTIME_BIN_PREFIX and PATH must be expanded
+# NOW (in this script) because the pane shell inherits the tmux server
+# environment, not this script's env.
+#
+# We build the snippet as a double-quoted here-string embedded in a printf call
+# to avoid nested quoting problems.
+#
+# MOSAIC_AGENT_NAME must also be exported INTO the pane: panes inherit the tmux
+# server environment (not this script's, and not the systemd unit's), so the
+# name would otherwise be empty in-pane and the runtime's native heartbeat
+# (which gates on MOSAIC_AGENT_NAME) would never fire. %q-quote it so it is a
+# safe single bash token regardless of the name's characters.
+AGENT_NAME_Q=$(printf '%q' "$AGENT_NAME")
+
+if [ -n "$MOSAIC_RUNTIME_BIN_PREFIX" ]; then
+  PANE_SHELL_SNIPPET="export MOSAIC_AGENT_NAME=${AGENT_NAME_Q}; export PATH=\"${MOSAIC_RUNTIME_BIN_PREFIX}:\${PATH}\"; exec ${MOSAIC_AGENT_COMMAND}"
+else
+  PANE_SHELL_SNIPPET="export MOSAIC_AGENT_NAME=${AGENT_NAME_Q}; exec ${MOSAIC_AGENT_COMMAND}"
+fi
+
 mkdir -p "$MOSAIC_AGENT_WORKDIR"
-exec tmux -L "$MOSAIC_TMUX_SOCKET" new-session -d -s "$AGENT_NAME" -c "$MOSAIC_AGENT_WORKDIR" "$MOSAIC_AGENT_COMMAND"
+
+# ── Launch the tmux session (no exec — we continue to wire the heartbeat) ────
+tmux -L "$MOSAIC_TMUX_SOCKET" new-session -d -s "$AGENT_NAME" -c "$MOSAIC_AGENT_WORKDIR" \
+  bash -c "$PANE_SHELL_SNIPPET"
+
+# ── Resolve the pane PID (retry briefly to let the session initialise) ────────
+PANE_PID=""
+for _retry in 1 2 3 4 5; do
+  PANE_PID=$(tmux -L "$MOSAIC_TMUX_SOCKET" list-panes \
+    -t "=${AGENT_NAME}:0.0" -F '#{pane_pid}' 2>/dev/null || true)
+  [ -n "$PANE_PID" ] && break
+  sleep 0.2
+done
+
+# ── Spawn the heartbeat sidecar (detached, best-effort) ──────────────────────
+# The sidecar writes ~/.config/mosaic/fleet/run/<AGENT>.hb atomically while the
+# pane process is alive, then exits so the file goes stale (fleet ps shows stale
+# then PANE=dead).  It is runtime-agnostic: it only cares about the pane PID.
+_start_heartbeat_sidecar() {
+  local agent="$1"
+  local pane_pid="$2"
+  local run_dir="$3"
+  local interval="$4"
+  local hb_file="${run_dir}/${agent}.hb"
+
+  mkdir -p "$run_dir"
+
+  # Write the sidecar as a self-contained bash one-liner so it carries no
+  # references to any variables from this script's environment.
+  local sidecar_script
+  sidecar_script=$(printf \
+    'hb=%q; pid=%q; iv=%q; mkdir -p "$(dirname "$hb")"; while kill -0 "$pid" 2>/dev/null; do nat="$hb.native"; if [ -f "$nat" ] && [ "$(( $(date +%%s) - $(stat -c %%Y "$nat" 2>/dev/null || echo 0) ))" -lt "$(( iv * 2 ))" ]; then sleep "$iv"; continue; fi; tmp="$hb.tmp.$$"; printf "ts=%%s\npid=%%s\nstatus=ok\n" "$(date +%%Y-%%m-%%dT%%H:%%M:%%S%%z)" "$pid" > "$tmp" && mv "$tmp" "$hb"; sleep "$iv"; done' \
+    "$hb_file" "$pane_pid" "$interval")
+
+  # setsid + disown ensures the sidecar survives this script exiting.
+  # stderr/stdout go to /dev/null; failures are non-fatal.
+  if command -v setsid >/dev/null 2>&1; then
+    setsid bash -c "$sidecar_script" </dev/null >/dev/null 2>&1 &
+  else
+    bash -c "$sidecar_script" </dev/null >/dev/null 2>&1 &
+  fi
+  disown $! 2>/dev/null || true
+}
+
+if [ -n "$PANE_PID" ]; then
+  # Guard: do not let sidecar startup failures abort the launcher (set -e).
+  _start_heartbeat_sidecar "$AGENT_NAME" "$PANE_PID" \
+    "$MOSAIC_HEARTBEAT_RUN_DIR" "$MOSAIC_HEARTBEAT_INTERVAL" || \
+    echo "WARNING: heartbeat sidecar could not be started for $AGENT_NAME" >&2
+else
+  echo "WARNING: could not resolve pane PID for $AGENT_NAME — heartbeat sidecar not started" >&2
+fi

packages/mosaic/framework/tools/fleet/test-start-agent-session.sh

@@ -6,22 +6,43 @@ START="$SCRIPT_DIR/start-agent-session.sh"
 SOCKET="mosaic-agent-test-$RANDOM-$$"
 AGENT="agent-$RANDOM"
 WORKDIR=$(mktemp -d)
-trap 'tmux -L "$SOCKET" kill-server >/dev/null 2>&1 || true; rm -rf "$WORKDIR"' EXIT
+
+# Keep a single cleanup trap that accumulates resources.
+CLEANUP_DIRS=("$WORKDIR")
+CLEANUP_SOCKETS=("$SOCKET")
+trap '_cleanup' EXIT
+_cleanup() {
+  for s in "${CLEANUP_SOCKETS[@]:-}"; do
+    tmux -L "$s" kill-server >/dev/null 2>&1 || true
+  done
+  for d in "${CLEANUP_DIRS[@]:-}"; do
+    rm -rf "$d"
+  done
+}
 
 fail() {
   echo "FAIL: $*" >&2
   exit 1
 }
 
+# ── Test 1: basic session creation with workdir check ─────────────────────────
 MOSAIC_TMUX_SOCKET="$SOCKET" \
 MOSAIC_AGENT_WORKDIR="$WORKDIR" \
 MOSAIC_AGENT_COMMAND='bash --noprofile --norc -i' \
   "$START" "$AGENT"
 
 tmux -L "$SOCKET" has-session -t "=$AGENT:0.0" || fail "agent session was not created"
-actual_dir=$(tmux -L "$SOCKET" display-message -p -t "=$AGENT:0.0" '#{pane_current_path}')
+# Retry: pane_current_path briefly reflects the tmux server's cwd until the pane
-[ "$actual_dir" = "$WORKDIR" ] || fail "agent workdir mismatch: $actual_dir"
+# process establishes its own cwd (the -c start dir). Poll until it settles.
+actual_dir=""
+for _ in $(seq 1 30); do
+  actual_dir=$(tmux -L "$SOCKET" display-message -p -t "=$AGENT:0.0" '#{pane_current_path}')
+  [ "$actual_dir" = "$WORKDIR" ] && break
+  sleep 0.1
+done
+[ "$actual_dir" = "$WORKDIR" ] || fail "agent workdir mismatch: $actual_dir (expected $WORKDIR)"
 
+# ── Test 2: idempotency (duplicate start prints 'already running') ─────────────
 MOSAIC_TMUX_SOCKET="$SOCKET" \
 MOSAIC_AGENT_WORKDIR="$WORKDIR" \
 MOSAIC_AGENT_COMMAND='bash --noprofile --norc -i' \
@@ -29,4 +50,310 @@ MOSAIC_AGENT_COMMAND='bash --noprofile --norc -i' \
 
 grep -qF 'already running' /tmp/mosaic-start-agent-idempotent.out || fail "duplicate start was not idempotent"
 
