# Decision Gate: Parallel Progress Tracker

**Branch**: `colonyos/add_a_parallel_progress_tracker_that_provides_real_time_visibility_into_concurre`
**PRD**: `cOS_prds/20260320_011056_prd_add_a_parallel_progress_tracker_that_provides_real_time_visibility_into_concurre.md`
**Date**: 2026-03-20

## Persona Verdicts

| Persona | Verdict | Round |
|---------|---------|-------|
| Andrej Karpathy | ✅ APPROVE | Round 2 |
| Linus Torvalds | ✅ APPROVE | Round 2 |
| Staff Security Engineer | ✅ APPROVE | Round 2 |
| Principal Systems Engineer | ✅ APPROVE | Round 2 |

**Tally**: 4/4 approve (100%)

## Findings Summary

### CRITICAL Issues
None identified.

### HIGH Issues
None identified.

### MEDIUM Issues
- **Verdict regex whitespace**: `\s*` allows zero whitespace in "VERDICT:approve" pattern (Andrej Karpathy). Mitigated by default-to-approved fallback.
- **TTY clear-to-EOL missing**: `_render_tty()` uses `\r` but doesn't emit `\x1b[K` to clear line remnants (Linus Torvalds). Cosmetic only.

### LOW Issues
- Elapsed time is global (since tracker start), not per-reviewer task start (Linus, Principal)
- Unused `Callable` import in test file (Linus)
- Docstring in `sanitize_display_text()` could be clearer about tab/newline stripping (Principal)
- No explicit thread-safety lock for `_states` dict (Andrej, Security) - acceptable given asyncio model

## Implementation Completeness

All 6 functional requirements from the PRD are implemented:
- ✅ FR-1: Parallel Progress Display
- ✅ FR-2: Cost Accumulator
- ✅ FR-3: Completion Events callback
- ✅ FR-4: TTY Detection and graceful degradation
- ✅ FR-5: Input Sanitization
- ✅ FR-6: Summary After Completion

## Test Coverage
- 72 new tests added
- 1,287 total tests pass with no regressions
- Key edge cases covered: callback exceptions, out-of-order completion, empty calls, ANSI injection

## Code Quality Observations
- Clean asyncio implementation using `asyncio.wait(FIRST_COMPLETED)`
- Proper exception isolation in callbacks
- Backward-compatible API (optional parameters with defaults)
- Defense-in-depth sanitization of persona names
