feat: add multi-runtime support (coord run, prdy --codex) and next-task capsule

- coord/prdy subcommands now accept --claude/--codex runtime flags
- New `mosaic coord run` generates continuation context and launches
  selected runtime, replacing manual copy/paste workflow
- Next-task capsule (.mosaic/orchestrator/next-task.json) provides
  machine-readable execution context for deterministic session launches
- Codex strict orchestrator profile added to runtime/codex/RUNTIME.md
- Orchestrator protocol updated with between-session run flow
- New smoke-test.sh for orchestration behavior verification

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bin/mosaic

@@ -53,8 +53,8 @@ Management:
 
 PRD:
   prdy <subcommand>      PRD creation and validation
-                         init    Create docs/PRD.md via Claude session
+                         init    Create docs/PRD.md via guided runtime session
-                         update  Update existing PRD via Claude session
+                         update  Update existing PRD via guided runtime session
                          validate Check PRD completeness (bash-only)
 
 Coordinator (r0):
@@ -63,6 +63,7 @@ Coordinator (r0):
                          mission Show mission progress dashboard
                          status  Check agent session health
                          continue Generate continuation prompt
+                         run     Generate context and launch selected runtime
                          resume  Crash recovery
 
 Options:
@@ -481,26 +482,59 @@ run_seq() {
 
 run_coord() {
   check_mosaic_home
-  local subcmd="${1:-help}"
+  local runtime="claude"
-  shift || true
+  local runtime_flag=""
+  local -a coord_args=()
+
+  while [[ $# -gt 0 ]]; do
+    case "$1" in
+      --claude|--codex)
+        local selected_runtime="${1#--}"
+        if [[ -n "$runtime_flag" ]] && [[ "$runtime" != "$selected_runtime" ]]; then
+          echo "[mosaic] ERROR: --claude and --codex are mutually exclusive for 'mosaic coord'." >&2
+          exit 1
+        fi
+        runtime="$selected_runtime"
+        runtime_flag="$1"
+        shift
+        ;;
+      *)
+        coord_args+=("$1")
+        shift
+        ;;
+    esac
+  done
+
+  local subcmd="${coord_args[0]:-help}"
+  if (( ${#coord_args[@]} > 1 )); then
+    set -- "${coord_args[@]:1}"
+  else
+    set --
+  fi
 
   local tool_dir="$MOSAIC_HOME/tools/orchestrator"
 
   case "$subcmd" in
     status|session)
-      exec bash "$tool_dir/session-status.sh" "$@"
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/session-status.sh" "$@"
       ;;
     init)
-      exec bash "$tool_dir/mission-init.sh" "$@"
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/mission-init.sh" "$@"
       ;;
     mission|progress)
-      exec bash "$tool_dir/mission-status.sh" "$@"
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/mission-status.sh" "$@"
       ;;
     continue|next)
-      exec bash "$tool_dir/continue-prompt.sh" "$@"
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/continue-prompt.sh" "$@"
+      ;;
+    run|start)
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/session-run.sh" "$@"
+      ;;
+    smoke|test)
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/smoke-test.sh" "$@"
       ;;
     resume|recover)
-      exec bash "$tool_dir/session-resume.sh" "$@"
+      MOSAIC_COORD_RUNTIME="$runtime" exec bash "$tool_dir/session-resume.sh" "$@"
       ;;
     help|*)
       cat <<COORD_USAGE
@@ -511,12 +545,23 @@ Commands:
   mission [--project <path>]  Show mission progress dashboard
   status [--project <path>]   Check agent session health
   continue [--project <path>] Generate continuation prompt for next session
+  run [--project <path>]      Generate context and launch selected runtime
+  smoke                       Run orchestration behavior smoke checks
   resume [--project <path>]   Crash recovery (detect dirty state, generate fix)
 
+Runtime:
+  --claude                    Use Claude runtime hints/prompts (default)
+  --codex                     Use Codex runtime hints/prompts
+
 Examples:
   mosaic coord init --name "Security Fix" --milestones "Critical,High,Medium"
   mosaic coord mission
+  mosaic coord --codex mission
   mosaic coord continue --copy
+  mosaic coord run
+  mosaic coord run --codex
+  mosaic coord smoke
+  mosaic coord continue --codex --copy
 