+# ── Test 3: runtime-bin PATH prefix is baked into the pane command ────────────
+#
+# We capture the command the script would hand to tmux by injecting a fake
+# 'tmux' shim into PATH.  The shim:
+#   - Intercepts 'new-session' calls and records its arguments to a file.
+#   - For 'has-session' calls, exits 1 (session does not exist) so the script
+#     proceeds to launch instead of printing "already running".
+#   - For 'list-panes' calls, returns empty so PANE_PID stays unset and the
+#     heartbeat sidecar is NOT spawned (heartbeat is not the focus of this test;
+#     test 6 and 7 cover that path).  This prevents any real-filesystem side
+#     effects or leaked background processes.
+#   - For all other subcommands, exits 0.
+#
+# Assertions:
+#   a) 'export PATH=' with the synthetic MOSAIC_RUNTIME_BIN prefix appears.
+#   b) 'exec' appears so the runtime replaces the wrapper shell.
+#   c) MOSAIC_AGENT_COMMAND with flags is forwarded intact.
+
+FAKE_BIN=$(mktemp -d)
+FAKE_RUNTIME_BIN=$(mktemp -d)
+TMUX_ARGS_FILE=$(mktemp)
+HB_RUN_DIR3=$(mktemp -d)
+CLEANUP_DIRS+=("$FAKE_BIN" "$FAKE_RUNTIME_BIN" "$HB_RUN_DIR3")
+
+# Write the fake tmux shim (uses only positional args, no sourced vars).
+cat > "$FAKE_BIN/tmux" <<SHIM
+#!/usr/bin/env bash
+# Fake tmux: record new-session args; report has-session as missing.
+subcmd="\$3"  # argv: tmux -L <socket> <subcmd> ...
+if [ "\$subcmd" = "has-session" ]; then
+  exit 1   # session not found → script will attempt new-session
+fi
+if [ "\$subcmd" = "new-session" ]; then
+  printf '%s\n' "\$@" > "$TMUX_ARGS_FILE"
+  exit 0
+fi
+if [ "\$subcmd" = "list-panes" ]; then
+  # Return empty: no sidecar spawned (heartbeat is not the focus of this test).
+  echo ""
+  exit 0
+fi
+exit 0
+SHIM
+chmod +x "$FAKE_BIN/tmux"
+
+SOCKET3="mosaic-agent-test3-$RANDOM-$$"
+AGENT3="agent3-$RANDOM"
+WORKDIR3=$(mktemp -d)
+CLEANUP_DIRS+=("$WORKDIR3")
+
+PATH="$FAKE_BIN:$PATH" \
+MOSAIC_TMUX_SOCKET="$SOCKET3" \
+MOSAIC_AGENT_WORKDIR="$WORKDIR3" \
+MOSAIC_AGENT_RUNTIME="pi" \
+MOSAIC_RUNTIME_BIN="$FAKE_RUNTIME_BIN" \
+MOSAIC_AGENT_COMMAND="mosaic yolo pi --model openai-codex/gpt-5.5:high" \
+MOSAIC_HEARTBEAT_RUN_DIR="$HB_RUN_DIR3" \
+  "$START" "$AGENT3"
+
+all_args=$(cat "$TMUX_ARGS_FILE" 2>/dev/null || true)
+rm -f "$TMUX_ARGS_FILE"
+
+echo "--- captured tmux new-session args ---"
+echo "$all_args"
+echo "--- end args ---"
+
+# a) PATH prefix containing FAKE_RUNTIME_BIN must appear.
+echo "$all_args" | grep -qF "export PATH=" || fail "pane command does not export PATH"
+echo "$all_args" | grep -qF "$FAKE_RUNTIME_BIN" || fail "pane command does not include MOSAIC_RUNTIME_BIN in PATH prefix"
+
+# b) exec must appear so the runtime replaces the wrapper shell.
+echo "$all_args" | grep -qF "exec " || fail "pane command does not use exec"
+
+# c) Full MOSAIC_AGENT_COMMAND (with flags) must be forwarded.
+echo "$all_args" | grep -qF "mosaic yolo pi --model openai-codex/gpt-5.5:high" || \
+  fail "pane command does not forward MOSAIC_AGENT_COMMAND with flags intact"
+
+# ── Test 4: when no extra runtime-bin dirs exist, exec still appears ───────────
+TMUX_ARGS_FILE2=$(mktemp)
+FAKE_BIN2=$(mktemp -d)
+HB_RUN_DIR4=$(mktemp -d)
+CLEANUP_DIRS+=("$FAKE_BIN2" "$HB_RUN_DIR4")
+
+cat > "$FAKE_BIN2/tmux" <<SHIM2
+#!/usr/bin/env bash
+subcmd="\$3"
+if [ "\$subcmd" = "has-session" ]; then exit 1; fi
+if [ "\$subcmd" = "new-session" ]; then
+  printf '%s\n' "\$@" > "$TMUX_ARGS_FILE2"
+  exit 0
+fi
+if [ "\$subcmd" = "list-panes" ]; then
+  # Return empty: no sidecar spawned (heartbeat is not the focus of this test).
+  echo ""
+  exit 0
+fi
+exit 0
+SHIM2
+chmod +x "$FAKE_BIN2/tmux"
+
+SOCKET4="mosaic-agent-test4-$RANDOM-$$"
+AGENT4="agent4-$RANDOM"
+WORKDIR4=$(mktemp -d)
+CLEANUP_DIRS+=("$WORKDIR4")
+
+# MOSAIC_RUNTIME_BIN points to a non-existent dir so prefix will be empty;
+# .npm-global/bin and .local/bin may or may not exist but we just want exec.
+PATH="$FAKE_BIN2:$PATH" \
+MOSAIC_TMUX_SOCKET="$SOCKET4" \
+MOSAIC_AGENT_WORKDIR="$WORKDIR4" \
+MOSAIC_AGENT_RUNTIME="pi" \
+MOSAIC_RUNTIME_BIN="/nonexistent-dir-$$" \
+MOSAIC_AGENT_COMMAND="mosaic yolo pi" \
+MOSAIC_HEARTBEAT_RUN_DIR="$HB_RUN_DIR4" \
+  "$START" "$AGENT4"
+
+all_args4=$(cat "$TMUX_ARGS_FILE2" 2>/dev/null || true)
+rm -f "$TMUX_ARGS_FILE2"
+rm -rf "$WORKDIR4"
+
+echo "$all_args4" | grep -qF "exec " || fail "pane command (no prefix dirs) does not use exec"
+echo "$all_args4" | grep -qF "mosaic yolo pi" || fail "pane command does not include agent command when no prefix"
+
+# ── Test 5: candidate dir already in LAUNCHER $PATH is still baked into pane ──
+#
+# Regression guard for the bug where _build_runtime_bin_prefix() used to skip
+# a candidate because it was already present in the launcher process's $PATH.
+# That check was wrong: the pane inherits the tmux SERVER environment, not the
+# launcher's env.  Even if a dir is on the launcher's PATH it must always be
+# baked into the pane's PATH export.
+#
+# We prove this by setting PATH to include FAKE_RUNTIME_BIN5 (the candidate),
+# then asserting the generated new-session command still exports it.
+TMUX_ARGS_FILE5=$(mktemp)
+FAKE_BIN5=$(mktemp -d)
+FAKE_RUNTIME_BIN5=$(mktemp -d)  # this dir IS on the launcher's PATH below
+HB_RUN_DIR5=$(mktemp -d)
+CLEANUP_DIRS+=("$FAKE_BIN5" "$FAKE_RUNTIME_BIN5" "$HB_RUN_DIR5")
+
+cat > "$FAKE_BIN5/tmux" <<SHIM5
+#!/usr/bin/env bash
+subcmd="\$3"
+if [ "\$subcmd" = "has-session" ]; then exit 1; fi
+if [ "\$subcmd" = "new-session" ]; then
+  printf '%s\n' "\$@" > "$TMUX_ARGS_FILE5"
+  exit 0
+fi
+if [ "\$subcmd" = "list-panes" ]; then
+  # Return empty: no sidecar spawned (heartbeat is not the focus of this test).
+  echo ""
+  exit 0
+fi
+exit 0
+SHIM5
+chmod +x "$FAKE_BIN5/tmux"
+
+SOCKET5="mosaic-agent-test5-$RANDOM-$$"
+AGENT5="agent5-$RANDOM"
+WORKDIR5=$(mktemp -d)
+CLEANUP_DIRS+=("$WORKDIR5")
+CLEANUP_SOCKETS+=("$SOCKET5")
+
+# FAKE_RUNTIME_BIN5 is deliberately placed on the LAUNCHER PATH so that the
+# old (buggy) code would have skipped it.  The correct code must still include
+# it in the pane PATH export.
+PATH="$FAKE_BIN5:$FAKE_RUNTIME_BIN5:$PATH" \
+MOSAIC_TMUX_SOCKET="$SOCKET5" \
+MOSAIC_AGENT_WORKDIR="$WORKDIR5" \
+MOSAIC_AGENT_RUNTIME="pi" \
+MOSAIC_RUNTIME_BIN="$FAKE_RUNTIME_BIN5" \
+MOSAIC_AGENT_COMMAND="mosaic yolo pi" \
+MOSAIC_HEARTBEAT_RUN_DIR="$HB_RUN_DIR5" \
+  "$START" "$AGENT5"
+
+all_args5=$(cat "$TMUX_ARGS_FILE5" 2>/dev/null || true)
+rm -f "$TMUX_ARGS_FILE5"
+rm -rf "$WORKDIR5"
+
+echo "--- test 5: launcher-PATH candidate must still appear in pane export ---"
+echo "$all_args5"
+echo "--- end test 5 args ---"
+
+echo "$all_args5" | grep -qF "export PATH=" || \
+  fail "test5: pane command does not export PATH when candidate is on launcher PATH"
+echo "$all_args5" | grep -qF "$FAKE_RUNTIME_BIN5" || \
+  fail "test5: candidate dir (already on launcher PATH) was NOT baked into pane PATH — regression"
+
+# ── Test 6: heartbeat sidecar — pane PID resolved + .hb file written ──────────
+#
+# Uses a real tmux session (same socket as test 1 which already has $AGENT) so
+# list-panes returns a real pane PID.  We override MOSAIC_HEARTBEAT_RUN_DIR to
+# a temp dir and set a 1-second interval, then wait up to 3 s for the .hb file
+# to appear and check its content.
+
+HB_RUN_DIR=$(mktemp -d)
+CLEANUP_DIRS+=("$HB_RUN_DIR")
+
+# Re-use the session+agent created in Test 1 (still alive on $SOCKET / $AGENT).
+# We need to invoke the script for a NEW agent on the same socket to exercise
+# the heartbeat path with a real pane PID.
+AGENT6="agent6-$RANDOM"
+MOSAIC_TMUX_SOCKET="$SOCKET" \
+MOSAIC_AGENT_WORKDIR="$WORKDIR" \
+MOSAIC_AGENT_COMMAND='bash --noprofile --norc -i' \
+MOSAIC_HEARTBEAT_RUN_DIR="$HB_RUN_DIR" \
+MOSAIC_HEARTBEAT_INTERVAL="1" \
+  "$START" "$AGENT6"
+
+HB_FILE="$HB_RUN_DIR/${AGENT6}.hb"
+
+# Wait up to 5 seconds for the heartbeat file to appear.
+_waited=0
+until [ -f "$HB_FILE" ] || [ "$_waited" -ge 5 ]; do
+  sleep 0.5
+  _waited=$((_waited + 1))
+done
+
+[ -f "$HB_FILE" ] || fail "test6: heartbeat file not written at $HB_FILE within 5s"
+
+hb_content=$(cat "$HB_FILE")
+echo "--- test 6: heartbeat file content ---"
+echo "$hb_content"
+echo "--- end test 6 ---"
+
+# Verify required fields are present.
+echo "$hb_content" | grep -qE '^ts=[0-9]{4}-[0-9]{2}-[0-9]{2}T' || \
+  fail "test6: heartbeat ts field missing or malformed"
+echo "$hb_content" | grep -qE '^pid=[0-9]+' || \
+  fail "test6: heartbeat pid field missing or malformed"
+echo "$hb_content" | grep -qF 'status=ok' || \
+  fail "test6: heartbeat status=ok missing"
+
+# ── Test 7: heartbeat sidecar — targets correct .hb path per agent name ────────
+#
+# Uses the fake-tmux shim approach (like tests 3-5) to capture the sidecar
+# invocation without needing a real session.  A fake setsid shim records its
+# arguments so we can assert the sidecar script targets the expected .hb path
+# and uses the configured interval.
+
+FAKE_BIN7=$(mktemp -d)
+FAKE_RUNTIME_BIN7=$(mktemp -d)
+SETSID_ARGS_FILE=$(mktemp)
+HB_RUN_DIR7=$(mktemp -d)
+CLEANUP_DIRS+=("$FAKE_BIN7" "$FAKE_RUNTIME_BIN7" "$HB_RUN_DIR7")
+
+AGENT7="my-fleet-agent-$RANDOM"
+INTERVAL7="42"
+
+# Fake tmux: has-session → not found; new-session → ok; list-panes → known PID.
+cat > "$FAKE_BIN7/tmux" <<SHIM7
+#!/usr/bin/env bash
+subcmd="\$3"
+if [ "\$subcmd" = "has-session" ]; then exit 1; fi
+if [ "\$subcmd" = "new-session" ]; then exit 0; fi
+if [ "\$subcmd" = "list-panes" ]; then echo "88888"; exit 0; fi
+exit 0
+SHIM7
+chmod +x "$FAKE_BIN7/tmux"
+
+# Fake setsid: capture the bash -c <script> argument for inspection, then
+# background an actual bash subshell so disown succeeds in the caller.
+cat > "$FAKE_BIN7/setsid" <<'SETSID_SHIM'
+#!/usr/bin/env bash
+# argv: setsid bash -c <sidecar_script>
+# Record the full argument list to the capture file, then exit cleanly.
+printf '%s\0' "$@" > __SETSID_ARGS_FILE__
+exit 0
+SETSID_SHIM
+# Patch the placeholder with the real capture-file path (avoids heredoc expansion issues).
+sed -i "s|__SETSID_ARGS_FILE__|${SETSID_ARGS_FILE}|g" "$FAKE_BIN7/setsid"
+chmod +x "$FAKE_BIN7/setsid"
+
+SOCKET7="mosaic-agent-test7-$RANDOM-$$"
+WORKDIR7=$(mktemp -d)
+CLEANUP_DIRS+=("$WORKDIR7")
+
+PATH="$FAKE_BIN7:$PATH" \
+MOSAIC_TMUX_SOCKET="$SOCKET7" \
+MOSAIC_AGENT_WORKDIR="$WORKDIR7" \
+MOSAIC_AGENT_RUNTIME="pi" \
+MOSAIC_RUNTIME_BIN="$FAKE_RUNTIME_BIN7" \
+MOSAIC_AGENT_COMMAND="mosaic yolo pi" \
+MOSAIC_HEARTBEAT_RUN_DIR="$HB_RUN_DIR7" \
+MOSAIC_HEARTBEAT_INTERVAL="$INTERVAL7" \
+  "$START" "$AGENT7"
+
+# Give the background setsid shim a moment to finish writing the capture file.
+sleep 0.5
+
+setsid_args=$(cat "$SETSID_ARGS_FILE" 2>/dev/null | tr '\0' '\n' || true)
+rm -f "$SETSID_ARGS_FILE"
+rm -rf "$WORKDIR7"
+
+echo "--- test 7: captured setsid args ---"
+echo "$setsid_args"
+echo "--- end test 7 ---"
+
+# The sidecar script (bash -c <script>) must reference the correct .hb path.
+expected_hb="${HB_RUN_DIR7}/${AGENT7}.hb"
+echo "$setsid_args" | grep -qF "$expected_hb" || \
+  fail "test7: sidecar script does not reference correct .hb path ($expected_hb)"
+
+# The sidecar script must use the configured interval.
+echo "$setsid_args" | grep -qF "$INTERVAL7" || \
+  fail "test7: sidecar script does not reference configured interval ($INTERVAL7)"
+
 echo "ok - start-agent-session"

packages/mosaic/framework/tools/quality/scripts/check-resident-budget.sh

@@ -0,0 +1,93 @@
+#!/usr/bin/env bash
+# check-resident-budget.sh — resident line-count ceiling (R9 / DESIGN §7).
+#
+# Budgets the *container* (line count) of the framework-owned files that are
+# injected into every agent's context by value — the Constitution (L0), the
+# AGENTS dispatcher, and each runtime RUNTIME.md slice. Gate *wording* is never
+# capped (a word cap forces paraphrasing law — the exact drift vector P3 killed);
+# only the file's line count is bounded, so prose creep is caught in review.
+#
+# This is the CI-enforceable half of the budget. The per-harness *total* resident
+# prompt (which also includes user-generated SOUL.md/USER.md and the per-tier
+# slice) is summed by `mosaic doctor` as a runtime advisory — CI cannot see user
+# files, so it is deliberately out of scope here (DESIGN §7).
+#
+# Usage:  check-resident-budget.sh [--self-test]
+# Exit:   0 = all within budget · 1 = a file exceeds its ceiling · 2 = self-test failed
+set -uo pipefail
+
+FW="$(cd "$(dirname "${BASH_SOURCE[0]}")/../../.." && pwd)" # packages/mosaic/framework
+
+# Per-file ceilings (lines). Headroom above current counts; tighten as files settle.
+# Format: "<relative-path>:<max-lines>"
+CEILINGS=(
+  "defaults/CONSTITUTION.md:120"
+  "defaults/AGENTS.md:120"
+  "runtime/claude/RUNTIME.md:90"
+  "runtime/codex/RUNTIME.md:90"
+  "runtime/opencode/RUNTIME.md:90"
+  "runtime/pi/RUNTIME.md:90"
+)
+
+# check_file <abs-path> <max> → echoes "<n>"; returns 0 if n<=max, 1 otherwise.
+check_file() {
+  local path="$1" max="$2" n
+  n=$(wc -l <"$path" 2>/dev/null || echo 0)
+  n=$((n + 0))
+  echo "$n"
+  [ "$n" -le "$max" ]
+}
+
+run_budget() {
+  local fail=0 rel max abs n
+  printf '%-32s %8s %8s   %s\n' "FILE" "LINES" "CEILING" "STATUS"
+  for entry in "${CEILINGS[@]}"; do
+    rel="${entry%%:*}"
+    max="${entry##*:}"
+    abs="$FW/$rel"
+    if [ ! -f "$abs" ]; then
+      printf '%-32s %8s %8s   %s\n' "$rel" "-" "$max" "MISSING"
+      fail=1
+      continue
+    fi
+    n=$(check_file "$abs" "$max")
+    if [ "$n" -le "$max" ]; then
+      printf '%-32s %8s %8s   %s\n' "$rel" "$n" "$max" "ok"
+    else
+      printf '%-32s %8s %8s   %s\n' "$rel" "$n" "$max" "OVER BUDGET"
+      fail=1
+    fi
+  done
+  return "$fail"
+}
+
+self_test() {
+  local tmp rc
+  tmp=$(mktemp)
+  # 3 lines, ceiling 5 → within budget (rc 0)
+  printf 'a\nb\nc\n' >"$tmp"
+  check_file "$tmp" 5 >/dev/null
+  rc=$?
+  if [ "$rc" -ne 0 ]; then echo "self-test FAIL: under-budget file flagged"; rm -f "$tmp"; return 2; fi
+  # 6 lines, ceiling 5 → over budget (rc 1)
+  printf 'a\nb\nc\nd\ne\nf\n' >"$tmp"
+  check_file "$tmp" 5 >/dev/null
+  rc=$?
+  if [ "$rc" -ne 1 ]; then echo "self-test FAIL: over-budget file not flagged"; rm -f "$tmp"; return 2; fi
+  rm -f "$tmp"
+  echo "self-test OK"
+  return 0
+}
+
+if [ "${1:-}" = "--self-test" ]; then
+  self_test
+  exit $?
+fi
+
+if run_budget; then
+  echo "Resident budget: all framework-owned resident files within ceiling."
+  exit 0
+else
+  echo "Resident budget EXCEEDED — trim prose or raise the ceiling deliberately (see DESIGN §7)." >&2
+  exit 1
+fi

