Constraint Check

constraint-check

Purpose

The internal affairs department for Rune skills. Checks whether HARD-GATEs and mandatory constraints were actually followed during a workflow — not just claimed to be followed. Reads the constraint definitions from skill files and audits the conversation trail for compliance.

While completion-gate checks if claims have evidence, constraint-check checks if the PROCESS was followed. Did you actually write tests before code? Did you actually get plan approval? Did you actually run sentinel?

Triggers

• Called by cook (L1) at end of workflow as discipline audit
• Called by team (L1) to verify stream agents followed constraints
• Called by audit (L2) during quality dimension assessment
• /rune constraint-check — manual audit of current session

Calls (outbound)

None — pure read-only validator.

Called By (inbound)

• cook (L1): end-of-workflow discipline audit
• team (L1): verify stream agent compliance
• audit (L2): quality dimension
• User: manual session audit

Execution

Step 1 — Identify Active Skills

Parse the conversation/workflow to identify which skills were invoked:

Extract from context:
  - Skills invoked via Skill tool (exact list)
  - Skills referenced in agent narrative
  - Phase progression (cook phases completed)

Step 2 — Load Constraint Definitions

For each invoked skill, extract HARD-GATEs and numbered constraints:

For each skill in invoked_skills:
  Read: skills//SKILL.md
  Extract:
    -  blocks → mandatory, violation = BLOCK
    - ## Constraints numbered list → required, violation = WARN
    - ## Mesh Gates table → required gates

Step 3 — Audit Compliance

Check each constraint against the conversation evidence:

| Constraint Type | How to Verify | Evidence Source | |---|---|---| | "MUST write tests BEFORE code" | Test file Write/Edit timestamps before implementation Write/Edit | Tool call ordering | | "MUST get user approval" | User message containing "go"/"yes"/"proceed" after plan | Conversation history | | "MUST run verification" | Bash command with test/lint/build output | Tool call results | | "MUST show actual output" | Stdout captured in agent response | Agent messages | | "MUST NOT modify files outside scope" | Git diff files vs plan file list | Git + plan comparison | | "Iron Law: delete code before test" | No implementation code exists before test creation | Tool call ordering |

Step 4 — Classify Violations

| Violation Type | Severity | Meaning | |---------------|----------|---------| | HARD-GATE violation | BLOCK | Skill says this is non-negotiable | | Constraint violation | WARN | Skill says this is required but not fatal | | Best practice skip | INFO | Recommended but optional |

Step 5 — Report

## Constraint Check Report
- **Status**: COMPLIANT | VIOLATIONS_FOUND | CRITICAL_VIOLATION
- **Skills Audited**: [count]
- **Constraints Checked**: [count]
- **Violations**: [count by severity]

### HARD-GATE Violations (BLOCK)
- [skill:test] Iron Law: implementation code written at tool_call #12 BEFORE test file created at #15
- [skill:cook] Plan Gate: Phase 4 started without user approval message

### Constraint Violations (WARN)
- [skill:verification] Constraint 2: "All tests pass" claimed at message #20 without stdout evidence
- [skill:sentinel] Constraint 3: files scanned list not included in report

### Compliance Summary
| Skill | HARD-GATEs | Constraints | Status |
|-------|-----------|-------------|--------|
| cook | 3/3 ✓ | 6/7 (1 WARN) | WARN |
| test | 0/1 ✗ | 8/9 (1 WARN) | BLOCK |
| verification | 1/1 ✓ | 4/6 (2 WARN) | WARN |
| sentinel | 1/1 ✓ | 7/7 ✓ | PASS |

### Remediation
- BLOCK: test Iron Law — delete implementation, restart with test-first
- WARN: verification — re-run and capture stdout

Constraint Catalog (Quick Reference)

Key HARD-GATEs across skills that constraint-check audits:

| Skill | HARD-GATE | Check Method | |---|---|---| | test | Tests BEFORE code (Iron Law) | Tool call ordering | | cook | Scout before plan, plan before code | Phase progression | | plan | Every code phase has test entry | Plan content | | verification | Evidence for every claim | Stdout capture | | sentinel | BLOCK = halt pipeline | No commit after BLOCK | | preflight | BLOCK = halt pipeline | No commit after BLOCK | | debug | No code changes during debug | No Write/Edit in debug | | debug | 3-fix escalation | Fix attempt counter | | brainstorm | No implementation before approval | User message check |

Output Format

Constraint Check Report with status (COMPLIANT/VIOLATIONSFOUND/CRITICALVIOLATION), HARD-GATE violations, constraint violations, compliance summary table, and remediation steps. See Step 5 Report above for full template.

Constraints

1. MUST check all HARD-GATEs for every invoked skill — not just the ones that seem relevant
2. MUST use tool call ordering (not agent narrative) to verify temporal constraints
3. MUST distinguish HARD-GATE violations (BLOCK) from constraint violations (WARN)
4. MUST report specific evidence for each violation — not just "violated"
5. MUST NOT accept agent's self-report as compliance evidence — check independently

Sharp Edges

| Failure Mode | Severity | Mitigation | |---|---|---| | Agent self-reports compliance and constraint-check trusts it | CRITICAL | Constraint 5: check tool calls independently, not agent narrative | | Only checking cook constraints, missing test/sentinel/etc | HIGH | Constraint 1: audit ALL invoked skills, not just the orchestrator | | Temporal check wrong (tool calls reordered in context) | MEDIUM | Use tool call sequence numbers, not message ordering | | Too strict on optional steps (INFO treated as BLOCK) | LOW | Step 4 classification: only HARD-GATE = BLOCK, constraints = WARN |

Done When

• All invoked skills identified from context
• HARD-GATEs and constraints extracted from each skill's SKILL.md
• Each constraint checked against conversation evidence
• Violations classified as BLOCK/WARN/INFO
• Compliance summary table emitted per skill
• Remediation steps listed for each violation

Cost Profile

~1000-2000 tokens input, ~500-1000 tokens output. Haiku for speed — reads skill files and checks tool call ordering.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Rune-kit
• Source: Rune-kit/rune
• License: MIT

Install and usage instructions live in the source repository linked above.