 COORD_USAGE
       ;;
@@ -552,33 +597,65 @@ _check_resumable_session() {
 
 run_prdy() {
   check_mosaic_home
-  local subcmd="${1:-help}"
+  local runtime="claude"
-  shift || true
+  local runtime_flag=""
+  local -a prdy_args=()
+
+  while [[ $# -gt 0 ]]; do
+    case "$1" in
+      --claude|--codex)
+        local selected_runtime="${1#--}"
+        if [[ -n "$runtime_flag" ]] && [[ "$runtime" != "$selected_runtime" ]]; then
+          echo "[mosaic] ERROR: --claude and --codex are mutually exclusive for 'mosaic prdy'." >&2
+          exit 1
+        fi
+        runtime="$selected_runtime"
+        runtime_flag="$1"
+        shift
+        ;;
+      *)
+        prdy_args+=("$1")
+        shift
+        ;;
+    esac
+  done
+
+  local subcmd="${prdy_args[0]:-help}"
+  if (( ${#prdy_args[@]} > 1 )); then
+    set -- "${prdy_args[@]:1}"
+  else
+    set --
+  fi
 
   local tool_dir="$MOSAIC_HOME/tools/prdy"
 
   case "$subcmd" in
     init)
-      exec bash "$tool_dir/prdy-init.sh" "$@"
+      MOSAIC_PRDY_RUNTIME="$runtime" exec bash "$tool_dir/prdy-init.sh" "$@"
       ;;
     update)
-      exec bash "$tool_dir/prdy-update.sh" "$@"
+      MOSAIC_PRDY_RUNTIME="$runtime" exec bash "$tool_dir/prdy-update.sh" "$@"
       ;;
     validate|check)
-      exec bash "$tool_dir/prdy-validate.sh" "$@"
+      MOSAIC_PRDY_RUNTIME="$runtime" exec bash "$tool_dir/prdy-validate.sh" "$@"
       ;;
     help|*)
       cat <<PRDY_USAGE
 mosaic prdy — PRD creation and validation tools
 
 Commands:
-  init [--project <path>] [--name <feature>]   Create docs/PRD.md via guided Claude session
+  init [--project <path>] [--name <feature>]   Create docs/PRD.md via guided runtime session
-  update [--project <path>]                    Update existing docs/PRD.md via Claude session
+  update [--project <path>]                    Update existing docs/PRD.md via guided runtime session
   validate [--project <path>]                  Check PRD completeness against Mosaic guide (bash-only)
 
+Runtime:
+  --claude                    Use Claude runtime (default)
+  --codex                     Use Codex runtime
+
 Examples:
   mosaic prdy init --name "User Authentication"
   mosaic prdy update
+  mosaic prdy --codex init --name "User Authentication"
   mosaic prdy validate
 
 Output location: docs/PRD.md (per Mosaic PRD guide)

guides/ORCHESTRATOR-PROTOCOL.md

@@ -131,9 +131,9 @@ If context usage is high, produce a handoff message:
 4. Commit all state files
 5. The coordinator will generate a continuation prompt for the next session
 
-### Continuation Prompt Format
+### Continuation Prompt and Capsule Format
 
-The coordinator generates this (via `mosaic coord continue`):
+The coordinator generates this (via `mosaic coord continue`) and writes a machine-readable capsule at `.mosaic/orchestrator/next-task.json`:
 
 ```
 ## Continuation Mission
@@ -152,6 +152,16 @@ Continue **{mission}** from existing state.
 4. Human launches new session and pastes the prompt
 5. New agent reads manifest, scratchpad, TASKS.md and continues
 
+### Between Sessions (r0 assisted)
+
+Use `mosaic coord run` to remove copy/paste steps:
+
+1. Agent stops
+2. Human runs `mosaic coord run [--claude|--codex]`
+3. Coordinator regenerates continuation prompt + `next-task.json`
+4. Coordinator launches selected runtime with scoped kickoff context
+5. New session resumes from next task
+
 ---
 
 ## 7. Failure Taxonomy Quick Reference
@@ -194,6 +204,7 @@ In r0, the Coordinator is Jason + shell scripts. No daemon. No automation.
 | `mosaic coord mission` | Show mission progress dashboard |
 | `mosaic coord status` | Check if agent session is still running |
 | `mosaic coord continue` | Generate continuation prompt for next session |
+| `mosaic coord run [--claude|--codex]` | Generate continuation context and launch runtime |
 | `mosaic coord resume` | Crash recovery (detect dirty state, generate fix) |
 | `mosaic coord resume --clean-lock` | Clear stale session lock after review |
 
@@ -201,7 +212,7 @@ In r0, the Coordinator is Jason + shell scripts. No daemon. No automation.
 