packages/mosaic/framework/tools/quality/scripts/test-install-migration.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+# test-install-migration.sh — fixture matrix for the v2→v3 (Constitution) upgrade
+# migration in install.sh. Runs the installer against throwaway MOSAIC_HOME dirs
+# with MOSAIC_SYNC_ONLY=1 (file phase only — no environment-touching post-install)
+# and asserts the framework-owned-overwrite + user-preserve + backup semantics.
+#
+# Mirrors the TS fixture suite in packages/mosaic/src/config/file-adapter.test.ts;
+# both installers MUST behave identically.
+#
+# Usage:  bash test-install-migration.sh
+set -uo pipefail
+
+FW="$(cd "$(dirname "${BASH_SOURCE[0]}")/../../.." && pwd)"   # packages/mosaic/framework
+INSTALL="$FW/install.sh"
+DEFA="$FW/defaults"
+
+pass=0; fail=0
+chk() { if eval "$2"; then echo "  ✓ $1"; pass=$((pass + 1)); else echo "  ✗ $1"; fail=$((fail + 1)); fi; }
+run() { MOSAIC_HOME="$1" MOSAIC_INSTALL_MODE="$2" MOSAIC_SYNC_ONLY=1 bash "$INSTALL" >/dev/null 2>&1; }
+
+echo "install.sh v2→v3 migration fixture matrix:"
+
+# F1 — fresh install
+T1=$(mktemp -d); run "$T1" overwrite
+chk "F1 fresh: CONSTITUTION/AGENTS/STANDARDS/TOOLS seeded" \
+  "[ -f '$T1/CONSTITUTION.md' ] && [ -f '$T1/AGENTS.md' ] && [ -f '$T1/STANDARDS.md' ] && [ -f '$T1/TOOLS.md' ]"
+chk "F1 fresh: AGENTS == shipped default" "cmp -s '$T1/AGENTS.md' '$DEFA/AGENTS.md'"
+chk "F1 fresh: framework-version stamped 3" "[ \"\$(cat '$T1/.framework-version' 2>/dev/null)\" = 3 ]"
+
+# F2 — legacy install with a user-edited AGENTS.md (the sanctioned pre-constitution customization)
+T2=$(mktemp -d); mkdir -p "$T2/credentials"
+printf '# user-edited AGENTS pre-constitution\n' > "$T2/AGENTS.md"
+printf '# my persona\n' > "$T2/SOUL.md"
+printf 'token\n' > "$T2/credentials/c.json"
+echo 2 > "$T2/.framework-version"
+run "$T2" keep
+chk "F2 legacy-edited: AGENTS overwritten to framework version" "cmp -s '$T2/AGENTS.md' '$DEFA/AGENTS.md'"
+chk "F2 legacy-edited: prior AGENTS saved to .pre-constitution.bak" \
+  "grep -q 'user-edited AGENTS pre-constitution' '$T2/AGENTS.md.pre-constitution.bak'"
+chk "F2 legacy-edited: SOUL.md preserved" "grep -q 'my persona' '$T2/SOUL.md'"
+chk "F2 legacy-edited: credentials preserved" "grep -q token '$T2/credentials/c.json'"
+chk "F2 legacy-edited: CONSTITUTION.md installed" "[ -f '$T2/CONSTITUTION.md' ]"
+run "$T2" keep
+chk "F2 idempotent: .pre-constitution.bak preserved across a 2nd upgrade" \
+  "grep -q 'user-edited AGENTS pre-constitution' '$T2/AGENTS.md.pre-constitution.bak'"
+
+# F3 — user-tuned STANDARDS.md
+T3=$(mktemp -d); printf '# tuned standards\n' > "$T3/STANDARDS.md"; printf '# persona\n' > "$T3/SOUL.md"; echo 2 > "$T3/.framework-version"
+run "$T3" keep
+chk "F3 tuned-standard: STANDARDS overwritten" "cmp -s '$T3/STANDARDS.md' '$DEFA/STANDARDS.md'"
+chk "F3 tuned-standard: tuned copy backed up" "grep -q 'tuned standards' '$T3/STANDARDS.md.pre-constitution.bak'"
+
+# F4 — unattended / no TTY (stdin closed): must complete without hanging, default to keep
+T4=$(mktemp -d); printf '# persona\n' > "$T4/SOUL.md"; printf '# old\n' > "$T4/AGENTS.md"; echo 2 > "$T4/.framework-version"
+MOSAIC_HOME="$T4" MOSAIC_SYNC_ONLY=1 bash "$INSTALL" </dev/null >/dev/null 2>&1
+chk "F4 no-TTY: completed, AGENTS updated" "cmp -s '$T4/AGENTS.md' '$DEFA/AGENTS.md'"
+
+# F5 — failure path must not corrupt existing data (invalid mode rejected before any file op)
+T5=$(mktemp -d); mkdir -p "$T5/credentials"; printf '# orig\n' > "$T5/SOUL.md"; printf 'keepme\n' > "$T5/credentials/c.json"; echo 2 > "$T5/.framework-version"
+MOSAIC_HOME="$T5" MOSAIC_INSTALL_MODE=bogus MOSAIC_SYNC_ONLY=1 bash "$INSTALL" >/dev/null 2>&1; rc=$?
+chk "F5 failure: invalid mode rejected (nonzero exit)" "[ $rc -ne 0 ]"
+chk "F5 failure: SOUL + credentials intact" "grep -q orig '$T5/SOUL.md' && grep -q keepme '$T5/credentials/c.json'"
+
+rm -rf "$T1" "$T2" "$T3" "$T4" "$T5"
+echo
+echo "RESULT: $pass passed, $fail failed"
+[ "$fail" -eq 0 ]

packages/mosaic/framework/tools/quality/scripts/verify-sanitized.sh

@@ -12,7 +12,7 @@
 #   2. STRUCTURAL (private $HOME default in *.sh) — scanned everywhere EXCEPT examples/,
 #        because worked example overlays/personas legitimately show placeholder paths.
 #
-# File types: *.md, *.sh, *.ps1, *.json, and the extensionless CLI scripts under
+# File types: *.md, *.sh, *.ps1, *.json, *.yml/*.yaml, *.toml, *.env, *.service, and the CLI scripts under
 # tools/_scripts/. Excludes node_modules/ and this gate file.
 #
 # NOTE: '\bPDA\b' intentionally matches "PDA-friendly" (the contamination removed in P2);
@@ -39,7 +39,7 @@ cd "$FRAMEWORK_ROOT" || { echo "FRAMEWORK_ROOT not found: $FRAMEWORK_ROOT" >&2;
 # Identity scope = ALL shipped text files (examples/ INCLUDED).
 _files_identity() {
   find . -type f \
-    \( -name '*.md' -o -name '*.sh' -o -name '*.ps1' -o -name '*.json' -o -path '*/tools/_scripts/*' \) \
+    \( -name '*.md' -o -name '*.sh' -o -name '*.ps1' -o -name '*.json' -o -name '*.yml' -o -name '*.yaml' -o -name '*.toml' -o -name '*.env' -o -name '*.service' -o -path '*/tools/_scripts/*' \) \
     -not -path '*/node_modules/*' -not -path "./$SELF_REL" -print0
 }
 # Structural scope = shipped scripts, examples/ EXCLUDED.
@@ -53,9 +53,15 @@ _selftest() {
   local tmp; tmp="$(mktemp -d)" || return 1
   printf 'contact jason.woltje at jarvis-brain (PDA-friendly)\n' > "$tmp/planted.md"
   printf 'X="${VAR:-$HOME/src/whatever/x.json}"\n' > "$tmp/planted.sh"
+  printf 'name: jason-woltje\n' > "$tmp/planted.yaml"
+  printf '[Service]\nUser=jarvis\n' > "$tmp/planted.service"
   local rc=0
   grep -qIEi "$DENYLIST" "$tmp/planted.md" || { echo "✗ SELF-TEST: identity denylist regex broken" >&2; rc=1; }
   grep -qIE  "$STRUCTURAL_SH" "$tmp/planted.sh" || { echo "✗ SELF-TEST: structural regex broken" >&2; rc=1; }
+  # Prove the identity scan covers the config formats it claims to (yaml/service/etc).
+  local n_ext
+  n_ext=$(find "$tmp" -type f \( -name '*.yaml' -o -name '*.service' \) -print0 | xargs -0 -r grep -lIEi "$DENYLIST" 2>/dev/null | wc -l)
+  [[ "$n_ext" -eq 2 ]] || { echo "✗ SELF-TEST: identity scan does not cover .yaml/.service extensions" >&2; rc=1; }
   rm -rf "$tmp"; return $rc
 }
 _selftest || exit 2

packages/mosaic/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@mosaicstack/mosaic",
-  "version": "0.0.34",
+  "version": "0.0.39",
   "repository": {
     "type": "git",
     "url": "https://git.mosaicstack.dev/mosaicstack/stack.git",

packages/mosaic/src/cli.ts

@@ -26,6 +26,10 @@ import {
   checkForAllUpdates,
   formatAllPackagesTable,
   getInstallAllCommand,
+  runFrameworkReseed,
+  readRosterAgentNames,
+  buildRelaunchCommands,
+  FRAMEWORK_RESEED_PACKAGE,
 } from './runtime/update-checker.js';
 import { runWizard } from './wizard.js';
 import { ClackPrompter } from './prompter/clack-prompter.js';
@@ -404,7 +408,12 @@ program
   .command('update')
   .description('Check for and install Mosaic CLI updates')
   .option('--check', 'Check only, do not install')
-  .action(async (opts: { check?: boolean }) => {
+  .option(
+    '--no-reseed',
+    'Skip re-seeding framework files into ~/.config/mosaic after the CLI update',
+  )
+  .option('--relaunch', 'Restart durable fleet agents so the new launcher/runtime takes effect')
+  .action(async (opts: { check?: boolean; reseed?: boolean; relaunch?: boolean }) => {
     // checkForAllUpdates imported statically above
     const { execSync } = await import('node:child_process');
 
@@ -442,6 +451,51 @@ program
       console.error('\nUpdate failed. Try manually: bash tools/install.sh');
       process.exit(1);
     }
+
+    // F3-m3 / R13: the CLI is updated, but the framework files in
+    // ~/.config/mosaic/ are still the previous version. Re-seed them from the
+    // freshly-installed package so shipped launcher/runtime changes ACTIVATE.
+    // Only when the framework-bearing package itself updated.
+    const mosaicUpdated = outdated.some(
+      (r: { package: string }) => r.package === FRAMEWORK_RESEED_PACKAGE,
+    );
+    if (mosaicUpdated && opts.reseed !== false) {
+      console.log(
+        '\nRe-seeding framework files into ~/.config/mosaic (data-safe; keeps your edits)…',
+      );
+      const reseed = runFrameworkReseed();
+      if (reseed.ok) {
+        console.log('✔ Framework re-seeded.');
+        const agents = readRosterAgentNames();
+        if (agents.length > 0) {
+          if (opts.relaunch) {
+            console.log(
+              `\nRelaunching ${agents.length} fleet agent(s) to pick up the new runtime…`,
+            );
+            for (const restart of buildRelaunchCommands(agents)) {
+              try {
+                execSync(restart.join(' '), { stdio: 'inherit', timeout: 30_000 });
+              } catch {
+                console.error(`  ⚠ failed to restart agent — run: ${restart.join(' ')}`);
+              }
+            }
+            console.log('✔ Agents relaunched.');
+          } else {
+            console.log(
+              `\nℹ ${agents.length} fleet agent(s) are still running the previous runtime. ` +
+                'Restart them to activate the update:\n    mosaic update --relaunch   ' +
+                '(or: mosaic fleet restart <agent>)',
+            );
+          }
+        }
+      } else {
+        console.error(
+          `\n⚠ Framework re-seed skipped: ${reseed.reason ?? 'unknown'}.\n` +
+            '  Activate manually: bash "$(npm root -g)/@mosaicstack/mosaic/framework/install.sh" ' +
+            '(MOSAIC_SYNC_ONLY=1 MOSAIC_INSTALL_MODE=keep)',
+        );
+      }
+    }
   });
 
