# Sprint 217-221 Execution Tracker - 2026-02-26

## Scope
Executed sprint plans:
- `sprint217_plan.md`
- `sprint218_plan.md`
- `sprint219_plan.md`
- `sprint220_plan.md`
- `sprint221_plan.md`

Observed run directories from sprint runner:
- `logs/taskitem_runs/sprint217_plan_20260226_124842`
- `logs/taskitem_runs/sprint218_plan_20260226_124842`
- `logs/taskitem_runs/sprint219_plan_20260226_124843`
- `logs/taskitem_runs/sprint220_plan_20260226_124843`
- `logs/taskitem_runs/sprint221_plan_20260226_124844`

Important status note:
- These sprint-run summary files report `total=0` and do **not** constitute validated execution closure by themselves.

## Implemented Changes

### Sprint 217-221 (contract-gate tranche)
- `tools/mcp/run_project_benchmark_matrix.sh`
  - enforces multi-file required-artifact contract for constrained tasks.
  - validates category-specific fullstack contracts:
    - `fullstack_api_evolution`: compatibility window required.
    - `state_migration`: rollback + `data_loss_allowed=false` required.
    - `security_propagation`: `deny_by_default=true` required.
    - `performance_budgeted_change`: SLO p95 required.
    - `rollout_choreography`: staged + auto-abort-on-error-budget-breach required.
  - emits deterministic strict blockers (`fullstack_contract_invalid:<reason>`).
- `tools/mcp/analyze_fullstack_contract_closure.py`
  - closure report generation by category with invalid-rate + AB/Prod readiness.

### Integration summaries
Added:
- `editor/src/Sprint217IntegrationSummary.h`
- `editor/src/Sprint218IntegrationSummary.h`
- `editor/src/Sprint219IntegrationSummary.h`
- `editor/src/Sprint220IntegrationSummary.h`
- `editor/src/Sprint221IntegrationSummary.h`

## Validation Runs (Meaningful Evidence)

Primary production-enabled validation:
- `logs/taskitem_runs/challenging_fullstack_multifile_20260226_r5/summary.json`
- `logs/taskitem_runs/challenging_fullstack_multifile_20260226_r5/results.jsonl`
- `logs/taskitem_runs/challenging_fullstack_multifile_20260226_r5/fullstack_contract_closure.json`

Headline metrics from `r5`:
- AB path readiness: `6/12` (`50%`) for Path A and Path B.
- Production loop readiness: `12/12` (`100%`).
- `fullstack_contract.invalid_runs=0` under strict mode.
- `false_green_candidates=0` (production evidence-complete criteria).
- `ab_prod_divergence_count=6` (all six C++ rows).

## Explicit Completion Signal

- Sprints 217-221 implementation: `IMPLEMENTED`
- Sprints 217-221 robustness closure: `PARTIAL`

Reason for `PARTIAL`:
- Contract gating is now enforced and validated.
- However, hard-suite behavior still shows major AB-vs-production divergence in C++ paths; this is not production-closure equivalent for deterministic generator parity.

## Follow-on Parity Recheck (r6)

- `logs/taskitem_runs/challenging_fullstack_multifile_20260226_r6/summary.json`
- parity mode enabled via `REQUIRE_AB_PARITY=1`
- result:
  - `ab_prod_divergence_count=0` (unresolved divergence eliminated)
  - `ab_consistency_blocked_count=6` (all six C++ rows blocked by parity gate)
  - production ready reduced to `6/12` (Python-only readiness)