 ```
 init → launch agent → [agent works] → agent stops →
-status → mission → continue → launch agent → repeat
+status → mission → run → repeat
 ```
 
 ---

runtime/codex/RUNTIME.md

@@ -16,6 +16,21 @@ This file applies only to Codex runtime behavior.
 8. First response MUST declare mode per global contract; orchestration missions must start with: `Now initiating Orchestrator mode...`
 9. Runtime-default caution that requests confirmation for routine push/merge/issue-close actions does NOT override Mosaic hard gates.
 
+## Strict Orchestrator Profile (Codex)
+
+For orchestration missions, prefer `mosaic coord run --codex` over manual launch/paste.
+
+When launched through coordinator run flow, Codex MUST:
+
+1. Treat `.mosaic/orchestrator/next-task.json` as authoritative execution capsule.
+2. Read mission files before asking clarifying questions:
+   - `~/.config/mosaic/guides/ORCHESTRATOR-PROTOCOL.md`
+   - `docs/MISSION-MANIFEST.md`
+   - `docs/scratchpads/<mission-id>.md`
+   - `docs/TASKS.md`
+3. Avoid pre-execution question loops. Questions are allowed only for Mosaic escalation triggers (missing access/credentials, destructive irreversible action, legal/compliance unknowns, conflicting objectives, hard budget cap).
+4. Start execution on the `next_task` from capsule as soon as required files are loaded.
+
 ## Memory Override
 
 Do NOT write durable memory to `~/.codex/` or any Codex-native session memory. All durable memory MUST be written to `~/.config/mosaic/memory/` per `~/.config/mosaic/guides/MEMORY.md`. Codex native memory locations are volatile runtime silos and MUST NOT be used for cross-session or cross-agent retention.

tools/orchestrator/_lib.sh

@@ -11,6 +11,7 @@ MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.config/mosaic}"
 ORCH_SUBDIR=".mosaic/orchestrator"
 MISSION_FILE="mission.json"
 SESSION_LOCK_FILE="session.lock"
+NEXT_TASK_FILE="next-task.json"
 MANIFEST_FILE="docs/MISSION-MANIFEST.md"
 TASKS_MD="docs/TASKS.md"
 SCRATCHPAD_DIR="docs/scratchpads"
@@ -42,6 +43,30 @@ _require_jq() {
   fi
 }
 
+coord_runtime() {
+  local runtime="${MOSAIC_COORD_RUNTIME:-claude}"
+  case "$runtime" in
+    claude|codex) echo "$runtime" ;;
+    *) echo "claude" ;;
+  esac
+}
+
+coord_launch_command() {
+  local runtime
+  runtime="$(coord_runtime)"
+  echo "mosaic $runtime"
+}
+
+coord_run_command() {
+  local runtime
+  runtime="$(coord_runtime)"
+  if [[ "$runtime" == "claude" ]]; then
+    echo "mosaic coord run"
+  else
+    echo "mosaic coord run --$runtime"
+  fi
+}
+
 # ─── Project / state file access ────────────────────────────────────────────
 
 # Return the orchestrator directory for a project
@@ -56,6 +81,11 @@ mission_path() {
   echo "$(orch_dir "$project")/$MISSION_FILE"
 }
 
+next_task_capsule_path() {
+  local project="${1:-.}"
+  echo "$(orch_dir "$project")/$NEXT_TASK_FILE"
+}
+
 # Exit with error if mission.json is missing or inactive
 require_mission() {
   local project="${1:-.}"
@@ -358,6 +388,113 @@ milestone_name() {
   jq -r --arg id "$mid" '.milestones[] | select(.id == $id) | .name // empty' "$mp"
 }
 
+# ─── Next-task capsule helpers ───────────────────────────────────────────────
+
+write_next_task_capsule() {
+  local project="${1:-.}"
+  local runtime="${2:-claude}"
+  local mission_id="${3:-}"
+  local mission_name="${4:-}"
+  local project_path="${5:-}"
+  local quality_gates="${6:-}"
+  local current_ms_id="${7:-}"
+  local current_ms_name="${8:-}"
+  local next_task="${9:-}"