 // ─── wizard ─────────────────────────────────────────────────────────────

packages/mosaic/src/commands/compose-contract.spec.ts

@@ -0,0 +1,118 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { mkdtempSync, mkdirSync, writeFileSync, rmSync, readFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { composeContract } from './launch.js';
+
+/**
+ * Composer unit test (R7/R8/R9): asserts the launcher-composed runtime contract
+ *
+ *   - includes the per-tier anchors (CONSTITUTION / AGENTS / USER / runtime),
+ *   - keeps the CONSTITUTION block byte-equal to the on-disk file (Tier-3
+ *     byte-equality — the bare-launch fallback read must match what is injected),
+ *   - merges `*.local.md` operator overlays as deltas-by-value, and omits them
+ *     entirely when absent (base-only),
+ *   - selects the correct per-harness RUNTIME.md.
+ *
+ * `composeContract` takes `mosaicHome` as a param, so each test runs against an
+ * isolated fixture home. We also chdir to an empty temp cwd so the cwd-relative
+ * mission/PRD blocks contribute nothing (deterministic output).
+ */
+
+const CONSTITUTION = '# CONSTITUTION\n\nGATE-1: the non-negotiable law.\n';
+const AGENTS = '# Mosaic Agent Dispatcher\n\nLoad order + guide router.\n';
+const USER = '# operator\n\nName: Test Operator\n';
+const TOOLS = '# tools index\n';
+
+function makeHome(): { home: string; root: string } {
+  const root = mkdtempSync(join(tmpdir(), 'mosaic-compose-'));
+  const home = join(root, 'mosaic-home');
+  for (const h of ['claude', 'codex', 'opencode', 'pi']) {
+    mkdirSync(join(home, 'runtime', h), { recursive: true });
+    writeFileSync(join(home, 'runtime', h, 'RUNTIME.md'), `# ${h} runtime contract\n`);
+  }
+  writeFileSync(join(home, 'CONSTITUTION.md'), CONSTITUTION);
+  writeFileSync(join(home, 'AGENTS.md'), AGENTS);
+  writeFileSync(join(home, 'USER.md'), USER);
+  writeFileSync(join(home, 'TOOLS.md'), TOOLS);
+  return { home, root };
+}
+
+describe('composeContract — overlay composer', () => {
+  let fixture: ReturnType<typeof makeHome>;
+  let prevCwd: string;
+  let cwdDir: string;
+
+  beforeEach(() => {
+    fixture = makeHome();
+    prevCwd = process.cwd();
+    cwdDir = mkdtempSync(join(tmpdir(), 'mosaic-cwd-'));
+    process.chdir(cwdDir); // neutralize cwd-relative mission/PRD blocks
+  });
+
+  afterEach(() => {
+    process.chdir(prevCwd);
+    rmSync(fixture.root, { recursive: true, force: true });
+    rmSync(cwdDir, { recursive: true, force: true });
+  });
+
+  it('includes the per-tier anchors and the selected harness runtime', () => {
+    const out = composeContract('claude', fixture.home);
+    expect(out).toContain('GATE-1: the non-negotiable law.'); // L0
+    expect(out).toContain('Mosaic Agent Dispatcher'); // AGENTS
+    expect(out).toContain('# User Profile'); // USER header
+    expect(out).toContain('Name: Test Operator'); // USER body
+    expect(out).toContain('# Runtime-Specific Contract');
+    expect(out).toContain('# claude runtime contract');
+  });
+
+  it('keeps the CONSTITUTION block byte-equal to the on-disk file (Tier-3)', () => {
+    const out = composeContract('pi', fixture.home);
+    const onDisk = readFileSync(join(fixture.home, 'CONSTITUTION.md'), 'utf-8');
+    // The injected L0 must be a byte-equal substring of the composed blob, so a
+    // bare-launch fallback read of CONSTITUTION.md matches what was injected.
+    expect(out.includes(onDisk)).toBe(true);
+  });
+
+  it('is base-only when no *.local overlays exist', () => {
+    const out = composeContract('claude', fixture.home);
+    expect(out).not.toContain('# Operator Overlays');
+    expect(out).not.toContain('Operator Overlay (USER.local.md)');
+    expect(out).not.toContain('Persona Overlay');
+    expect(out).not.toContain('Standards Overlay');
+  });
+
+  it('merges USER.local.md directly under the operator profile', () => {
+    writeFileSync(join(fixture.home, 'USER.local.md'), 'Prefer terse status updates.\n');
+    const out = composeContract('claude', fixture.home);
+    expect(out).toContain('## Operator Overlay (USER.local.md)');
+    expect(out).toContain('Prefer terse status updates.');
+    // Overlay appears AFTER its base profile.
+    expect(out.indexOf('# User Profile')).toBeLessThan(
+      out.indexOf('## Operator Overlay (USER.local.md)'),
+    );
+  });
+
+  it('merges SOUL.local.md + STANDARDS.local.md as deltas in the Operator Overlays block', () => {
+    writeFileSync(join(fixture.home, 'SOUL.local.md'), 'Tone: dry and direct.\n');
+    writeFileSync(join(fixture.home, 'STANDARDS.local.md'), 'Require 90% coverage on auth code.\n');
+    const out = composeContract('claude', fixture.home);
+    expect(out).toContain('# Operator Overlays');
+    expect(out).toContain('## Persona Overlay (SOUL.local.md)');
+    expect(out).toContain('Tone: dry and direct.');
+    expect(out).toContain('## Standards Overlay (STANDARDS.local.md)');
+    expect(out).toContain('Require 90% coverage on auth code.');
+  });
+
+  it('ignores whitespace-only *.local overlays (no empty overlay section)', () => {
+    writeFileSync(join(fixture.home, 'SOUL.local.md'), '   \n\n');
+    const out = composeContract('claude', fixture.home);
+    expect(out).not.toContain('# Operator Overlays');
+  });
+
+  it('selects a different RUNTIME.md per harness', () => {
+    expect(composeContract('codex', fixture.home)).toContain('# codex runtime contract');
+    expect(composeContract('pi', fixture.home)).toContain('# pi runtime contract');
+    expect(composeContract('codex', fixture.home)).not.toContain('# pi runtime contract');
+  });
+});

packages/mosaic/src/commands/fleet.ts

@@ -1,9 +1,10 @@
 import { constants } from 'node:fs';
-import { access, chmod, copyFile, mkdir, readFile, writeFile } from 'node:fs/promises';
+import { access, chmod, copyFile, mkdir, readFile, unlink, writeFile } from 'node:fs/promises';
 import { homedir, hostname, userInfo } from 'node:os';
 import { dirname, join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import { spawn } from 'node:child_process';
+import * as readline from 'node:readline';
 import type { Command } from 'commander';
 import YAML from 'yaml';
 
@@ -41,6 +42,11 @@ export interface FleetCommandDeps {
   sleepFn?: SleepFn;
   mosaicHome?: string;
   frameworkRoot?: string;
+  /**
+   * Injectable TTY check for `fleet init` wizard. Defaults to process.stdin.isTTY.
+   * Tests stub this to simulate interactive or non-interactive environments.
+   */
+  isStdinTTY?: boolean;
 }
 
 interface RawFleetRoster {
@@ -146,13 +152,16 @@ export function resolveFleetPaths(mosaicHome = defaultMosaicHome()): FleetPaths
 }
 
 function defaultMosaicHome(): string {
-  return join(homedir(), '.config', 'mosaic');
+  // Honor MOSAIC_HOME so the reader matches the writer sidecar (and the launcher),
+  // even when MOSAIC_HOME is set in the shell without an explicit --mosaic-home flag.
+  return process.env.MOSAIC_HOME ?? join(homedir(), '.config', 'mosaic');
 }
 
 function assertDefaultMosaicHomeForSystemd(mosaicHome: string): void {
-  if (resolve(mosaicHome) !== resolve(defaultMosaicHome())) {
+  const literalHome = join(homedir(), '.config', 'mosaic');
+  if (resolve(mosaicHome) !== resolve(literalHome)) {
     throw new Error(
-      `install-systemd only supports the default Mosaic home (${defaultMosaicHome()}) because the user systemd units use %h/.config/mosaic paths.`,
+      `install-systemd only supports the default Mosaic home (${literalHome}) because the user systemd units use %h/.config/mosaic paths.`,
     );
   }
 }
@@ -210,6 +219,102 @@ export function buildFleetServiceCommand(action: FleetServiceAction, agentName?:
   return ['systemctl', '--user', action, service];
 }
 
+/**
+ * Returns the systemctl --user enable command for a given unit.
+ * Used by the install auto-enable step to persist units across reboots.
+ */
+export function buildSystemdEnableCommand(unit: string): string[] {
+  return ['systemctl', '--user', 'enable', unit];
+}
+
+/**
+ * Returns the systemctl --user disable command for a given unit.
+ * Used by `fleet remove` so a removed agent's enabled unit cannot resurrect on
+ * boot pointing at deleted config (boot-survival symmetry with enable-on-add).
+ */
+export function buildSystemdDisableCommand(unit: string): string[] {
+  return ['systemctl', '--user', 'disable', unit];
+}
+
+/**
+ * Returns the loginctl enable-linger command for a given user.
+ * Linger allows user systemd services to survive logout.
+ */
+export function buildEnableLingerCommand(user: string): string[] {
+  return ['loginctl', 'enable-linger', user];
+}
+
+/**
+ * Enable fleet units for boot-survival after install.
+ * Non-fatal: if systemctl enable returns non-zero, a warning is printed and we continue.
+ * If opts.enable === false (--no-enable flag), the whole step is skipped.
+ */
+export async function enableFleetUnits(
+  runner: CommandRunner,
+  roster: FleetRoster,
+  opts: { enable?: boolean },
+): Promise<void> {
+  if (opts.enable === false) {
+    return;
+  }
+  try {
+    let succeeded = 0;
+    let failed = 0;
+
+    const holderResult = await runner(
+      ...splitCommand(buildSystemdEnableCommand('mosaic-tmux-holder.service')),
+    );
+    if (holderResult.exitCode === 0) {
+      succeeded++;
+    } else {
+      failed++;
+      process.stderr.write(
+        `Warning: could not enable mosaic-tmux-holder.service: ${holderResult.stderr || holderResult.stdout || 'non-zero exit'}\n`,
+      );
+    }
+
+    for (const agent of roster.agents) {
+      const unit = `mosaic-agent@${agent.name}.service`;
+      const result = await runner(...splitCommand(buildSystemdEnableCommand(unit)));
+      if (result.exitCode === 0) {
+        succeeded++;
+      } else {
+        failed++;
+        process.stderr.write(
+          `Warning: could not enable ${unit}: ${result.stderr || result.stdout || 'non-zero exit'}\n`,
+        );
+      }
+    }
+
+    if (succeeded > 0) {
+      console.log(`Enabled ${succeeded} unit(s) for boot-survival.`);
+    }
+    if (failed > 0) {
+      process.stderr.write(
+        `Warning: ${failed} unit(s) could not be enabled (systemctl unavailable?). Run manually if needed.\n`,
+      );
+    }
+
+    // Best-effort linger
+    let username: string;
+    try {
+      username = userInfo().username;
+    } catch {
+      username = process.env['USER'] ?? process.env['LOGNAME'] ?? 'unknown';
+    }
+    const lingerResult = await runner(...splitCommand(buildEnableLingerCommand(username)));
+    if (lingerResult.exitCode !== 0) {
+      process.stderr.write(
+        `Hint: run 'loginctl enable-linger ${username}' as root to survive logout.\n`,
+      );
+    }
+  } catch (err) {
+    process.stderr.write(
+      `Warning: auto-enable step failed unexpectedly: ${err instanceof Error ? err.message : String(err)}\n`,
+    );
+  }
+}
+
 export function buildAgentSendCommand(
   paths: FleetPaths,
   agentName: string,
@@ -275,6 +380,16 @@ export function buildAgentTailCommand(
 // ---------------------------------------------------------------------------
 
 export const HEARTBEAT_INTERVAL_MS = 15_000;
+
+/**
+ * Heartbeat interval in ms, honoring MOSAIC_HEARTBEAT_INTERVAL (seconds) so the
+ * `fleet ps` freshness threshold matches the writer sidecar's actual cadence
+ * (start-agent-session.sh). Falls back to HEARTBEAT_INTERVAL_MS (15s).
+ */
+export function heartbeatIntervalMs(): number {
+  const sec = Number.parseInt(process.env.MOSAIC_HEARTBEAT_INTERVAL ?? '', 10);
+  return Number.isFinite(sec) && sec > 0 ? sec * 1000 : HEARTBEAT_INTERVAL_MS;
+}
 export const HEARTBEAT_HEALTHY_MULTIPLIER = 3;
 
 export interface HeartbeatInfo {
@@ -284,6 +399,8 @@ export interface HeartbeatInfo {
   /** healthy | stale | unknown */
   health: 'healthy' | 'stale' | 'unknown';
   ageMs: number | null;
+  /** Model id the runtime self-reported in its heartbeat (native HB only), else null. */
+  model: string | null;
 }
 
 export interface AgentPsRow {
@@ -302,6 +419,10 @@ export interface AgentPsRow {
   driftFlag: boolean;
   /** active but UnitFileState=disabled */
   bootEnableWarning: boolean;
+  /** true = came from roster; false = found on socket but not in roster */
+  managed: boolean;
+  /** "roster" = defined in roster.yaml; "socket" = discovered via tmux list-sessions */
+  source: 'roster' | 'socket';
 }
 
