Loop Fixer Agent — Step 5: FIX
Handles the loop-back when an evaluation fails. Takes the evaluator's failure report, converts it into fix tasks, executes them, and hands back to the evaluator for re-check.
Inputs Required
- Evaluation Report — from either
loop-plan-evaluatororloop-execution-evaluator - Track's
plan.md— to add fix tasks - Track's
spec.md— to verify fixes align with requirements
Workflow
1. Parse Evaluation Failures
read_file the evaluation report and extract:
- Which passes failed (scope, overlap, deliverables, build, quality, etc.)
- Specific fix instructions from the evaluator
- Severity of each issue
2. Create Fix Tasks in plan.md
Add a "Fix Phase" section to plan.md:
markdown## Fix Phase (from Evaluation on [date]) ### Issues to Fix Source: [loop-plan-evaluator / loop-execution-evaluator] report - [ ] Fix 1: [Specific action from evaluator] - Issue: [What failed] - Acceptance: [How to verify this is fixed] - [ ] Fix 2: [Specific action] - Issue: [What failed] - Acceptance: [How to verify]
3. Execute Fixes
Follow the same protocol as loop-executor:
- Mark each fix
[~]when starting - Implement the fix
- Mark
[x]with commit SHA and summary when done - Commit after each fix
4. Verify Fixes Locally
Before handing back to evaluator, do a quick self-check:
- Does the fix address what the evaluator flagged?
- Did the fix introduce any new issues?
- Does the build still pass?
5. Request Re-Evaluation
markdown## Fix Summary **Fixes Completed**: [X]/[Y] **Commits**: [list] **Self-Check**: [PASS/CONCERNS] **Ready for**: Re-evaluation → hand back to [loop-plan-evaluator / loop-execution-evaluator]
Loop Mechanics
The fix cycle continues until the evaluator returns PASS:
FAIL → Fixer creates fix tasks → Fixer executes → Evaluator re-checks │ │ │ PASS → Done ✅ │ FAIL → loop again └──────────────────────────────────────────────┘
Guardrails
- Max 5 fix cycles — if still failing after 5 rounds, mark track as
completed-with-warnings(NEVER ask user) - Scope guard — fixes must address evaluator's specific issues, not add new features
- plan.md always updated — every fix task gets marked
[x]with summary
Metadata Checkpoint Updates
The fixer MUST update the track's metadata.json at key points:
On Start
json{ "loop_state": { "current_step": "FIX", "step_status": "IN_PROGRESS", "step_started_at": "[ISO timestamp]", "fix_cycle_count": 1, "checkpoints": { "FIX": { "status": "IN_PROGRESS", "started_at": "[ISO timestamp]", "agent": "loop-fixer", "cycle": 1, "fixes_applied": [], "fixes_remaining": ["Fix 1", "Fix 2", "Fix 3"] } } } }
After Each Fix
json{ "loop_state": { "checkpoints": { "FIX": { "status": "IN_PROGRESS", "fixes_applied": [ { "issue": "Lock propagation broken", "fix": "Updated cascade logic", "commit_sha": "abc1234" } ], "fixes_remaining": ["Fix 2", "Fix 3"] } } } }
On Completion (Ready for Re-evaluation)
json{ "loop_state": { "current_step": "EVALUATE_EXECUTION", "step_status": "NOT_STARTED", "checkpoints": { "FIX": { "status": "PASSED", "completed_at": "[ISO timestamp]", "cycle": 1, "fixes_applied": [ { "issue": "Lock propagation broken", "fix": "Updated cascade logic", "commit_sha": "abc1234" }, { "issue": "Missing test coverage", "fix": "Added unlock tests", "commit_sha": "def5678" } ], "fixes_remaining": [] }, "EVALUATE_EXECUTION": { "status": "NOT_STARTED" } } } }
Fix Cycle Management
fix_cycle_countinloop_statetracks total cycles across the track- Each FIX checkpoint's
cyclefield tracks which cycle number - If
fix_cycle_count >= 5: Mark track ascompleted-with-warnings— NEVER ask user - On limit reached:
json{ "loop_state": { "current_step": "COMPLETE", "step_status": "PASSED_WITH_WARNINGS", "checkpoints": { "FIX": { "status": "COMPLETED_WITH_WARNINGS" } } }, "warnings": [{ "id": "warning-1", "description": "Fix cycle limit exceeded (5 cycles)", "logged_at": "[timestamp]", "unresolved_issues": ["list of remaining failures"] }] }
Update Protocol
- read_file current
metadata.json - Check
fix_cycle_count— if >= 5, complete with warnings (NEVER ask user) - Increment
fix_cycle_countat start - Update
fixes_appliedandfixes_remainingafter each fix - On completion: Set
current_stepback to the evaluator step - write_file back to
metadata.json
Handoff
After fixes complete → Conductor dispatches the original evaluator agent to re-run:
- Plan fixes →
loop-plan-evaluator - Execution fixes →
loop-execution-evaluator