+  local tasks_done="${10:-0}"
+  local tasks_total="${11:-0}"
+  local pct="${12:-0}"
+  local current_branch="${13:-}"
+
+  _require_jq || return 1
+  mkdir -p "$(orch_dir "$project")"
+
+  local payload
+  payload="$(jq -n \
+    --arg generated_at "$(iso_now)" \
+    --arg runtime "$runtime" \
+    --arg mission_id "$mission_id" \
+    --arg mission_name "$mission_name" \
+    --arg project_path "$project_path" \
+    --arg quality_gates "$quality_gates" \
+    --arg current_ms_id "$current_ms_id" \
+    --arg current_ms_name "$current_ms_name" \
+    --arg next_task "$next_task" \
+    --arg current_branch "$current_branch" \
+    --arg tasks_done "$tasks_done" \
+    --arg tasks_total "$tasks_total" \
+    --arg pct "$pct" \
+    '{
+      generated_at: $generated_at,
+      runtime: $runtime,
+      mission_id: $mission_id,
+      mission_name: $mission_name,
+      project_path: $project_path,
+      quality_gates: $quality_gates,
+      current_milestone: {
+        id: $current_ms_id,
+        name: $current_ms_name
+      },
+      next_task: $next_task,
+      progress: {
+        tasks_done: ($tasks_done | tonumber),
+        tasks_total: ($tasks_total | tonumber),
+        pct: ($pct | tonumber)
+      },
+      current_branch: $current_branch
+    }')"
+
+  write_json "$(next_task_capsule_path "$project")" "$payload"
+}
+
+build_codex_strict_kickoff() {
+  local project="${1:-.}"
+  local continuation_prompt="${2:-}"
+
+  _require_jq || return 1
+
+  local capsule_path
+  capsule_path="$(next_task_capsule_path "$project")"
+  local capsule='{}'
+  if [[ -f "$capsule_path" ]]; then
+    capsule="$(cat "$capsule_path")"
+  fi
+
+  local mission_id next_task project_path quality_gates
+  mission_id="$(echo "$capsule" | jq -r '.mission_id // "unknown"')"
+  next_task="$(echo "$capsule" | jq -r '.next_task // "none"')"
+  project_path="$(echo "$capsule" | jq -r '.project_path // "."')"
+  quality_gates="$(echo "$capsule" | jq -r '.quality_gates // "none"')"
+
+  cat <<EOF
+Now initiating Orchestrator mode...
+
+STRICT EXECUTION PROFILE FOR CODEX (HARD GATE)
+- Do NOT ask clarifying questions before your first tool actions unless a Mosaic escalation trigger is hit.
+- Your first actions must be reading mission state files in order.
+- Treat the next-task capsule as authoritative execution input.
+
+REQUIRED FIRST ACTIONS (IN ORDER)
+1. Read ~/.config/mosaic/guides/ORCHESTRATOR-PROTOCOL.md
+2. Read docs/MISSION-MANIFEST.md
+3. Read docs/scratchpads/${mission_id}.md
+4. Read docs/TASKS.md
+5. Begin execution on next task: ${next_task}
+
+WORKING CONTEXT
+- Project: ${project_path}
+- Quality gates: ${quality_gates}
+- Capsule file: .mosaic/orchestrator/next-task.json
+
+Task capsule (JSON):
+\`\`\`json
+${capsule}
+\`\`\`
+
+Continuation prompt:
+${continuation_prompt}
+EOF
+}
+
 # Get next milestone after the given one
 next_milestone_id() {
   local project="${1:-.}"

tools/orchestrator/continue-prompt.sh

@@ -30,6 +30,8 @@ done
 
 _require_jq
 require_mission "$PROJECT"
+target_runtime="$(coord_runtime)"
+launch_cmd="$(coord_launch_command)"
 
 # ─── Load mission data ──────────────────────────────────────────────────────
 
@@ -93,6 +95,22 @@ if (( session_count > 0 )); then
   fi
 fi
 
+# Write machine-readable next-task capsule for deterministic runtime launches.
+write_next_task_capsule \
+  "$PROJECT" \
+  "$target_runtime" \
+  "$mission_id" \
+  "$mission_name" \
+  "$project_path" \
+  "$quality_gates" \
+  "$current_ms_id" \