 /**
@@ -344,11 +465,34 @@ export function buildTmuxListPanesCommand(
   ];
 }
 
+/**
+ * Returns the tmux list-sessions command to enumerate all sessions on a socket.
+ * Format: `tmux -L <socket> list-sessions -F '#{session_name}'`
+ * Used to discover ad-hoc sessions that are not in the roster.
+ */
+export function buildTmuxListSessionsCommand(socketName = DEFAULT_SOCKET_NAME): string[] {
+  return ['tmux', '-L', socketName, 'list-sessions', '-F', '#{session_name}'];
+}
+
+/**
+ * Parse the output of `tmux list-sessions -F '#{session_name}'` into an array of session names.
+ * Returns an empty array on empty/blank output.
+ */
+export function parseTmuxListSessions(output: string): string[] {
+  return output
+    .split('\n')
+    .map((line) => line.trim())
+    .filter((line) => line.length > 0);
+}
+
 /**
  * Returns the heartbeat file path for an agent.
  */
 export function heartbeatPath(agentName: string, mosaicHome = defaultMosaicHome()): string {
-  return join(mosaicHome, 'fleet', 'run', `${agentName}.hb`);
+  // Honor MOSAIC_HEARTBEAT_RUN_DIR (the writer sidecar's override); otherwise the
+  // canonical <mosaicHome>/fleet/run. Keeps reader and writer on the same path.
+  const runDir = process.env.MOSAIC_HEARTBEAT_RUN_DIR ?? join(mosaicHome, 'fleet', 'run');
+  return join(runDir, `${agentName}.hb`);
 }
 
 /**
@@ -357,15 +501,17 @@ export function heartbeatPath(agentName: string, mosaicHome = defaultMosaicHome(
  *   ts=<iso8601>
  *   pid=<pid>
  *   status=<ok|busy>
+ *   model=<model-id>   (optional — native runtime heartbeats self-report it)
  */
 export function parseHeartbeat(content: string | null, nowMs = Date.now()): HeartbeatInfo {
   if (content === null) {
-    return { ts: null, pid: null, status: null, health: 'unknown', ageMs: null };
+    return { ts: null, pid: null, status: null, health: 'unknown', ageMs: null, model: null };
   }
   const lines = content.split('\n');
   let ts: Date | null = null;
   let pid: number | null = null;
   let status: 'ok' | 'busy' | null = null;
+  let model: string | null = null;
   for (const line of lines) {
     const [key, ...rest] = line.split('=');
     const val = rest.join('=').trim();
@@ -377,16 +523,18 @@ export function parseHeartbeat(content: string | null, nowMs = Date.now()): Hear
       if (Number.isFinite(n)) pid = n;
     } else if (key === 'status' && (val === 'ok' || val === 'busy')) {
       status = val;
+    } else if (key === 'model' && val) {
+      model = val;
     }
   }
-  const thresholdMs = HEARTBEAT_INTERVAL_MS * HEARTBEAT_HEALTHY_MULTIPLIER;
+  const thresholdMs = heartbeatIntervalMs() * HEARTBEAT_HEALTHY_MULTIPLIER;
   let health: 'healthy' | 'stale' | 'unknown' = 'unknown';
   let ageMs: number | null = null;
   if (ts !== null) {
     ageMs = nowMs - ts.getTime();
     health = ageMs <= thresholdMs ? 'healthy' : 'stale';
   }
-  return { ts, pid, status, health, ageMs };
+  return { ts, pid, status, health, ageMs, model };
 }
 
 /**
@@ -437,32 +585,41 @@ export function parseTmuxListPanes(
   return { pid, command, dead, idleSeconds };
 }
 
+/**
+ * Maps each known runtime to the set of acceptable pane commands.
+ * A pane running any of these commands for the given runtime is NOT considered drifted.
+ * Runtimes launched via `mosaic yolo` wrap in node, so 'node' is acceptable for most.
+ * The dogfood runtime accepts python3/python (the canary-pi dogfood stub).
+ */
+export const RUNTIME_ACCEPTABLE_COMMANDS: Record<string, readonly string[]> = {
+  claude: ['claude', 'node'],
+  codex: ['codex', 'node'],
+  opencode: ['opencode', 'node'],
+  pi: ['pi', 'node'],
+  dogfood: ['python3', 'python'],
+};
+
 /**
  * Determine if there is a runtime drift: roster says one runtime but the pane
  * is actually running something from a different runtime. We detect this by
- * checking if the pane command doesn't match a known canonical command for the
+ * checking if the pane command doesn't match a known acceptable command for the
  * roster's declared runtime.
  *
- * Known canonical commands per runtime:
+ * Known acceptable commands per runtime (see RUNTIME_ACCEPTABLE_COMMANDS):
- *   claude → claude
+ *   claude   → claude, node  (node covers mosaic yolo wrapper)
- *   codex  → codex
+ *   codex    → codex, node
- *   opencode → opencode
+ *   opencode → opencode, node
- *   pi     → pi
+ *   pi       → pi, node      (python3 still flags drift for canary-pi dogfood stub)
+ *   dogfood  → python3, python
  *
  * If the pane is running something else (e.g., python3/dogfood-agent.py) for
  * an agent whose roster runtime is "pi", that's a drift.
  */
 export function detectDrift(rosterRuntime: string, paneCommand: string | null): boolean {
   if (!paneCommand) return false;
-  const knownCommands: Record<string, string[]> = {
+  const acceptable = RUNTIME_ACCEPTABLE_COMMANDS[rosterRuntime];
-    claude: ['claude'],
+  if (!acceptable) return false;
-    codex: ['codex'],
+  return !acceptable.includes(paneCommand);
-    opencode: ['opencode'],
-    pi: ['pi'],
-  };
-  const expected = knownCommands[rosterRuntime];
-  if (!expected) return false;
-  return !expected.includes(paneCommand);
 }
 
 /**
@@ -679,19 +836,42 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
   cmd
     .command('init')
     .description('Initialize a local fleet roster')
-    .option('--profile <name>', 'Roster profile: minimal or local-canary', 'minimal')
+    .option(
+      '--profile <name>',
+      `Roster profile: ${FLEET_PROFILES.join(', ')} (skips interactive wizard)`,
+    )
     .option('--write', 'Write the roster to Mosaic home')
     .option('--force', 'Overwrite an existing roster when used with --write')
-    .action(async (opts: { profile: string; write?: boolean; force?: boolean }) => {
+    .action(async (opts: { profile?: string; write?: boolean; force?: boolean }) => {
       const commandOpts = cmd.opts<{ mosaicHome: string; roster?: string }>();
       const activePaths = resolveFleetPaths(commandOpts.mosaicHome);
-      const profile = parseInitProfile(opts.profile);
+
-      const source = join(frameworkRoot, 'fleet', 'examples', `${profile}.yaml`);
+      let profile: FleetProfile;
+      if (opts.profile !== undefined) {
+        // Explicit --profile flag: validate and use it (non-interactive path).
+        profile = parseInitProfile(opts.profile);
+      } else {
+        // No --profile: use wizard when stdin is a TTY, else default to 'general'.
+        const isTTY = deps.isStdinTTY ?? process.stdin.isTTY ?? false;
+        if (isTTY) {
+          profile = await promptFleetProfile();
+        } else {
+          process.stderr.write(
+            'Note: stdin is not a TTY; defaulting to fleet profile "general". ' +
+              'Use --profile <name> to select a different preset.\n',
+          );
+          profile = 'general';
+        }
+      }
+
+      const source = join(frameworkRoot, 'fleet', 'examples', resolvePresetFilename(profile));
       const content = await readFile(source, 'utf8');
+
       if (!opts.write) {
         console.log(content.trimEnd());
         return;
       }
+
       const destination = commandOpts.roster ?? activePaths.rosterPath;
       if (!opts.force && (await canRead(destination))) {
         throw new Error(
@@ -700,18 +880,57 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
       }
       await mkdir(dirname(destination), { recursive: true });
       await writeFile(destination, content);
-      console.log(`Wrote fleet roster: ${destination}`);
+
+      // Guarantee the two-agent floor: exactly one orchestrator AND at least
+      // one enhancer for every profile except the sanctioned no-orchestrator
+      // `minimal` preset. A mismatch means a corrupted/edited preset — fail hard
+      // rather than write a malformed fleet.
+      const written = await loadFleetRoster(destination);
+      const orchCount = countOrchestrators(written);
+      const enhancerCount = countEnhancers(written);
+      if (profile === 'minimal') {
+        console.log(
+          `Initialized ${profile} fleet: ${written.agents.length} agent(s) (no orchestrator). Next: mosaic fleet install`,
+        );
+      } else if (orchCount !== 1) {
+        throw new Error(
+          `Fleet init failed: the "${profile}" roster has ${orchCount} orchestrator agent(s), ` +
+            `expected exactly 1 (R5). The preset may be corrupted — re-install the framework.`,
+        );
+      } else if (enhancerCount < 1) {
+        throw new Error(
+          `Fleet init failed: the "${profile}" roster has no enhancer agent. Every fleet keeps an ` +
+            `orchestrator + enhancer minimum (two-agent floor). The preset may be corrupted — ` +
+            `re-install the framework.`,
+        );
+      } else {
+        const workerCount = written.agents.length - 1 - enhancerCount;
+        console.log(
+          `Initialized ${profile} fleet: 1 orchestrator + ${enhancerCount} enhancer(s) + ` +
+            `${workerCount} worker(s). Next: mosaic fleet install`,
+        );
+      }
     });
 
   cmd
     .command('install')
     .description('Install local fleet tools and user systemd units')
-    .action(async () => installFleet(cmd, frameworkRoot));
+    .option('--no-enable', 'Skip enabling units for boot-survival')
+    .action(async (opts: { enable?: boolean }) => {
+      await installFleet(cmd, frameworkRoot);
+      const roster = await loadRosterForCommand(cmd);
+      await enableFleetUnits(runner, roster, opts);
+    });
 
   cmd
     .command('install-systemd')
     .description('Install local fleet tools and user systemd units')
-    .action(async () => installFleet(cmd, frameworkRoot));
+    .option('--no-enable', 'Skip enabling units for boot-survival')
+    .action(async (opts: { enable?: boolean }) => {
+      await installFleet(cmd, frameworkRoot);
+      const roster = await loadRosterForCommand(cmd);
+      await enableFleetUnits(runner, roster, opts);
+    });
 
   for (const action of ['start', 'stop', 'restart'] as const) {
     cmd
@@ -791,7 +1010,9 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
 
   cmd
     .command('ps')
-    .description('Show real-time status for all roster agents (systemd + tmux + heartbeat)')
+    .description(
+      'Show real-time status for all roster agents and unmanaged socket sessions (systemd + tmux + heartbeat)',
+    )
     .option('--json', 'Print JSON array')
     .action(async (opts: { json?: boolean }) => {
       const commandOpts = cmd.opts<{ mosaicHome: string; roster?: string }>();
@@ -802,6 +1023,9 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
 
       const rows: AgentPsRow[] = [];
 
+      // Build the set of roster agent names for quick lookup when filtering socket sessions.
+      const rosterAgentNames = new Set(roster.agents.map((a) => a.name));
+
       for (const agent of roster.agents) {
         // systemd show
         const showResult = await runner(...splitCommand(buildSystemdShowCommand(agent.name)));
@@ -842,9 +1066,75 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
           heartbeat: hb,
           driftFlag,
           bootEnableWarning,
+          managed: true,
+          source: 'roster',
         });
       }
 
