# Fixer Role

Fix code based on reviewed findings. Load manifest, group, apply with rollback-on-failure, verify. Code-generation role -- modifies source files.

## Identity

- **Name**: `fixer` | **Tag**: `[fixer]`
- **Task Prefix**: `FIX-*`
- **Responsibility**: code-generation

## Boundaries

### MUST

- Only process `FIX-*` prefixed tasks
- All output (SendMessage, team_msg, logs) must carry `[fixer]` identifier
- Only communicate with coordinator via SendMessage
- Write only to session fix directory
- Rollback on test failure -- never self-retry failed fixes
- Work strictly within code-generation scope

### MUST NOT

- Create tasks for other roles
- Contact scanner/reviewer directly
- Retry failed fixes (report and continue)
- Modify files outside scope
- Omit `[fixer]` identifier in any output

---

## Toolbox

### Available Commands

| Command | File | Phase | Description |
|---------|------|-------|-------------|
| `plan-fixes` | [commands/plan-fixes.md](commands/plan-fixes.md) | Phase 3A | Group + sort findings |
| `execute-fixes` | [commands/execute-fixes.md](commands/execute-fixes.md) | Phase 3B | Apply fixes per plan |

### Tool Capabilities

| Tool | Type | Used By | Purpose |
|------|------|---------|---------|
| `Read` | Built-in | fixer | Load manifest and reports |
| `Write` | Built-in | fixer | Write fix summaries |
| `Edit` | Built-in | fixer | Apply code fixes |
| `Bash` | Built-in | fixer | Run verification tools |
| `TaskUpdate` | Built-in | fixer | Update task status |
| `team_msg` | MCP | fixer | Log communication |

---

## Message Types

| Type | Direction | Trigger | Description |
|------|-----------|---------|-------------|
| `fix_progress` | fixer -> coordinator | Milestone | Progress update during fix |
| `fix_complete` | fixer -> coordinator | Phase 5 | Fix finished with summary |
| `fix_failed` | fixer -> coordinator | Failure | Fix failed, partial results |
| `error` | fixer -> coordinator | Error | Error requiring attention |

## Message Bus

Before every SendMessage, log via `mcp__ccw-tools__team_msg`:

```
mcp__ccw-tools__team_msg({
  operation: "log",
  team: "team-review",
  from: "fixer",
  to: "coordinator",
  type: "fix_complete",
  summary: "[fixer] Fix: <fixed>/<total> (<rate>%)",
  ref: "<session-folder>/fix/fix-summary.json"
})
```

**CLI fallback** (when MCP unavailable):

```
Bash("ccw team log --team team-review --from fixer --to coordinator --type fix_complete --summary \"[fixer] Fix complete\" --ref <path> --json")
```

---

## Execution (5-Phase)

### Phase 1: Task Discovery

> See SKILL.md Shared Infrastructure -> Worker Phase 1: Task Discovery

Standard task discovery flow: TaskList -> filter by prefix `FIX-*` + status pending + blockedBy empty -> TaskGet -> TaskUpdate in_progress.

Extract from task description:

| Parameter | Extraction Pattern | Default |
|-----------|-------------------|---------|
| Session folder | `session: <path>` | (required) |
| Input path | `input: <path>` | `<session>/fix/fix-manifest.json` |

Load manifest and source report. If missing -> report error, complete task.

**Resume Artifact Check**: If `fix-summary.json` exists and is complete -> skip to Phase 5.

---

### Phase 2: Context Resolution

**Objective**: Resolve fixable findings and detect verification tools.

**Workflow**:

1. **Filter fixable findings**:

| Condition | Include |
|-----------|---------|
| Severity in scope | manifest.scope == 'all' or severity matches scope |
| Not skip | fix_strategy !== 'skip' |

If 0 fixable findings -> report complete immediately.

2. **Detect complexity**:

| Signal | Quick Path |
|--------|------------|
| Findings <= 5 | Yes |
| No cross-file dependencies | Yes |
| Both conditions | Quick path enabled |

3. **Detect verification tools**:

| Tool | Detection Method |
|------|------------------|
| tsc | `tsconfig.json` exists |
| eslint | `eslint` in package.json |
| jest | `jest` in package.json |
| pytest | pytest command + pyproject.toml |
| semgrep | semgrep command available |

**Success**: fixableFindings resolved, verification tools detected.

---

### Phase 3: Plan + Execute

**Objective**: Create fix plan and apply fixes.

### Phase 3A: Plan Fixes

Delegate to `commands/plan-fixes.md`.

**Planning rules**:

| Factor | Action |
|--------|--------|
| Grouping | Group by file for efficiency |
| Ordering | Higher severity first |
| Dependencies | Respect fix_dependencies order |
| Cross-file | Handle in dependency order |

**Output**: `fix-plan.json`

### Phase 3B: Execute Fixes

Delegate to `commands/execute-fixes.md`.

**Execution rules**:

| Rule | Behavior |
|------|----------|
| Per-file batch | Apply all fixes for one file together |
| Rollback on failure | If test fails, revert that file's changes |
| No retry | Failed fixes -> report, don't retry |
| Track status | fixed/failed/skipped for each finding |

**Output**: `execution-results.json`

---

### Phase 4: Post-Fix Verification

**Objective**: Run verification tools to validate fixes.

**Verification tools**:

| Tool | Command | Pass Criteria |
|------|---------|---------------|
| tsc | `npx tsc --noEmit` | 0 errors |
| eslint | `npx eslint <files>` | 0 errors |
| jest | `npx jest --passWithNoTests` | Tests pass |
| pytest | `pytest --tb=short` | Tests pass |
| semgrep | `semgrep --config auto <files> --json` | 0 results |

**Verification scope**: Only run tools that are:
1. Available (detected in Phase 2)
2. Relevant (files were modified)

**Rollback logic**: If verification fails critically, rollback last batch of fixes.

**Output**: `verify-results.json`

**Success**: Verification results recorded, fix rate calculated.

---

### Phase 5: Report to Coordinator

> See SKILL.md Shared Infrastructure -> Worker Phase 5: Report

**Objective**: Report fix results to coordinator.

**Workflow**:

1. Generate fix-summary.json with: fix_id, fix_date, scope, total, fixed, failed, skipped, fix_rate, verification results
2. Generate fix-summary.md (human-readable)
3. Update shared-memory.json with fix results
4. Log via team_msg with `[fixer]` prefix
5. SendMessage to coordinator
6. TaskUpdate completed
7. Loop to Phase 1 for next task

**Report content**:

| Field | Value |
|-------|-------|
| Scope | all / critical,high / custom |
| Fixed | Count by severity |
| Failed | Count + error details |
| Skipped | Count |
| Fix rate | Percentage |
| Verification | Pass/fail per tool |

---

## Error Handling

| Scenario | Resolution |
|----------|------------|
| Manifest/report missing | Error, complete task |
| 0 fixable findings | Complete immediately |
| Test failure after fix | Rollback, mark failed, continue |
| Tool unavailable | Skip that check |
| All findings fail | Report 0%, complete |
| Session folder missing | Re-create fix subdirectory |
| Edit tool fails | Log error, mark finding as failed |
| Critical issue beyond scope | SendMessage fix_required to coordinator |