+  "$current_ms_name" \
+  "$next_task" \
+  "$tasks_done" \
+  "$tasks_total" \
+  "$pct" \
+  "$current_branch"
+
 # ─── Generate prompt ────────────────────────────────────────────────────────
 
 prompt="$(cat <<EOF
@@ -108,6 +126,7 @@ Continue **$mission_name** from existing state.
 - **Scratchpad:** docs/scratchpads/${mission_id}.md
 - **Protocol:** ~/.config/mosaic/guides/ORCHESTRATOR.md
 - **Quality gates:** $quality_gates
+- **Target runtime:** $target_runtime
 
 ## Resume Point
 
@@ -129,9 +148,10 @@ Continue **$mission_name** from existing state.
 3. Read \`docs/scratchpads/${mission_id}.md\` for session history and decisions
 4. Read \`docs/TASKS.md\` for current task state
 5. \`git pull --rebase\` to sync latest changes
-6. Continue execution from task **${next_task:-next-pending}**
+6. Launch runtime with \`$launch_cmd\`
-7. Follow Two-Phase Completion Protocol
+7. Continue execution from task **${next_task:-next-pending}**
-8. You are the SOLE writer of \`docs/TASKS.md\`
+8. Follow Two-Phase Completion Protocol
+9. You are the SOLE writer of \`docs/TASKS.md\`
 EOF
 )"
 

tools/orchestrator/mission-init.sh

@@ -270,6 +270,9 @@ fi
 
 # ─── Report ──────────────────────────────────────────────────────────────────
 
+runtime_cmd="$(coord_launch_command)"
+run_cmd="$(coord_run_command)"
+
 echo ""
 echo -e "${C_GREEN}${C_BOLD}Mission initialized: $NAME${C_RESET}"
 echo ""
@@ -280,4 +283,4 @@ echo -e "  ${C_CYAN}Manifest:${C_RESET}    $manifest_path"
 echo -e "  ${C_CYAN}Scratchpad:${C_RESET}  $sp_file"
 echo -e "  ${C_CYAN}Tasks:${C_RESET}       $tasks_path"
 echo ""
-echo "Next: Launch an agent session with 'mosaic claude' or generate a prompt with 'mosaic coord continue'"
+echo "Next: Resume with '$run_cmd' (or launch directly with '$runtime_cmd')."

tools/orchestrator/session-run.sh

@@ -0,0 +1,80 @@
+#!/usr/bin/env bash
+set -euo pipefail
+#
+# session-run.sh — Generate continuation context and launch target runtime.
+#
+# Usage:
+#   session-run.sh [--project <path>] [--milestone <id>] [--print]
+#
+# Behavior:
+# - Builds continuation prompt + next-task capsule.
+# - Launches selected runtime (default: claude, override via MOSAIC_COORD_RUNTIME).
+# - For codex, injects strict orchestration kickoff to reduce clarification loops.
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/_lib.sh"
+
+PROJECT="."
+MILESTONE=""
+PRINT=false
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --project)   PROJECT="$2"; shift 2 ;;
+    --milestone) MILESTONE="$2"; shift 2 ;;
+    --print)     PRINT=true; shift ;;
+    -h|--help)
+      cat <<'USAGE'
+Usage: session-run.sh [--project <path>] [--milestone <id>] [--print]
+
+Options:
+  --project <path>   Project directory (default: CWD)
+  --milestone <id>   Force specific milestone context
+  --print            Print launch prompt only (no runtime launch)
+USAGE
+      exit 0
+      ;;
+    *) echo "Unknown option: $1" >&2; exit 1 ;;
+  esac
+done
+
+PROJECT="${PROJECT/#\~/$HOME}"
+PROJECT="$(cd "$PROJECT" && pwd)"
+
+_require_jq
+require_mission "$PROJECT"
+
+runtime="$(coord_runtime)"
+launch_cmd="$(coord_launch_command)"
+
+continue_cmd=(bash "$SCRIPT_DIR/continue-prompt.sh" --project "$PROJECT")
+if [[ -n "$MILESTONE" ]]; then
+  continue_cmd+=(--milestone "$MILESTONE")
+fi
+
+continuation_prompt="$(MOSAIC_COORD_RUNTIME="$runtime" "${continue_cmd[@]}")"
+
+if [[ "$runtime" == "codex" ]]; then
+  launch_prompt="$(build_codex_strict_kickoff "$PROJECT" "$continuation_prompt")"