+      // Enumerate all live sessions on the socket to surface unmanaged (ad-hoc) sessions.
+      // If list-sessions fails (socket not up), silently skip — show roster rows only.
+      try {
+        const listSessionsResult = await runner(
+          ...splitCommand(buildTmuxListSessionsCommand(roster.tmux.socketName)),
+        );
+        if (listSessionsResult.exitCode === 0) {
+          const socketSessions = parseTmuxListSessions(listSessionsResult.stdout);
+          const holderSession = roster.tmux.holderSession;
+
+          for (const sessionName of socketSessions) {
+            // Skip roster agents (already in rows) and the holder session (infrastructure).
+            if (rosterAgentNames.has(sessionName) || sessionName === holderSession) {
+              continue;
+            }
+
+            // tmux list-panes for pane info
+            const panesResult = await runner(
+              ...splitCommand(buildTmuxListPanesCommand(sessionName, roster.tmux.socketName)),
+            );
+            const paneInfo = parseTmuxListPanes(panesResult.stdout, nowMs);
+
+            // heartbeat — try reading the .hb file using the same path convention
+            const hbFile = heartbeatPath(sessionName, activePaths.mosaicHome);
+            let hbContent: string | null = null;
+            try {
+              hbContent = await readFile(hbFile, 'utf8');
+            } catch {
+              hbContent = null;
+            }
+            const hb = parseHeartbeat(hbContent, nowMs);
+
+            // systemd — check if mosaic-agent@<name>.service exists (usually inactive for ad-hoc)
+            const showResult = await runner(...splitCommand(buildSystemdShowCommand(sessionName)));
+            const sysInfo = parseSystemdShow(showResult.stdout);
+
+            const bootEnableWarning =
+              sysInfo.ActiveState === 'active' && sysInfo.UnitFileState === 'disabled';
+
+            rows.push({
+              name: sessionName,
+              tenant_id,
+              host,
+              // runtime unknown — not in roster
+              runtime: 'unknown',
+              systemdActive: sysInfo.ActiveState,
+              systemdEnabled: sysInfo.UnitFileState,
+              paneAlive: !paneInfo.dead,
+              panePid: paneInfo.pid,
+              paneCommand: paneInfo.command,
+              idleSeconds: paneInfo.idleSeconds,
+              heartbeat: hb,
+              // No roster runtime to compare — drift is not meaningful for unmanaged sessions
+              driftFlag: false,
+              bootEnableWarning,
+              managed: false,
+              source: 'socket',
+            });
+          }
+        }
+      } catch {
+        // list-sessions failed (socket missing or permission error) — show roster rows only
+      }
+
       if (opts.json) {
         console.log(JSON.stringify(rows, null, 2));
         return;
@@ -861,6 +1151,7 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
         'PID'.padEnd(8),
         'IDLE'.padEnd(8),
         'HB'.padEnd(12),
+        'MODEL'.padEnd(22),
         'FLAGS',
       ].join(' ');
       console.log(header);
@@ -875,7 +1166,9 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
           row.heartbeat.ageMs !== null
             ? `${Math.round(row.heartbeat.ageMs / 1000)}s/${row.heartbeat.health}`
             : `unknown`;
+        const model = row.heartbeat.model ?? '-';
         const flags: string[] = [];
+        if (!row.managed) flags.push('UNMANAGED');
         if (row.driftFlag) flags.push('DRIFT');
         if (row.bootEnableWarning) flags.push('BOOT-ENABLE');
 
@@ -890,12 +1183,157 @@ export function registerFleetCommand(program: Command, deps: FleetCommandDeps =
             pid.padEnd(8),
             idle.padEnd(8),
             hbAge.padEnd(12),
+            model.padEnd(22),
             flags.join(','),
           ].join(' '),
         );
       }
     });
 
+  cmd
+    .command('add <name>')
+    .description('Add a new agent to the fleet roster and optionally start it')
+    .requiredOption('--runtime <runtime>', `Agent runtime (${VALID_FLEET_RUNTIMES.join(', ')})`)
+    .requiredOption('--class <class>', 'Agent class (e.g. worker, orchestrator, canary)')
+    .option('--model <hint>', 'Model hint for the agent')
+    .option('--working-dir <path>', 'Working directory for the agent')
+    .option('--no-start', 'Skip starting the agent after adding')
+    .action(
+      async (
+        name: string,
+        opts: {
+          runtime: string;
+          class: string;
+          model?: string;
+          workingDir?: string;
+          start: boolean;
+        },
+      ) => {
+        if (!VALID_FLEET_RUNTIMES.includes(opts.runtime)) {
+          throw new Error(
+            `Invalid runtime "${opts.runtime}". Valid runtimes: ${VALID_FLEET_RUNTIMES.join(', ')}.`,
+          );
+        }
+        const commandOpts = cmd.opts<{ mosaicHome: string; roster?: string }>();
+        const activePaths = resolveFleetPaths(commandOpts.mosaicHome);
+        const rosterPath = await resolveRosterPath(commandOpts.mosaicHome, commandOpts.roster);
+        const roster = await loadFleetRoster(rosterPath);
+
+        const newAgent: FleetAgent = {
+          name,
+          runtime: opts.runtime,
+          className: opts.class,
+          ...(opts.workingDir !== undefined && { workingDirectory: opts.workingDir }),
+          ...(opts.model !== undefined && { modelHint: opts.model }),
+        };
+
+        const updatedRoster = addAgentToRoster(roster, newAgent);
+        await writeFile(rosterPath, serializeRosterToYaml(updatedRoster));
+
+        const envPath = join(activePaths.agentEnvDir, `${name}.env`);
+        const existingEnv = (await canRead(envPath)) ? await readFile(envPath, 'utf8') : undefined;
+        await mkdir(activePaths.agentEnvDir, { recursive: true });
+        await writeFile(
+          envPath,
+          mergeAgentEnv(generateAgentEnv(updatedRoster, newAgent), existingEnv),
+        );
+
+        console.log(`Added ${name} (${opts.runtime}/${opts.class}) to the fleet.`);
+
+        // Enable the unit for boot-survival (non-fatal) — symmetry with
+        // disable-on-remove. Independent of --start so a queued agent still
+        // survives a reboot once its unit exists.
+        try {
+          const enableResult = await runner(
+            ...splitCommand(buildSystemdEnableCommand(`mosaic-agent@${name}.service`)),
+          );
+          if (enableResult.exitCode !== 0) {
+            process.stderr.write(
+              `Warning: could not enable mosaic-agent@${name}.service: ${enableResult.stderr || enableResult.stdout || 'non-zero exit'}\n`,
+            );
+          }
+        } catch (err) {
+          process.stderr.write(
+            `Warning: enable command failed for ${name}: ${err instanceof Error ? err.message : String(err)}\n`,
+          );
+        }
+
+        if (opts.start !== false) {
+          await runChecked(runner, buildFleetServiceCommand('start', name));
+          console.log(`Started mosaic-agent@${name}.service.`);
+        } else {
+          console.log(`Agent queued (--no-start); run: mosaic fleet start ${name}`);
+        }
+      },
+    );
+
+  cmd
+    .command('remove <name>')
+    .description('Remove an agent from the fleet roster')
+    .option('--keep-files', 'Skip deleting env and heartbeat files')
+    .action(async (name: string, opts: { keepFiles?: boolean }) => {
+      const commandOpts = cmd.opts<{ mosaicHome: string; roster?: string }>();
+      const activePaths = resolveFleetPaths(commandOpts.mosaicHome);
+      const rosterPath = await resolveRosterPath(commandOpts.mosaicHome, commandOpts.roster);
+      const roster = await loadFleetRoster(rosterPath);
+
+      // Guard: throws if removing leaves 0 orchestrators or agent not in roster
+      const updatedRoster = removeAgentFromRoster(roster, name);
+
+      // Stop agent (non-fatal)
+      try {
+        const stopResult = await runner(...splitCommand(buildFleetServiceCommand('stop', name)));
+        if (stopResult.exitCode !== 0) {
+          process.stderr.write(
+            `Warning: could not stop mosaic-agent@${name}.service: ${stopResult.stderr || stopResult.stdout || 'non-zero exit'}\n`,
+          );
+        }
+      } catch (err) {
+        process.stderr.write(
+          `Warning: stop command failed for ${name}: ${err instanceof Error ? err.message : String(err)}\n`,
+        );
+      }
+
+      // Disable the unit (non-fatal) so an enabled instance cannot resurrect on
+      // boot pointing at the now-deleted config — boot-survival symmetry with
+      // enable-on-add. Skipped only when --keep-files keeps the config in place.
+      if (!opts.keepFiles) {
+        try {
+          const disableResult = await runner(
+            ...splitCommand(buildSystemdDisableCommand(`mosaic-agent@${name}.service`)),
+          );
+          if (disableResult.exitCode !== 0) {
+            process.stderr.write(
+              `Warning: could not disable mosaic-agent@${name}.service: ${disableResult.stderr || disableResult.stdout || 'non-zero exit'}\n`,
+            );
+          }
+        } catch (err) {
+          process.stderr.write(
+            `Warning: disable command failed for ${name}: ${err instanceof Error ? err.message : String(err)}\n`,
+          );
+        }
+      }
+
+      // Write updated roster
+      await writeFile(rosterPath, serializeRosterToYaml(updatedRoster));
+
+      // Delete env and heartbeat files (best-effort, non-fatal)
+      if (!opts.keepFiles) {
+        try {
+          await unlink(join(activePaths.agentEnvDir, `${name}.env`));
+        } catch {
+          // best-effort
+        }
+        try {
+          await unlink(heartbeatPath(name, activePaths.mosaicHome));
+        } catch {
+          // best-effort
+        }
+      }
+
+      console.log(`Removed ${name} from the fleet.`);
+    });
+
   return cmd;
 }
 
@@ -1075,15 +1513,19 @@ export function registerFleetAgentCommands(
 
       await runChecked(runner, buildAgentWatchCreateViewerCommand(agent, viewerName, socketName));
 
+      let exitCode = 0;
+      try {
         const [bin, args] = splitCommand(buildAgentWatchAttachCommand(viewerName, socketName));
-      const exitCode = await iRunner(bin, args);
+        exitCode = await iRunner(bin, args);
-
+      } finally {
-      // Best-effort cleanup of the viewer session regardless of how the user detached.
+        // ALWAYS clean up the viewer session — even if attach threw or the process was
-      // Errors here are intentionally suppressed — the agent session is unaffected.
+        // interrupted — so stale grouped *-watch-* sessions never accumulate. Errors here
+        // are intentionally suppressed; the agent session is unaffected.
         const killResult = await runner(
           ...splitCommand(buildAgentWatchKillViewerCommand(viewerName, socketName)),
         );
-      void killResult; // result is intentionally ignored
+        void killResult;
+      }
 
       if (exitCode !== 0) {
         process.exitCode = exitCode;
@@ -1466,11 +1908,213 @@ function splitCommand(command: string[]): [string, string[]] {
   return [bin, args];
 }
 
