webby: Case 2 design r10 review (#416), changes B1-B3, and session line

agents/webby/work/case2-r10/REVIEW.md

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+# Webby review: Case 2 design r10 (#416), two system units
+
+Webby, 2026-10-20T21:01Z (from `date -u`). Author: Gosalyn (gosalyn-0045). Commit 4281b0064 on
+gosalyn/case2-design, DESIGN blob 4a1860e698e0. Diff `git diff 51006710a 4281b0064`, one commit. I
+read both unit templates, scripts/webui-service.sh, webui `cli.mjs serve`, scripts/mosaic and decisions 62,
+94 and 102 on origin/refactor. Static review.
+
+## Verdict: CHANGES (B1, B2, B3)
+
+The fix is the right one. Two units from the existing templates match how the stack runs today, and C2-10b
+needs the Console. One copy for both units keeps the human proof working, since the bus accepts only its
+own human-cli.mjs path (webui-service.sh:266-273). Making `%h` literal is correct for a system unit. The new
+refusal cases are good.
+
+B1. The Console's boot start is Jason's call, not mine or Mos's, and the design should default to the strict
+reading until he rules. Decision 94 (lead-decisions:2016-2023) says the process that starts the Console
+holds human authority, and that a start through systemd gives a clean ancestry the proof accepts, "the
+detachment gap decision 62 names". Decision 102 lets one named seat, Mos, start it. It calls that a
+tradeoff Jason accepted, because "the human proof now rests on Jason's grant to one named seat" (:2253). A
+boot-enabled system unit hands that start to PID 1 on every reboot, with no named starter. That extends a
+human-authority boundary, so under AGENTS.md it needs an owner decision. Decision 94 also accepts the
+local-forgery limit only "for this PoC on dragon-lin under Jason's user ... this decision doesn't carry the
+limit there" (:2058-2062). On .54 any process that reaches the Console port can send as Melanie, and
+`melanie`'s Hermes processes and sudo are on that host until #423 step 5. Nobody has accepted that limit
+for .54.
+
+Fix: render the Console unit with no `[Install]` section, so a human or Mos starts it at step 9 and after
+each boot. That fails closed and is cheap to reverse, because adding `[Install]` later is one re-render.
+Put two questions to Jason through Mos: may a boot start stand in for the human's start on .54, and does he
+accept the local-forgery limit there? The bus unit can stay boot-enabled, since it holds no human
+capability.
+
+B2. `@PATH@`, `@NODE@` and `@FLAGS@` have no render rule. Both templates set
+`Environment=PATH=@PATH@` (mosaic-bus.service.in:15, mosaic-webui.service.in:25). The bus `ExecStart` is
+scripts/mosaic, a bash script that runs `exec node` from PATH (scripts/mosaic:22-40). So the bus's node is
+whatever PATH the render writes, not `--node`. Row 195 found v22 on .53, and the precheck checks
+`node --version` on `<user>`'s shell PATH, not the unit's. Fix: say `@PATH@` is `dirname(--node)` followed
+by `/usr/local/bin:/usr/bin:/bin`, as webui-service.sh:246-248 does, and `@NODE@` is `--node`. Say
+`@FLAGS@` is the checked serve flags, and refuse any `@[A-Z_]+@` left in either render, not only `%h`. Add
+a test that the bus unit's PATH starts with the `--node` directory.
+
+B3. The hardening lines are never listed. In r9 they lived in the new template that C2-13 owned. r10 drops
+that template, and the render "adds ... the hardening lines", but neither the design nor the brief says
+which ones. The test "a template with a hardening line removed" has nothing to remove: the templates carry
+only `NoNewPrivileges=yes`. Some common lines break sessions. `RestrictNamespaces=`, `PrivateUsers=` or a
+`SystemCallFilter=` without the namespace calls stops bwrap, and then no role starts. The bwrap precheck
+runs in `<user>`'s shell, outside the unit's sandbox, so it can't catch that. Fix: list the exact lines in
+the brief (for example `ProtectHome=yes`, `ProtectSystem=strict` with `ReadWritePaths=<home>`,
+`PrivateTmp=yes`, `NoNewPrivileges=yes`), say none of them restricts user namespaces, and add a step 9
+check that one session starts under the bus unit.
+
+## Non-blocking
+
+N1. Both templates already end with `[Install]` `WantedBy=default.target` (bus :41-42, webui :39-40). The
+render should replace that line with `multi-user.target`, not add a second one. Under B1 it removes the
+Console's section.
+
+N2. The render adds no `After=` or `Wants=`, so at boot the two units start in parallel. That is harmless
+today, because serve calls the bus per request (webui cli.mjs, `busCaller`) and starts without it. But the
+stated order applies only to a manual step 9. Either add `After=mosaic-bus@<business>.service` to the
+Console unit, or say that boot order doesn't matter.
+
+N3. "The serve flags pass scripts/webui-service.sh's own flag checks" can't be done by calling that
+script. `serve_flags` (:146-207) is internal. Its proof-file check compares the owner to `id -u` (:201),
+which is root under case2-unit.sh. `render` finds node with `command -v` (:237), not `--node`. And
+webui-service.sh isn't in the files owned. Say whether case2-unit.sh copies the checks, with tests, or
+whether the row may move `serve_flags` into a sourced file. Also state which serve flags Case 2 uses.
+
+N4. With a copy, webui-service.sh passes `--checkout <canonical>` (:251). Her host has no canonical
+checkout, so the queue read runs from the copy, and the queue store refuses that. Say that the Console unit
+gets no `--checkout`, and that the queue panel isn't part of Case 2.
+
+N5. A re-pin must move both units to the same copy, or the human proof fails (webui-service.sh:266-273).
+Have case2-unit.sh refuse a render whose two units name different copy ids, and test it.

docs/SESSIONS.md

@@ -1390,3 +1390,4 @@ are never rewritten or removed; corrections are new entries.
 2026-10-20T20:49Z | Webby (Opus 5.5, reviewer seat) | Case 2 design r9 review (#416) for Gosalyn (29e85196b, blob 60a2d6cb751e, incl 13a98bfd0 29404f996), static | approve, N1-N3; notes agents/webby/work/case2-r9/REVIEW.md
 2026-10-20T20:50Z | Webby (Opus 5.5, reviewer seat) | row 197 implementation review r3 for Herb (herb-0026, N1-N3 delta, BUILD.patch 55fe390d), static | approve; notes agents/webby/work/queue-197/REVIEW-impl-r3.md
 2026-10-20T20:55Z | Webby (Opus 5.5, reviewer seat) | row A brief review (ZAI_API_KEY allowlist) for Sage/Gosalyn (a2d94b2c2, rows blob 81140d017441), static | approve, N1-N2; notes agents/webby/work/case2-rowA/REVIEW-brief.md
+2026-10-20T21:01Z | Webby (Opus 5.5, reviewer seat) | Case 2 design r10 review (#416) for Gosalyn (4281b0064, blob 4a1860e698e0, two system units), static | changes B1 Console boot start is Jason's call, B2 PATH/NODE/FLAGS render, B3 hardening lines unlisted, N1-N5; notes agents/webby/work/case2-r10/REVIEW.md