+else
+  launch_prompt="$continuation_prompt"
+fi
+
+if [[ "$PRINT" == true ]]; then
+  echo "$launch_prompt"
+  exit 0
+fi
+
+echo -e "${C_CYAN}Launching orchestration runtime: ${launch_cmd}${C_RESET}"
+echo -e "${C_CYAN}Project:${C_RESET} $PROJECT"
+echo -e "${C_CYAN}Capsule:${C_RESET} $(next_task_capsule_path "$PROJECT")"
+
+cd "$PROJECT"
+if [[ "$runtime" == "claude" ]]; then
+  exec "$MOSAIC_HOME/bin/mosaic" claude "$launch_prompt"
+elif [[ "$runtime" == "codex" ]]; then
+  exec "$MOSAIC_HOME/bin/mosaic" codex "$launch_prompt"
+fi
+
+echo -e "${C_RED}Unsupported coord runtime: $runtime${C_RESET}" >&2
+exit 1

tools/orchestrator/session-status.sh

@@ -33,6 +33,8 @@ while [[ $# -gt 0 ]]; do
 done
 
 _require_jq
+runtime_cmd="$(coord_launch_command)"
+run_cmd="$(coord_run_command)"
 
 # ─── Check session lock ─────────────────────────────────────────────────────
 
@@ -103,8 +105,9 @@ if ! lock_data="$(session_lock_read "$PROJECT")"; then
 
       if [[ "$m_status" == "active" || "$m_status" == "paused" ]]; then
         echo -e "  ${C_BOLD}Next steps:${C_RESET}"
+        echo "    $run_cmd                 Auto-generate context and launch"
         echo "    mosaic coord continue     Generate continuation prompt"
-        echo "    mosaic yolo claude        Launch agent session"
+        echo "    $runtime_cmd              Launch agent session"
       elif [[ "$m_status" == "completed" ]]; then
         echo -e "  ${C_DIM}Mission completed. Start a new one with: mosaic coord init${C_RESET}"
       else

tools/orchestrator/smoke-test.sh

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+set -euo pipefail
+#
+# smoke-test.sh — Behavior smoke checks for coord continue/run workflows.
+#
+# Usage:
+#   smoke-test.sh
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/_lib.sh"
+
+PASS=0
+FAIL=0
+
+pass_case() {
+  echo "PASS: $1"
+  PASS=$((PASS + 1))
+}
+
+fail_case() {
+  echo "FAIL: $1" >&2
+  FAIL=$((FAIL + 1))
+}
+
+tmp_project="$(mktemp -d)"
+trap 'rm -rf "$tmp_project"' EXIT
+
+mkdir -p "$tmp_project/.mosaic/orchestrator" "$tmp_project/docs/scratchpads"
+
+cat > "$tmp_project/.mosaic/orchestrator/mission.json" <<'JSON'
+{
+  "mission_id": "smoke-mission-20260223",
+  "name": "Smoke Mission",
+  "status": "active",
+  "project_path": "SMOKE_PROJECT",
+  "quality_gates": "pnpm lint && pnpm test",
+  "milestones": [
+    { "id": "M1", "name": "Milestone One", "status": "pending" }
+  ],
+  "sessions": []
+}
+JSON
+
+cat > "$tmp_project/docs/MISSION-MANIFEST.md" <<'MD'
+# Mission Manifest
+MD
+
+cat > "$tmp_project/docs/scratchpads/smoke-mission-20260223.md" <<'MD'
+# Scratchpad
+MD
+
+cat > "$tmp_project/docs/TASKS.md" <<'MD'
+| id | status | milestone | description | pr | notes |
+|----|--------|-----------|-------------|----|-------|
+| T-001 | pending | M1 | Smoke task | | |
+MD
+
+codex_continue_output="$(MOSAIC_COORD_RUNTIME=codex bash "$SCRIPT_DIR/continue-prompt.sh" --project "$tmp_project")"
+capsule_file="$tmp_project/.mosaic/orchestrator/next-task.json"
+
+if [[ -f "$capsule_file" ]]; then pass_case "continue writes next-task capsule"; else fail_case "continue writes next-task capsule"; fi
+if jq -e '.runtime == "codex"' "$capsule_file" >/dev/null 2>&1; then pass_case "capsule runtime is codex"; else fail_case "capsule runtime is codex"; fi
+if jq -e '.next_task == "T-001"' "$capsule_file" >/dev/null 2>&1; then pass_case "capsule next_task is T-001"; else fail_case "capsule next_task is T-001"; fi
