diff --git a/skills/project-heartbeat/SKILL.md b/skills/project-heartbeat/SKILL.md
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+---
+name: project-heartbeat
+description: Keep active delegated projects from going silent by arming a 10-minute heartbeat timer after main reports progress, checking worker status when the timer expires, and pushing a fresh user-visible update until the project is done, paused, failed, or cancelled. Use when a project has active workers or outstanding milestones and the main agent needs anti-silence discipline.
+---
+
+# Project Heartbeat
+
+Use this skill to stop active projects from disappearing into silence.
+
+This skill exists because delegated projects can look alive while no user-visible update is happening:
+- main says work is in progress, then goes quiet
+- workers stall or launch-fail without being surfaced upward
+- the user has to ask "how is it going?" to get a status refresh
+
+## Purpose
+
+Create a simple project-level heartbeat loop:
+1. main gives a user-visible project update
+2. a 10-minute timer is armed
+3. if another meaningful update happens before timeout, reset the timer
+4. if timeout is reached, check active workers / project state
+5. send a fresh user-visible update
+6. repeat until the project is closed
+
+## States
+Use these states only:
+- `idle`
+- `armed`
+- `checking`
+- `closed`
+
+### Meaning
+- `idle`: no active heartbeat-monitored project
+- `armed`: project is active and the 10-minute silence timer is running
+- `checking`: timer expired; main is actively collecting status from workers / project state
+- `closed`: project is done, paused, failed, or cancelled; heartbeat stops
+
+## Trigger to arm
+Arm the heartbeat when:
+- main tells the user a project has started
+- main dispatches work and communicates that the project is active
+- main says it will continue work and more updates are expected
+
+Do not arm for:
+- one-shot answers
+- tiny tasks that are already done
+- passive discussion with no active project
+
+## Reset rule
+Reset the 10-minute timer when any of these happen:
+- main sends a meaningful project update to the user
+- a worker milestone/blocker/completion is forwarded to the user
+- the user sends a project-touching follow-up and main replies with real status
+
+A "meaningful update" must contain actual status, not filler.
+
+## Timeout rule
+If 10 minutes pass with no meaningful update while the project is active:
+1. switch to `checking`
+2. inspect active workers / project state
+3. determine whether the project is:
+   - still progressing
+   - blocked
+   - launch-failed
+   - stalled
+   - done
+4. send a user-visible update
+5. return to `armed` if still active, else `closed`
+
+## Worker check order
+When timeout fires, check in this order:
+1. worker session history / visible traces
+2. subagent/session visibility
+3. task state in `CURRENT_STATE.md`
+4. known blockers (model, auth, tool, path, review, external)
+
+If a worker was supposedly active but has no trace, prefer `blocked (launch failure)` over vague waiting language.
+
+## User update format
+Use the normal 4-line update format:
+- who
+- status
+- output
+- next
+
+## Close conditions
+Close the heartbeat when the project becomes:
+- `done`
+- `paused`
+- `failed`
+- `cancelled`
+
+If multiple sub-tasks belong to the same project, keep the heartbeat open until the overall project is closed.
+
+## Guardrails
+- Do not spam on a fixed timer if there is nothing meaningful to say; timeout should trigger a real status check first.
+- Do not keep the heartbeat alive after project closure.
+- Do not claim progress without evidence.
+- Silence is a process problem, not a neutral state.
+
+## References
+- For task-state rules and evidence gates: read `../agent-workflow/references/state-machine.md`
+- For reporting format: read `../agent-workflow/references/reporting.md`
+- For continuity workbench use: read `../memory-continuity/references/template.md`
diff --git a/skills/project-heartbeat/references/check-order.md b/skills/project-heartbeat/references/check-order.md
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+# Heartbeat timeout check order
+
+When the 10-minute timer expires:
+
+1. Check worker/session traces
+   - session history
+   - recent/active subagents
+   - visible logs / evidence points
+
+2. Check task state
+   - CURRENT_STATE.md
+   - planned / dispatching / in_progress / blocked / reviewing / done
+
+3. Check known blocker buckets
+   - launch
+   - model
+   - auth
+   - tool
+   - path/repo
+   - scope
+   - policy/review
+   - external
+
+4. Produce a user-visible update
+   - who
+   - status
+   - output
+   - next
+
+Prefer precise failure language over passive waiting language.
diff --git a/skills/project-heartbeat/references/state-machine.md b/skills/project-heartbeat/references/state-machine.md
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+# Project heartbeat state machine
+
+## States
+- idle
+- armed
+- checking
+- closed
+
+## Normal flow
+1. main sends a project-progress update -> `armed`
+2. 10-minute silence timer runs
+3. meaningful update arrives before timeout -> reset timer, remain `armed`
+4. timeout fires -> `checking`
+5. main inspects workers/project state and sends user-visible update
+6. if still active -> back to `armed`
+7. if done/paused/failed/cancelled -> `closed`
+
+## Failure patterns
+- no worker trace after supposed dispatch -> `blocked (launch failure)`
+- ETA missed with no milestone -> `blocked (stalled)`
+- model/auth/tool/path issues -> `blocked` with explicit reason