Design: Work flow simulation and validation

Validate GGT designs through simulation before implementation.

## Validation Approaches

### 1. Dry-Run Simulation (Recommended First)
Mayor walks through scenarios mentally/on paper:
- "If polecat Toast signals done with dirty git state, what happens?"
- "If Witness context fills mid-verification, what state is lost?"
- "If two polecats try to close same issue, what happens?"

Create beads for any gaps discovered.

### 2. Real Work in gastown-py
Use Python Gas Town to stress-test assumptions:
- Run actual batch work on test repos
- Observe edge cases in practice
- Document issues found

### 3. Edge Case Analysis
Systematic review of failure modes:
- Agent crashes mid-operation
- Network failures during sync
- Concurrent access to shared state
- Context limits hit at bad times

## Key Scenarios to Validate

- [ ] Witness session cycling (state preservation)
- [ ] Polecat decommission with dirty state
- [ ] Merge conflicts in queue
- [ ] Beads sync conflicts between workers
- [ ] Escalation path (stuck worker -> Mayor)
- [ ] Cross-rig communication
- [ ] Federation mail routing (future)

## Success Criteria

- No data loss scenarios identified
- Clear recovery paths for all failure modes
- Edge cases either handled or documented as limitations
- Design improves as model cognition improves

## Output

For each scenario validated:
1. Document in relevant bead if issue found
2. Create new beads for missing functionality
3. Update architecture.md if design changes


gt spawn --create should auto-add polecat if missing

## Problem

`gt spawn gastown --issue gt-xxx --create` fails if no polecats exist.

## Current Behavior

```
Error: auto-select polecat: no available polecats in rig 'gastown'
```

## Expected Behavior

`--create` should:
1. Create a new polecat if none exist
2. Or create the specified polecat if `gt spawn gastown/NewName --create`

## Workaround

Must manually run `gt polecat add gastown Name` first.

## Principle

Agent UX should be forgiving - if I say spawn with --create, make it work.


Polecat health check loop

Implement the Witness health check loop:

Every 60 seconds:
1. List active polecats (gt polecats <rig>)
2. For each polecat, check:
   - Is tmux session still alive?
   - Is there a state.json with recent update?
   - Has there been git activity recently?
3. If stuck (no activity for configurable threshold):
   - First: nudge (send message asking for status)
   - Second: escalate to Mayor
   - Third: force kill after human confirmation

This is the 'health monitor' part of Witness.


CLI: witness commands (start, stop, status)

Witness daemon CLI commands.

## Commands

### gt witness start
Start the witness daemon for a rig.
```
gt witness start <rig> [--interval <seconds>]
```
- Starts background daemon process
- Default heartbeat interval: 30s
- Logs to <rig>/witness/witness.log

### gt witness stop
Stop the witness daemon.
```
gt witness stop <rig>
```
- Graceful shutdown
- Completes current heartbeat cycle

### gt witness status
Show witness status.
```
gt witness status <rig> [--json]
```
Output:
- Running/stopped
- Last heartbeat time
- Polecats being monitored
- Recent nudges/escalations

### gt witness logs
View witness logs.
```
gt witness logs <rig> [--follow] [--lines <n>]
```
- --follow: Continuous output (like tail -f)
- --lines: Number of lines (default 50)

## Daemon Management

Witness runs as background process:
- PID stored in <rig>/witness/witness.pid
- Uses nohup for persistence
- Logs structured JSON events

## Implementation

```go
var witnessCmd = &cobra.Command{Use: "witness"}
witnessCmd.AddCommand(startCmd, stopCmd, statusCmd, logsCmd)
```

Start launches daemon via exec, status reads PID file and pings process.


CLI: gt stop --all (emergency swarm kill)

Emergency kill command for swarm operations.