-function parseInitProfile(profile: string): 'minimal' | 'local-canary' {
+/** All supported fleet profile names. */
-  if (profile === 'minimal' || profile === 'local-canary') {
+export type FleetProfile =
-    return profile;
+  | 'general'
+  | 'coding'
+  | 'research'
+  | 'hybrid'
+  | 'minimal'
+  | 'local-canary';
+
+/** The list of all valid fleet profile names, for wizard menus and error messages. */
+export const FLEET_PROFILES: readonly FleetProfile[] = [
+  'general',
+  'coding',
+  'research',
+  'hybrid',
+  'minimal',
+  'local-canary',
+];
+
+/**
+ * Maps a fleet profile name to its example YAML filename (without the path).
+ * Pure function — testable without I/O.
+ */
+export function resolvePresetFilename(profile: FleetProfile): string {
+  return `${profile}.yaml`;
+}
+
+/**
+ * Validate and normalise a fleet profile name string.
+ * Throws with a clear message on unknown values.
+ */
+export function parseInitProfile(profile: string): FleetProfile {
+  if ((FLEET_PROFILES as readonly string[]).includes(profile)) {
+    return profile as FleetProfile;
   }
-  throw new Error(`Unsupported fleet profile "${profile}". Use: minimal, local-canary.`);
+  throw new Error(`Unsupported fleet profile "${profile}". Use: ${FLEET_PROFILES.join(', ')}.`);
+}
+
+/**
+ * Count orchestrator agents in a parsed roster.
+ * Returns the count; callers assert === 1.
+ */
+export function countOrchestrators(roster: FleetRoster): number {
+  return roster.agents.filter((a) => a.className === 'orchestrator').length;
+}
+
+/**
+ * Count enhancer agents in a parsed roster. The two-agent floor (north-star)
+ * requires every non-minimal fleet to carry at least one enhancer alongside the
+ * sole orchestrator.
+ */
+export function countEnhancers(roster: FleetRoster): number {
+  return roster.agents.filter((a) => a.className === 'enhancer').length;
+}
+
+/** Valid runtime identifiers for fleet agents. */
+export const VALID_FLEET_RUNTIMES: readonly string[] = [
+  'pi',
+  'claude',
+  'codex',
+  'opencode',
+  'dogfood',
+];
+
+/**
+ * Add a new agent to a fleet roster (immutable — returns a new FleetRoster).
+ * Throws on invalid name, duplicate name.
+ */
+export function addAgentToRoster(roster: FleetRoster, agent: FleetAgent): FleetRoster {
+  if (!agent.name || !/^[A-Za-z0-9_.-]+$/.test(agent.name)) {
+    throw new Error(`Invalid fleet agent name: ${agent.name || '<empty>'}`);
+  }
+  if (roster.agents.some((a) => a.name === agent.name)) {
+    throw new Error(`Agent "${agent.name}" already exists in the fleet roster.`);
+  }
+  return {
+    ...roster,
+    agents: [...roster.agents, agent],
+  };
+}
+
+/**
+ * Remove an agent from a fleet roster (immutable — returns a new FleetRoster).
+ * Throws if the agent is not found, or if removal would leave zero orchestrators.
+ */
+export function removeAgentFromRoster(roster: FleetRoster, name: string): FleetRoster {
+  const agent = roster.agents.find((a) => a.name === name);
+  if (!agent) {
+    throw new Error(`Agent "${name}" is not in the fleet roster.`);
+  }
+  const remaining = roster.agents.filter((a) => a.name !== name);
+  const remainingOrchCount = remaining.filter((a) => a.className === 'orchestrator').length;
+  if (remainingOrchCount === 0 && agent.className === 'orchestrator') {
+    throw new Error(
+      `Cannot remove agent "${name}": it is the sole orchestrator. Add another orchestrator first (R5).`,
+    );
+  }
+  // Two-agent floor: never drop the last enhancer (the continuous-improvement
+  // loop). Symmetric with the sole-orchestrator guard.
+  const remainingEnhancerCount = remaining.filter((a) => a.className === 'enhancer').length;
+  if (remainingEnhancerCount === 0 && agent.className === 'enhancer') {
+    throw new Error(
+      `Cannot remove agent "${name}": it is the sole enhancer. Every fleet keeps at least one ` +
+        `enhancer (two-agent floor). Add another enhancer first.`,
+    );
+  }
+  return {
+    ...roster,
+    agents: remaining,
+  };
+}
+
+/**
+ * Serialize a FleetRoster to YAML text (snake_case keys).
+ * The output is parseable by loadFleetRoster.
+ */
+export function serializeRosterToYaml(roster: FleetRoster): string {
+  const agents = roster.agents.map((agent) => {
+    const raw: Record<string, unknown> = {
+      name: agent.name,
+      runtime: agent.runtime,
+      class: agent.className,
+    };
+    if (agent.workingDirectory !== undefined) {
+      raw['working_directory'] = agent.workingDirectory;
+    }
+    if (agent.modelHint !== undefined) {
+      raw['model_hint'] = agent.modelHint;
+    }
+    if (agent.persistentPersona !== undefined) {
+      raw['persistent_persona'] = agent.persistentPersona;
+    }
+    if (agent.resetBetweenTasks !== undefined) {
+      raw['reset_between_tasks'] = agent.resetBetweenTasks;
+    }
+    if (agent.kickstartTemplate !== undefined) {
+      raw['kickstart_template'] = agent.kickstartTemplate;
+    }
+    return raw;
+  });
+
+  const runtimes: Record<string, { reset_command: string }> = {};
+  for (const [runtime, config] of Object.entries(roster.runtimes)) {
+    runtimes[runtime] = { reset_command: config.resetCommand };
+  }
+
+  const raw: Record<string, unknown> = {
+    version: roster.version,
+    transport: roster.transport,
+    tmux: {
+      socket_name: roster.tmux.socketName,
+      holder_session: roster.tmux.holderSession,
+    },
+    defaults: {
+      working_directory: roster.defaults.workingDirectory,
+    },
+    runtimes,
+    agents,
+  };
+
+  return YAML.stringify(raw);
+}
+
+/**
+ * Prompt interactively for a fleet profile via stdin readline.
+ * AI-free: no LLM calls — pure readline menu.
+ * Resolves with the chosen profile string, or rejects on I/O error.
+ */
+function promptFleetProfile(): Promise<FleetProfile> {
+  return new Promise((resolve, reject) => {
+    const rl = readline.createInterface({ input: process.stdin, output: process.stdout });
+    const menu = [
+      '',
+      'Choose a fleet configuration type:',
+      '  1) general      — orchestrator + generalist worker',
+      '  2) coding       — orchestrator + coder0 + coder1 + reviewer',
+      '  3) research     — orchestrator + researcher0 + researcher1 + analyst',
+      '  4) hybrid       — orchestrator + coder0 + researcher0 + reviewer',
+      '  5) minimal      — single canary-pi agent (no orchestrator)',
+      '  6) local-canary — legacy canary preset with lead + coder + reviewer',
+      '',
+    ].join('\n');
+    process.stdout.write(menu);
+    rl.question('Enter number or name [1]: ', (answer) => {
+      rl.close();
+      const trimmed = answer.trim();
+      // Map numeric shortcut → name
+      const byNumber: Record<string, FleetProfile> = {
+        '1': 'general',
+        '2': 'coding',
+        '3': 'research',
+        '4': 'hybrid',
+        '5': 'minimal',
+        '6': 'local-canary',
+        '': 'general', // default on empty enter
+      };
+      if (trimmed in byNumber) {
+        resolve(byNumber[trimmed]!);
+        return;
+      }
+      try {
+        resolve(parseInitProfile(trimmed));
+      } catch (err) {
+        reject(err);
+      }
+    });
+  });
 }
 
 function writeCommandOutput(result: CommandResult): void {

packages/mosaic/src/commands/launch.ts

@@ -291,12 +291,23 @@ function buildPrdBlock(): string {
 
 // ─── Runtime prompt builder ──────────────────────────────────────────────────
 
-function buildRuntimePrompt(runtime: RuntimeName): string {
+/**
+ * Compose the full runtime contract for a harness: the resident-by-value core
+ * (CONSTITUTION + AGENTS + USER + TOOLS + runtime) plus operator overlays
+ * (`*.local.md` deltas), merged in precedence order so the model gets one
+ * pre-merged blob (DESIGN §3.2 / R7). Overlays are injected as deltas by value;
+ * base files keep their existing residency (USER injected; SOUL/STANDARDS are
+ * load-on-demand, so only their small `.local` deltas are injected here).
+ *
+ * `mosaicHome` is parameterized for testability; production callers use the
+ * module-level default.
+ */
+export function composeContract(runtime: RuntimeName, mosaicHome: string = MOSAIC_HOME): string {
   const runtimeContractPaths: Record<RuntimeName, string> = {
-    claude: join(MOSAIC_HOME, 'runtime', 'claude', 'RUNTIME.md'),
+    claude: join(mosaicHome, 'runtime', 'claude', 'RUNTIME.md'),
-    codex: join(MOSAIC_HOME, 'runtime', 'codex', 'RUNTIME.md'),
+    codex: join(mosaicHome, 'runtime', 'codex', 'RUNTIME.md'),
-    opencode: join(MOSAIC_HOME, 'runtime', 'opencode', 'RUNTIME.md'),
+    opencode: join(mosaicHome, 'runtime', 'opencode', 'RUNTIME.md'),
-    pi: join(MOSAIC_HOME, 'runtime', 'pi', 'RUNTIME.md'),
+    pi: join(mosaicHome, 'runtime', 'pi', 'RUNTIME.md'),
   };
 
   const runtimeFile = runtimeContractPaths[runtime];
@@ -331,27 +342,55 @@ For required push/merge/issue-close/release actions, execute without routine con
 `);
 
   // CONSTITUTION.md (L0 — the non-negotiable law; lead with it). Tolerant of
-  // pre-constitution installs that have not been re-seeded yet.
+  // pre-constitution installs that have not been re-seeded yet. Injected by
-  const constitution = readOptional(join(MOSAIC_HOME, 'CONSTITUTION.md'));
+  // value verbatim so the bare-launch fallback read is byte-equal (R8).
+  const constitution = readOptional(join(mosaicHome, 'CONSTITUTION.md'));
   if (constitution) parts.push(constitution);
 
   // AGENTS.md
-  parts.push(readFileSync(join(MOSAIC_HOME, 'AGENTS.md'), 'utf-8'));
+  parts.push(readFileSync(join(mosaicHome, 'AGENTS.md'), 'utf-8'));
 
-  // USER.md
+  // USER.md (+ USER.local.md operator overlay, appended directly under the
-  const user = readOptional(join(MOSAIC_HOME, 'USER.md'));
+  // profile its base owns).
+  const user = readOptional(join(mosaicHome, 'USER.md'));
   if (user) parts.push('\n\n# User Profile\n\n' + user);
+  const userLocal = readOptional(join(mosaicHome, 'USER.local.md'));
+  if (userLocal.trim()) {
+    parts.push('\n\n## Operator Overlay (USER.local.md)\n\n' + userLocal);
+  }
 
   // TOOLS.md
-  const tools = readOptional(join(MOSAIC_HOME, 'TOOLS.md'));
+  const tools = readOptional(join(mosaicHome, 'TOOLS.md'));
   if (tools) parts.push('\n\n# Machine Tools\n\n' + tools);
 
+  // Operator overlays whose base layers are load-on-demand (SOUL, STANDARDS):
+  // inject only the small `.local` delta by value so the customization reaches
+  // the model without re-injecting the full base prose (preserves the byte
+  // budget). Absent `.local` files → base-only, automatically (R7 §3.2).
+  const overlayBlocks: string[] = [];
+  const soulLocal = readOptional(join(mosaicHome, 'SOUL.local.md'));
+  if (soulLocal.trim()) {
+    overlayBlocks.push('## Persona Overlay (SOUL.local.md)\n\n' + soulLocal.trim());
+  }
+  const standardsLocal = readOptional(join(mosaicHome, 'STANDARDS.local.md'));
+  if (standardsLocal.trim()) {
+    overlayBlocks.push('## Standards Overlay (STANDARDS.local.md)\n\n' + standardsLocal.trim());
+  }
+  if (overlayBlocks.length > 0) {
+    parts.push('\n\n# Operator Overlays\n\n' + overlayBlocks.join('\n\n'));
+  }
+
   // Runtime-specific contract
   parts.push('\n\n# Runtime-Specific Contract\n\n' + readFileSync(runtimeFile, 'utf-8'));
 
   return parts.join('\n');
 }
 
+/** @deprecated internal alias — use composeContract. Retained for call-site clarity. */
+function buildRuntimePrompt(runtime: RuntimeName): string {
+  return composeContract(runtime);
+}
+
 // ─── Session lock ────────────────────────────────────────────────────────────
 
 function writeSessionLock(runtime: string): void {
@@ -976,6 +1015,22 @@ export function registerLaunchCommands(program: Command): void {
     launchRuntime(runtime, extraArgs, yolo);
   });
 
+  // compose-contract — emit the composed runtime contract (base + operator
+  // overlays) for a harness to stdout, without launching. For inspection,
+  // `mosaic doctor`, diffing, and the composer test (R7).
+  program
+    .command('compose-contract <harness>')
+    .description('Print the composed runtime contract (base + *.local overlays) for a harness')
+    .action((harness: string) => {
+      const valid: RuntimeName[] = ['claude', 'codex', 'opencode', 'pi'];
+      if (!valid.includes(harness as RuntimeName)) {
+        console.error(`Unknown harness '${harness}'. Expected one of: ${valid.join(', ')}.`);
+        process.exitCode = 64;
+        return;
+      }
+      process.stdout.write(composeContract(harness as RuntimeName));
+    });
+
   // Coord (mission orchestrator)
   program
     .command('coord')

packages/mosaic/src/config/file-adapter.test.ts

@@ -99,11 +99,8 @@ describe('FileConfigAdapter.syncFramework — defaults seeding', () => {
     );
   });
 
-  it('preserves existing contract files — never overwrites user customization', async () => {
+  it('overwrites framework-owned files (backup-once) but preserves user-seeded files', async () => {
-    // Also plant a root-level AGENTS.md in sourceDir so that `syncDirectory`
+    // Plant a root-level AGENTS.md in sourceDir so syncDirectory's preserve is exercised.
-    // itself (not just the seed loop) has something to try to overwrite.
-    // Without this, the test would silently pass even if preserve semantics
-    // were broken in syncDirectory.
     writeFileSync(join(fixture.sourceDir, 'AGENTS.md'), '# shipped AGENTS from source root\n');
 
     writeFileSync(join(fixture.mosaicHome, 'TOOLS.md'), '# user-customized TOOLS\n');
@@ -112,18 +109,50 @@ describe('FileConfigAdapter.syncFramework — defaults seeding', () => {
     const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
     await adapter.syncFramework('keep');
 
+    // User-seeded TOOLS.md is preserved.
     expect(readFileSync(join(fixture.mosaicHome, 'TOOLS.md'), 'utf-8')).toBe(
       '# user-customized TOOLS\n',
     );
-    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe(
+    // Framework-owned AGENTS.md is overwritten from defaults/ ...
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe('# AGENTS default\n');
+    // ... and the user's prior copy is backed up exactly once.
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md.pre-constitution.bak'), 'utf-8')).toBe(
       '# user-customized AGENTS\n',
     );
-    // And the missing contract file still gets seeded.
+    // Framework-owned STANDARDS.md (absent) gets installed.
     expect(readFileSync(join(fixture.mosaicHome, 'STANDARDS.md'), 'utf-8')).toContain(
       '# STANDARDS default',
     );
   });
 
