multi-agent-mux/.agents/skills/multi-agent-mux-stop/SKILL.md

---
name: multi-agent-mux-stop
description: "Stop an agent herdr session (claude, antigravity/agy) and update .mam/agent-sessions.yaml. Default stops gracefully and marks status=stopped with conversation preserved for resume. Does NOT delete on-disk conversation artifacts (jsonl/db) — those are preserved unless --purge-conversation is passed. Use when ending a work session, switching to a different one, or cleaning up before a fresh start."
version: 4.4.0
author: godopu
license: MIT
platforms: [linux, macos]
environments: [terminal, herdr]
metadata:
  hermes:
    tags: [agent, herdr, claude, antigravity, agy, multi-agent, stop, terminate, cleanup]
    related_skills: [multi-agent-mux-create, multi-agent-mux-resume, multi-agent-mux-monitor]
    prereq_skills: [multi-agent-mux-create, multi-agent-mux-resume]
---

# Multi-Agent Stop — Stop an Agent herdr Session

> **Companion skills**: `multi-agent-mux-create` (start), `multi-agent-mux-resume` (re-attach), `multi-agent-mux-monitor` (live status).
> **Herdr Isolation**: `stop` 명령은 YAML의 `herdr_session` 필드를 자동으로 파싱하여 해당 격리 서버의 세션을 안전하게 종료(kill)하므로, `HERDR_SESSION_NAME` 환경변수를 수동으로 지정할 필요가 없습니다. (`--herdr-workspace`는 CLI 대칭성을 위해 파서에서 허용되지만 소켓 라우팅에는 영향을 주지 않습니다.)
> **Single source of truth**: `./.mam/agent-sessions.yaml`.

## What this skill does

Stop an agent's herdr session gracefully, resolve and store the conversation ID, and **mark the YAML entry (status=stopped)**. Preserves:

- The herdr session's recorded `pane.pid / cmd / cwd / mcp_attachments` for audit
- The agent's on-disk conversation (claude `*.jsonl`, agy `conversations/*.db`) — so the user can `multi-agent-mux-resume` later
- The `start_command` so a future `multi-agent-mux-create --session <name>` reproduces the same herdr spec

The stop command is always **graceful by default**:
1. Sends exit keys to the agent TUI (`/exit` for Claude, `Exit` for Agy) and waits 3 seconds.
2. If still alive, issues `herdr kill-session` (SIGTERM) and waits 5 seconds.
3. If still alive, kills the pane PID via SIGKILL (`kill -9`) as a last resort.
4. Auto-captures the conversation ID into the row (`claude_session_id_own`/`agy_conversation_id_own`) before killing, ensuring the next resume uses a race-free tier-1 lookup.

## Pre-flight

```bash
SESSION_NAME=<workspace>-creator-<agent>  # convention
AGENT=claude                              # claude | agy | hermes | grok | opencode | codex — always pass it
AGENT_SESSIONS_YAML=.mam/agent-sessions.yaml

# 1) Session is registered?
python3 -c "
import yaml
d = yaml.safe_load(open('$AGENT_SESSIONS_YAML'))
names = [s['name'] for s in d.get('herdr_sessions', [])]
if '$SESSION_NAME' not in names:
    print('NOT in YAML — refusing to stop (no audit trail). Use multi-agent-mux-create first, or pass --force-no-yaml.')
    raise SystemExit(1)
"

# 2) Already stopped?
ALREADY=$(python3 -c "
import yaml
d = yaml.safe_load(open('$AGENT_SESSIONS_YAML'))
s = [x for x in d['herdr_sessions'] if x['name']=='$SESSION_NAME'][0]
print(s.get('status', 'unknown'))
")
if [ "$ALREADY" = "stopped" ]; then
  echo "Already stopped."
fi
```

## Workflow

```bash
# 1. Stop gracefully (default — captures ID, shuts down safely, status=stopped)
bash .agents/skills/multi-agent-mux-stop/scripts/stop_session.sh \
  --session "$SESSION_NAME" --agent "$AGENT"

# 2. Stop gracefully + record a custom stop reason
bash .agents/skills/multi-agent-mux-stop/scripts/stop_session.sh \
  --session "$SESSION_NAME" --agent "$AGENT" --reason api_error

# 3. Stop gracefully + clean up on-disk conversation (DANGEROUS)
#    — this prevents any future resume (status=terminated, resumable=false).
bash .agents/skills/multi-agent-mux-stop/scripts/stop_session.sh \
  --session "$SESSION_NAME" --agent "$AGENT" --purge-conversation
```

**Idempotency**: if the row is already `status: stopped`, the script prints `already stopped (...)` and exits 0 — re-running is a safe no-op.