## Commands

```bash
gt stop --all              # Kill ALL sessions across all rigs
gt stop --rig <name>       # Kill all sessions in one rig
gt stop --rig <name> --graceful  # Try graceful first, then force
```

## Implementation

### --all flag
1. List all tmux sessions matching gt-*
2. For each: capture final output, kill session
3. Update all polecat states to idle
4. Log all killed sessions
5. Send mail to Mayor: "Emergency stop executed"

### --rig flag
1. List sessions for specific rig
2. Same as above but scoped

### --graceful flag
1. First, try to inject "exit" command
2. Wait 5 seconds
3. If still running, force kill

## Output

```
Stopping all Gas Town sessions...
  [wyvern] Toast: captured output, killed
  [wyvern] Capable: captured output, killed
  [beads] Nux: captured output, killed

3 sessions stopped.
All polecat states set to 'idle'.
Mail sent to mayor/.
```

## Safety

- Always capture output before killing
- Update state files to reflect reality
- Log all operations to gt.log
- Warn if uncommitted changes detected (but still kill)

## Dependencies

Needs: Tmux wrapper, Session management, Polecat management


Plugin: plan-oracle (work decomposition)

Plugin that helps decompose epics/issues into sub-tasks. Analyzes scope, identifies dependencies, estimates complexity for parallelization, creates beads for sub-tasks with dependency links.


/restart: Personal slash command for in-place agent restart

Create ~/.claude/commands/restart.md that restarts current Gas Town agent in place.

## Detection
- Read tmux session name: gt-mayor, gt-witness-*, gt-refinery-*, gt-polecat-*
- Fallback: check GT_ROLE env var

## Behavior by role
- mayor: gt mayor restart (sends Ctrl-C, loop respawns)
- witness: gt witness restart
- refinery: gt refinery restart
- polecat: gt polecat restart (or witness-mediated)

## Command format
Uses backticks for inline bash to detect context, then instructs Claude to run appropriate restart.


Failure handling: assign back to worker, add labels

Handle merge failures appropriately.

Failure types and actions:
| Failure     | Action                                      |
|-------------|---------------------------------------------|
| conflict    | Add needs-rebase label, assign to worker    |
| tests_fail  | Add needs-fix label, assign to worker       |
| build_fail  | Add needs-fix label, assign to worker       |
| flaky_test  | Retry once, then treat as tests_fail        |
| push_fail   | Retry with backoff, escalate if persistent  |

Actions:
1. bd update <id> --status=open --assignee=<worker>
2. bd update <id> --labels=<failure-label>
3. Send mail to worker explaining failure
4. Log failure details

Reference: docs/merge-queue-design.md#handling-failures


File locking for concurrent access

Add file locking for concurrent access safety.

## At-Risk Files
- .gastown/swarms.json (or per-swarm state.json)
- .gastown/refinery.json
- polecats/<name>/state.json
- inbox.jsonl files

## Go File Locking
Use syscall.Flock for advisory locking:
```go
type FileLock struct {
    file *os.File
}

func AcquireLock(path string, timeout time.Duration) (*FileLock, error) {
    f, err := os.OpenFile(path+".lock", os.O_CREATE|os.O_RDWR, 0644)
    if err != nil {
        return nil, err
    }
    // Use syscall.Flock with timeout
}

func (l *FileLock) Release() error
```

## Integration Pattern
```go
func (m *Manager) saveState(ref *Refinery) error {
    lock, err := AcquireLock(m.stateFile(), 5*time.Second)
    if err != nil {
        return fmt.Errorf("could not acquire lock: %w", err)
    }
    defer lock.Release()

    // Read-modify-write cycle
}
```

## New Package
internal/filelock/
├── lock.go     # FileLock, AcquireLock
└── lock_test.go

## Apply To
- internal/refinery/manager.go: loadState/saveState
- internal/cmd/swarm.go: SwarmStore
- internal/mail/mailbox.go: Append, rewrite
- internal/polecat/manager.go: state operations

## Timeout Handling
Default 5 second timeout. Return error if lock not acquired.

## Acceptance Criteria
- [ ] Lock files created (.lock extension)
- [ ] Timeout on lock contention
- [ ] All state files protected
- [ ] Locks released on error paths


Test2

Testing gt mail


Implement gt mq CLI commands

Add gt mq subcommands as sugar over bd:

- gt mq submit: Create MR for current branch
- gt mq list: Show open merge requests
- gt mq next: Show next MR ready to process
- gt mq process: Engineer processes the queue
- gt mq reorder <id> --after <x>: Change ordering via deps
- gt mq status <id>: Show MR details

All commands should work with the Beads data plane.