+if grep -Fq 'Target runtime:** codex' <<< "$codex_continue_output"; then pass_case "continue prompt contains target runtime codex"; else fail_case "continue prompt contains target runtime codex"; fi
+
+codex_run_prompt="$(MOSAIC_COORD_RUNTIME=codex bash "$SCRIPT_DIR/session-run.sh" --project "$tmp_project" --print)"
+if [[ "$(printf '%s\n' "$codex_run_prompt" | head -n1)" == "Now initiating Orchestrator mode..." ]]; then pass_case "codex run prompt first line is mode declaration"; else fail_case "codex run prompt first line is mode declaration"; fi
+if grep -Fq 'Do NOT ask clarifying questions before your first tool actions' <<< "$codex_run_prompt"; then pass_case "codex run prompt includes no-questions hard gate"; else fail_case "codex run prompt includes no-questions hard gate"; fi
+if grep -Fq '"next_task": "T-001"' <<< "$codex_run_prompt"; then pass_case "codex run prompt embeds capsule json"; else fail_case "codex run prompt embeds capsule json"; fi
+
+claude_run_prompt="$(MOSAIC_COORD_RUNTIME=claude bash "$SCRIPT_DIR/session-run.sh" --project "$tmp_project" --print)"
+if [[ "$(printf '%s\n' "$claude_run_prompt" | head -n1)" == "## Continuation Mission" ]]; then pass_case "claude run prompt remains continuation prompt format"; else fail_case "claude run prompt remains continuation prompt format"; fi
+
+echo ""
+echo "Smoke test summary: pass=$PASS fail=$FAIL"
+if (( FAIL > 0 )); then
+  exit 1
+fi

tools/prdy/_lib.sh

@@ -41,6 +41,20 @@ _require_cmd() {
   fi
 }
 
+prdy_runtime() {
+  local runtime="${MOSAIC_PRDY_RUNTIME:-claude}"
+  case "$runtime" in
+    claude|codex) echo "$runtime" ;;
+    *) echo "claude" ;;
+  esac
+}
+
+prdy_runtime_command() {
+  local runtime
+  runtime="$(prdy_runtime)"
+  echo "$runtime"
+}
+
 # ─── PRD detection ───────────────────────────────────────────────────────────
 
 # Find the PRD file in a project directory.

tools/prdy/prdy-init.sh

@@ -1,12 +1,12 @@
 #!/usr/bin/env bash
 set -euo pipefail
 #
-# prdy-init.sh — Create a new PRD via guided Claude session
+# prdy-init.sh — Create a new PRD via guided runtime session
 #
 # Usage:
 #   prdy-init.sh [--project <path>] [--name <feature>]
 #
-# Launches a dedicated Claude Code session in yolo mode with a specialized
+# Launches a dedicated runtime session in yolo mode with a specialized
 # system prompt that guides the user through PRD creation. The output is
 # written to docs/PRD.md.
 
@@ -24,15 +24,15 @@ while [[ $# -gt 0 ]]; do
     --name)    NAME="$2"; shift 2 ;;
     -h|--help)
       cat <<'USAGE'
-prdy-init.sh — Create a new PRD via guided Claude session
+prdy-init.sh — Create a new PRD via guided runtime session
 
 Usage: prdy-init.sh [--project <path>] [--name <feature>]
 
 Options:
   --project <path>   Project directory (default: CWD)
-  --name <feature>   Feature or project name (optional, Claude will ask if omitted)
+  --name <feature>   Feature or project name (optional, runtime will ask if omitted)
 
-Launches Claude Code in yolo mode with a PRD-focused system prompt.
+Launches the selected runtime in yolo mode with a PRD-focused prompt.
 The agent will ask clarifying questions, then write docs/PRD.md.
 
 Examples:
@@ -51,7 +51,8 @@ PROJECT="${PROJECT/#\~/$HOME}"
 
 # ─── Preflight checks ───────────────────────────────────────────────────────
 
-_require_cmd "claude"
+RUNTIME_CMD="$(prdy_runtime_command)"
+_require_cmd "$RUNTIME_CMD"
 
 # Check for existing PRD
 EXISTING="$(find_prd "$PROJECT")"
@@ -77,11 +78,29 @@ else