+  it('backs up a divergent framework-owned file only once (idempotent across re-sync)', async () => {
+    writeFileSync(join(fixture.mosaicHome, 'AGENTS.md'), '# user-customized AGENTS\n');
+    const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
+
+    await adapter.syncFramework('keep'); // 1st: backup created, AGENTS overwritten
+    await adapter.syncFramework('keep'); // 2nd: AGENTS already == default, no new backup
+
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md.pre-constitution.bak'), 'utf-8')).toBe(
+      '# user-customized AGENTS\n',
+    );
+  });
+
+  it('preserves SOUL.md and credentials through a framework-owned overwrite', async () => {
+    writeFileSync(join(fixture.mosaicHome, 'SOUL.md'), '# my persona\n');
+    writeFileSync(join(fixture.mosaicHome, 'AGENTS.md'), '# user-customized AGENTS\n');
+    mkdirSync(join(fixture.mosaicHome, 'credentials'), { recursive: true });
+    writeFileSync(join(fixture.mosaicHome, 'credentials', 'c.json'), 'token\n');
+
+    const adapter = new FileConfigAdapter(fixture.mosaicHome, fixture.sourceDir);
+    await adapter.syncFramework('keep');
+
+    expect(readFileSync(join(fixture.mosaicHome, 'SOUL.md'), 'utf-8')).toBe('# my persona\n');
+    expect(readFileSync(join(fixture.mosaicHome, 'credentials', 'c.json'), 'utf-8')).toBe(
+      'token\n',
+    );
+    expect(readFileSync(join(fixture.mosaicHome, 'AGENTS.md'), 'utf-8')).toBe('# AGENTS default\n');
+  });
+
   it('is a no-op for seeding when defaults/ dir does not exist', async () => {
     rmSync(fixture.defaultsDir, { recursive: true });
 

packages/mosaic/src/config/file-adapter.ts

@@ -13,12 +13,17 @@ import { join } from 'node:path';
  * This list must match the explicit seed loop in
  * packages/mosaic/framework/install.sh.
  */
-export const DEFAULT_SEED_FILES = [
+// Framework-owned contract files: re-copied from defaults/ on every upgrade (a
-  'CONSTITUTION.md',
+// divergent existing copy is backed up once to <file>.pre-constitution.bak first).
-  'AGENTS.md',
+// MUST match FRAMEWORK_OWNED in packages/mosaic/framework/install.sh (append-friendly).
-  'STANDARDS.md',
+export const FRAMEWORK_OWNED_FILES = ['CONSTITUTION.md', 'AGENTS.md', 'STANDARDS.md'] as const;
-  'TOOLS.md',
+
-] as const;
+// User-seeded contract files: written once on first install, then owned by the user.
+// MUST match USER_SEEDED in packages/mosaic/framework/install.sh.
+export const USER_SEEDED_FILES = ['TOOLS.md'] as const;
+
+// Union, retained for callers/tests that assert the full seed set on a fresh install.
+export const DEFAULT_SEED_FILES = [...FRAMEWORK_OWNED_FILES, ...USER_SEEDED_FILES] as const;
 import type { ConfigService, ConfigSection, ResolvedConfig } from './config-service.js';
 import type { SoulConfig, UserConfig, ToolsConfig, InstallAction } from '../types.js';
 import { soulSchema, userSchema, toolsSchema } from './schemas.js';
@@ -159,6 +164,7 @@ export class FileConfigAdapter implements ConfigService {
     const preservePaths =
       action === 'keep' || action === 'reconfigure'
         ? [
+            'CONSTITUTION.md',
             'AGENTS.md',
             'SOUL.md',
             'USER.md',
@@ -175,10 +181,10 @@ export class FileConfigAdapter implements ConfigService {
       excludeGit: true,
     });
 
-    // Copy framework-contract files (AGENTS.md, STANDARDS.md, TOOLS.md)
+    // Reconcile framework-contract files from framework/defaults/ into the mosaic
-    // from framework/defaults/ into the mosaic home root if they don't
+    // home root: framework-owned files (CONSTITUTION/AGENTS/STANDARDS) are overwritten
-    // exist yet. These are written on first install only and are never
+    // every upgrade (backup-once); user-seeded files (TOOLS) are written on first
-    // overwritten afterwards — the user may have customized them.
+    // install only. Mirrors reconcile_framework_files() in install.sh.
     //
     // SOUL.md and USER.md are deliberately NOT seeded here. They are
     // generated from templates by the soul/user wizard stages with
@@ -186,7 +192,22 @@ export class FileConfigAdapter implements ConfigService {
     // identity flow and leak placeholder content into the mosaic home.
     const defaultsDir = join(this.sourceDir, 'defaults');
     if (existsSync(defaultsDir)) {
-      for (const entry of DEFAULT_SEED_FILES) {
+      // Framework-owned: overwrite from defaults/ every sync; back up a divergent
+      // existing copy ONCE to <file>.pre-constitution.bak before the first overwrite.
+      for (const entry of FRAMEWORK_OWNED_FILES) {
+        const src = join(defaultsDir, entry);
+        const dest = join(this.mosaicHome, entry);
+        if (!existsSync(src) || !statSync(src).isFile()) continue;
+        // Already current — skip to avoid mtime churn.
+        if (existsSync(dest) && readFileSync(src).equals(readFileSync(dest))) continue;
+        const bak = `${dest}.pre-constitution.bak`;
+        if (existsSync(dest) && !existsSync(bak)) {
+          copyFileSync(dest, bak);
+        }
+        copyFileSync(src, dest);
+      }
+      // User-seeded: write only if absent.
+      for (const entry of USER_SEEDED_FILES) {
         const src = join(defaultsDir, entry);
         const dest = join(this.mosaicHome, entry);
         if (existsSync(dest)) continue;

packages/mosaic/src/runtime/update-checker.reseed.spec.ts

@@ -0,0 +1,85 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import { mkdtempSync, mkdirSync, writeFileSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import {
+  buildReseedCommand,
+  buildRelaunchCommands,
+  readRosterAgentNames,
+  runFrameworkReseed,
+} from './update-checker.js';
+
+/**
+ * F3-m3 / R13: `mosaic update` re-seeds the framework + (opt-in) relaunches
+ * durable agents so shipped launcher/runtime changes activate. These cover the
+ * pure builders + the missing-installer guard (the exec path is integration).
+ */
+
+describe('buildReseedCommand', () => {
+  it('invokes the package install.sh in data-safe sync-only keep mode', () => {
+    const out = buildReseedCommand('/pkg/framework', '/home/u/.config/mosaic');
+    expect(out.installer).toBe('/pkg/framework/install.sh');
+    expect(out.command).toBe('bash /pkg/framework/install.sh');
+    expect(out.env).toEqual({
+      MOSAIC_SYNC_ONLY: '1',
+      MOSAIC_INSTALL_MODE: 'keep',
+      MOSAIC_HOME: '/home/u/.config/mosaic',
+    });
+  });
+});
+
+describe('buildRelaunchCommands', () => {
+  it('builds a systemctl --user restart per agent unit', () => {
+    expect(buildRelaunchCommands(['orchestrator', 'coder0'])).toEqual([
+      ['systemctl', '--user', 'restart', 'mosaic-agent@orchestrator.service'],
+      ['systemctl', '--user', 'restart', 'mosaic-agent@coder0.service'],
+    ]);
+  });
+
+  it('is empty for an empty roster', () => {
+    expect(buildRelaunchCommands([])).toEqual([]);
+  });
+});
+
+describe('readRosterAgentNames', () => {
+  let home: string;
+
+  beforeEach(() => {
+    home = mkdtempSync(join(tmpdir(), 'mosaic-roster-'));
+  });
+  afterEach(() => {
+    rmSync(home, { recursive: true, force: true });
+  });
+
+  it('returns [] when no roster exists', () => {
+    expect(readRosterAgentNames(home)).toEqual([]);
+  });
+
+  it('extracts agent names from roster.yaml', () => {
+    mkdirSync(join(home, 'fleet'), { recursive: true });
+    writeFileSync(
+      join(home, 'fleet', 'roster.yaml'),
+      [
+        'version: 1',
+        'agents:',
+        '  - name: orchestrator',
+        '    runtime: pi',
+        '  - name: coder0',
+        '    runtime: claude',
+        '  - name: "reviewer-1"',
+        '    runtime: codex',
+      ].join('\n') + '\n',
+    );
+    expect(readRosterAgentNames(home)).toEqual(['orchestrator', 'coder0', 'reviewer-1']);
+  });
+});
+
+describe('runFrameworkReseed', () => {
+  it('reports not-ok (not throw) when the installer is absent', () => {
+    const missing = mkdtempSync(join(tmpdir(), 'mosaic-noinstaller-'));
+    const res = runFrameworkReseed(missing, join(missing, 'home'));
+    expect(res.ok).toBe(false);
+    expect(res.reason).toContain('installer not found');
+    rmSync(missing, { recursive: true, force: true });
+  });
+});

packages/mosaic/src/runtime/update-checker.ts

@@ -16,7 +16,8 @@
 import { execSync } from 'node:child_process';
 import { existsSync, mkdirSync, readFileSync, writeFileSync } from 'node:fs';
 import { homedir } from 'node:os';
-import { join } from 'node:path';
+import { dirname, join, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
 
 // ─── Types ──────────────────────────────────────────────────────────────────
 
@@ -453,6 +454,98 @@ export function getInstallAllCommand(outdated: PackageUpdateResult[]): string {
   return `npm i -g ${pkgs.join(' ')}`;
 }
 
+// ─── Post-update framework re-seed + agent relaunch (F3-m3 / R13) ─────────────
+//
+// `mosaic update` installs the new npm CLI but, on its own, leaves the framework
+// files in ~/.config/mosaic/ stale — so shipped launcher/runtime changes (e.g.
+// the agent-name export + native heartbeat) never ACTIVATE until a re-seed.
+// These helpers run the package's own install.sh in sync-only mode (the P4
+// data-safe reconcile: framework-owned overwrite + backup-once; SOUL/USER/
+// *.local/credentials preserved) and, opt-in, relaunch durable agents.
+
+/** Resolve the framework/ directory bundled in the installed package. */
+export function resolveBundledFrameworkRoot(): string {
+  // dist/runtime/update-checker.js → ../../framework (package files: dist + framework)
+  return resolve(dirname(fileURLToPath(import.meta.url)), '..', '..', 'framework');
+}
+
+export const FRAMEWORK_RESEED_PACKAGE = PKG;
+
+/**
+ * Build the framework re-seed invocation: the package's install.sh in
+ * sync-only mode (file phase only — no environment-touching post-install),
+ * keep mode (never overwrite user files). Returned as data so it is unit
+ * testable; `runFrameworkReseed` executes it.
+ */
+export function buildReseedCommand(
+  frameworkRoot: string,
+  mosaicHome: string,
+): { installer: string; command: string; env: Record<string, string> } {
+  const installer = join(frameworkRoot, 'install.sh');
+  return {
+    installer,
+    command: `bash ${installer}`,
+    env: {
+      MOSAIC_SYNC_ONLY: '1',
+      MOSAIC_INSTALL_MODE: 'keep',
+      MOSAIC_HOME: mosaicHome,
+    },
+  };
+}
+
+/**
+ * Re-seed the framework from the freshly-installed package. Returns a result
+ * describing what happened (so callers can message + decide on relaunch).
+ * Best-effort: a missing installer or a non-zero exit is reported, not thrown.
+ */
+export function runFrameworkReseed(
+  frameworkRoot = resolveBundledFrameworkRoot(),
+  mosaicHome = join(homedir(), '.config', 'mosaic'),
+): { ok: boolean; reason?: string } {
+  const { installer, command, env } = buildReseedCommand(frameworkRoot, mosaicHome);
+  if (!existsSync(installer)) {
+    return { ok: false, reason: `installer not found: ${installer}` };
+  }
+  try {
+    execSync(command, { stdio: 'inherit', env: { ...process.env, ...env }, timeout: 120_000 });
+    return { ok: true };
+  } catch (err) {
+    return { ok: false, reason: err instanceof Error ? err.message : String(err) };
+  }
+}
+
+/**
+ * Best-effort parse of the fleet roster for agent names (used to relaunch
+ * durable agents after a re-seed). Returns [] when no roster exists.
+ */
+export function readRosterAgentNames(mosaicHome = join(homedir(), '.config', 'mosaic')): string[] {
+  const rosterPath = join(mosaicHome, 'fleet', 'roster.yaml');
+  if (!existsSync(rosterPath)) return [];
+  let text: string;
+  try {
+    text = readFileSync(rosterPath, 'utf-8');
+  } catch {
+    return [];
+  }
+  // Roster agents are listed as `- name: <id>` entries under `agents:`.
+  const names: string[] = [];
+  for (const line of text.split('\n')) {
+    const m = line.match(/^\s*-?\s*name:\s*["']?([A-Za-z0-9._-]+)["']?\s*$/);
+    if (m && m[1]) names.push(m[1]);
+  }
+  return names;
+}
+
+/** Build the per-agent systemd relaunch commands (drain+relaunch via restart). */
+export function buildRelaunchCommands(agentNames: string[]): string[][] {
+  return agentNames.map((name) => [
+    'systemctl',
+    '--user',
+    'restart',
+    `mosaic-agent@${name}.service`,
+  ]);
+}
+
 /**
  * Format a table showing all packages with their current/latest versions.
  */