**`--agent` is the standard.** Pass it on every invocation. If omitted, the script
resolves the agent from the registry record — the row's `agent` field, then the
session-name suffix, then `pane.cmd` — and exits 2 if none of the three resolve.
The fallback exists for recovery, not as the normal calling convention: a session
whose name carries no agent suffix (e.g. `agy-creator-01`) is only resolvable
while its registry row survives.

### State machine

```
running ──(stop default / --reason)────────► stopped      (resumable:true, conv preserved)
running ──(stop --purge-conversation --yes)► terminated   (resumable:false, conv deleted)
stopped ──(stop default … again)───────────► stopped      (idempotent no-op)
```

Fields written in STOP mode: `status: stopped`, `stopped_at`, `stopped_at_epoch`, `stop_reason`, `termination_mode: graceful`, `claude_session_id_own`/`agy_conversation_id_own` and `resumable: true`.

If `--purge-conversation` is used: `status: terminated`, `terminated_at`, `terminated_at_epoch`, `termination_mode: purge` and `resumable: false`.

The script:
1. Verifies the session is in agent-sessions.yaml
2. If `delegate_job_id` is set, automatically publishes a `progress --detail "terminating"` event to the multi-agent-mux-delegate-job registry
3. Captures the `last_visible_status` from `herdr capture-pane` (so we have a final TUI snapshot for audit)
4. Attempts graceful exit keys → SIGTERM kill-session → SIGKILL fallback
5. For `purge-conversation`: deletes `~/.claude/projects/.../jsonl` (claude) or `~/.gemini/antigravity-cli/conversations/...db` + `brain/...` (agy)
6. Updates the YAML entry and SQLite database atomically
7. If `delegate_job_id` is set, publishes a `completed` event to the multi-agent-mux-delegate-job registry

## Pitfalls

- **Don't delete on-disk artifacts by default** — the agent's `*.jsonl` / `conversations/*.db` is the data that `multi-agent-mux-resume` needs. `--purge-conversation` is for when the user is genuinely done with the conversation and wants zero recovery chance.
- **YAML is append-only until you write a stop** — if a previous run left the entry as `running` but herdr is actually dead (crash, host reboot), the YAML is stale. Running `multi-agent-mux-stop` will detect "herdr already dead, just update YAML" and proceed.
- **Don't delete the `claude_session_id_own: null` placeholder** — when the user creates a fresh session with `multi-agent-mux-create` and never sent a message, the entry has `claude_session_id_own: null`. Stopping must preserve that field.
- **Monitor skill may still be tracking** — if `multi-agent-mux-monitor` is running a heartbeat loop, stopping a session while it watches will trigger its `herdr ls != yaml` reconciliation. That's expected — let the monitor run, it will mark the entry as `terminated` on its own.

## Verification

```bash
# 1. herdr gone (real native command — `herdr has-session` is a lib.sh
#    tmux-compat pseudo-command and needs `source .agents/skills/lib.sh` first)
herdr agent get "$SESSION_NAME" >/dev/null 2>&1 && echo "STILL ALIVE" || echo "OK: herdr gone"

# 2. YAML has stopped entry
python3 -c "
import yaml
d = yaml.safe_load(open('$AGENT_SESSIONS_YAML'))
s = [x for x in d['herdr_sessions'] if x['name']=='$SESSION_NAME'][0]
assert s['status'] == 'stopped', f'expected stopped, got {s[\"status\"]}'
assert s.get('stopped_at'), 'missing stopped_at'
print(f'OK: stopped at {s[\"stopped_at\"]}')
print(f'  preserved: pane.pid={s[\"pane\"][\"pid\"]}, cmd={s[\"pane\"][\"cmd\"]}, cwd={s[\"pane\"][\"cwd\"]}')
"

# 3. (if --purge-conversation) disk artifacts gone
[ -f "${CLAUDE_PROJECT_DIR:-$HOME/.claude/projects}/<projkey>/<uuid>.jsonl" ] && echo "WARN: jsonl still exists" || echo "OK: jsonl purged"
```

## When NOT to use this skill

- **Just detaching** → there's no `herdr detach` CLI command; press the herdr detach keybinding inside the pane, or just close the terminal. The herdr session keeps running.
- **Stopping the agent inside but keeping herdr** → send `Ctrl-C` or `/exit` (claude) / `Ctrl-D` (agy) via `herdr agent send <target> <text>` (real native command; `herdr send-keys` is a lib.sh tmux-compat pseudo-command that needs `source .agents/skills/lib.sh` first). The herdr session stays but the agent process is gone.
- **Replacing an existing session with a new one** → `multi-agent-mux-stop` first, then `multi-agent-mux-create`.