   KICKOFF="Create docs/PRD.md for this project. Read the project context first, then ask the user what they want to build. Ask clarifying questions before writing the PRD."
 fi
 
-# ─── Launch Claude ───────────────────────────────────────────────────────────
+# ─── Launch runtime ──────────────────────────────────────────────────────────
 
 info "Output target: $PROJECT/$PRD_CANONICAL"
-info "Mode: PRD Creation (yolo)"
+info "Mode: PRD Creation (yolo, runtime: $RUNTIME_CMD)"
 echo ""
 
 cd "$PROJECT"
-exec claude --dangerously-skip-permissions --append-system-prompt "$SYSTEM_PROMPT" "$KICKOFF"
+if [[ "$RUNTIME_CMD" == "claude" ]]; then
+  exec claude --dangerously-skip-permissions --append-system-prompt "$SYSTEM_PROMPT" "$KICKOFF"
+fi
+
+if [[ "$RUNTIME_CMD" == "codex" ]]; then
+  CODEX_PROMPT="$(cat <<EOF
+Follow this PRD contract exactly.
+
+$SYSTEM_PROMPT
+
+Task:
+$KICKOFF
+EOF
+)"
+  exec codex --dangerously-bypass-approvals-and-sandbox "$CODEX_PROMPT"
+fi
+
+fail "Unsupported runtime: $RUNTIME_CMD"
+exit 1

tools/prdy/prdy-update.sh

@@ -1,12 +1,12 @@
 #!/usr/bin/env bash
 set -euo pipefail
 #
-# prdy-update.sh — Update an existing PRD via guided Claude session
+# prdy-update.sh — Update an existing PRD via guided runtime session
 #
 # Usage:
 #   prdy-update.sh [--project <path>]
 #
-# Launches a dedicated Claude Code session in yolo mode with a specialized
+# Launches a dedicated runtime session in yolo mode with a specialized
 # system prompt that reads the existing PRD and guides targeted modifications.
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
@@ -21,14 +21,14 @@ while [[ $# -gt 0 ]]; do
     --project) PROJECT="$2"; shift 2 ;;
     -h|--help)
       cat <<'USAGE'
-prdy-update.sh — Update an existing PRD via guided Claude session
+prdy-update.sh — Update an existing PRD via guided runtime session
 
 Usage: prdy-update.sh [--project <path>]
 
 Options:
   --project <path>   Project directory (default: CWD)
 
-Launches Claude Code in yolo mode with a PRD-update system prompt.
+Launches the selected runtime in yolo mode with a PRD-update prompt.
 The agent will read the existing docs/PRD.md, summarize its state,
 and ask what changes are needed.
 
@@ -47,7 +47,8 @@ PROJECT="${PROJECT/#\~/$HOME}"
 
 # ─── Preflight checks ───────────────────────────────────────────────────────
 
-_require_cmd "claude"
+RUNTIME_CMD="$(prdy_runtime_command)"
+_require_cmd "$RUNTIME_CMD"
 
 # Require existing PRD
 EXISTING="$(find_prd "$PROJECT")"
@@ -65,11 +66,29 @@ SYSTEM_PROMPT="$(build_prdy_system_prompt "update")"
 
 KICKOFF="Read the existing PRD at ${EXISTING}, summarize its current state, then ask what changes or additions are needed."
 
-# ─── Launch Claude ───────────────────────────────────────────────────────────
+# ─── Launch runtime ──────────────────────────────────────────────────────────
 
 info "Updating: $EXISTING"
-info "Mode: PRD Update (yolo)"
+info "Mode: PRD Update (yolo, runtime: $RUNTIME_CMD)"
 echo ""
 
 cd "$PROJECT"
-exec claude --dangerously-skip-permissions --append-system-prompt "$SYSTEM_PROMPT" "$KICKOFF"
+if [[ "$RUNTIME_CMD" == "claude" ]]; then
+  exec claude --dangerously-skip-permissions --append-system-prompt "$SYSTEM_PROMPT" "$KICKOFF"
+fi
+
+if [[ "$RUNTIME_CMD" == "codex" ]]; then
+  CODEX_PROMPT="$(cat <<EOF
+Follow this PRD contract exactly.
+
+$SYSTEM_PROMPT
+
+Task:
+$KICKOFF
+EOF
+)"
+  exec codex --dangerously-bypass-approvals-and-sandbox "$CODEX_PROMPT"
+fi
+
+fail "Unsupported runtime: $RUNTIME_CMD"
+exit 1