Preflight
Use before starting delivery work. Pre-implementation validation checklist to ensure readiness.From its SKILL.md
npx -y skills add haabe/mycelium --skill preflightAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
SKILL.md
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Preflight Skill
Pre-delivery validation checklist. Run before every implementation task.
Checklist
Constraints (ALWAYS FIRST)
Before scoping any delivery work, establish constraints. Do not propose a plan before knowing the budget.
- Time budget: "How much time do you have for this?" (hours, days, sprint length)
- Resource constraints: Solo? Team? What skills are available?
- Fidelity: Demo/prototype vs. production? Who is the audience?
- Dependencies: Waiting on anything external?
If time budget < 8 hours, scope aggressively — one vertical slice, no polish. If the initial plan exceeds the time budget, cut scope before presenting it to the user.
Re-forecast trigger (audit-triggered / emergent work). Work that opens as "just address the recommendations", "quick fix", or any audit/assessment follow-up still gets a constraint pass — set an explicit estimate even when no one asked for one. Then, mid-session, re-forecast when the work crosses ~2× the estimate or when no estimate was ever set: stop, state actual-so-far vs estimate, and re-scope or re-confirm the budget before continuing. The failure this catches: emergent cycles that bypass preflight and balloon silently (dogfood cycle-history.yml — a "~2h" audit cycle ran ~9h; a "session-scope" one ran ~14h). The re-forecast becomes the calibration.effort_accuracy data point at /retrospective.
Source: Hoskins transcript (2026-04-25) — agent proposed 20-hour plan before learning user had 8 hours. Goldratt (Theory of Constraints — identify the constraint before optimizing). Corrections.md: "Over-scope before constraints." Re-forecast trigger from the 2026-06-15 /framework-health effort-calibration finding (audit-triggered cycles balloon past estimate).
Context
- corrections.md reviewed for relevant past mistakes
- patterns.md reviewed for applicable patterns
- Current diamond phase is Develop or Deliver
- Acceptance criteria are clear and measurable
- Scenarios linked:
.claude/canvas/scenarios.ymlhas scenarios for this solution, and acceptance criteria trace back to scenario success/failure states (Hoskins)
Scope
- Scope fits within the time budget declared above
- This is the smallest vertical slice that delivers value
- Scope is explicitly bounded (what is NOT included)
- No speculative features (YAGNI check)
- Dependencies identified and available
Technical / Production Readiness
Software/AI tool:
- Tech stack detected and understood
- Build/test/lint commands confirmed working
- Development environment functional
- Existing code patterns reviewed
Content:
- Production tools ready (editor, recording, hosting)
- Style guide / editorial standards available
- Existing content patterns reviewed
Service:
- Delivery tools ready (templates, scheduling, communication)
- Existing service patterns reviewed
Security (software, ai_tool, service with digital infra)
- Data classification understood for this feature
- Security requirements identified (auth, input validation, etc.)
- No secrets will be hardcoded
- Dependencies checked for known vulnerabilities
Accessibility
Software:
- Accessibility requirements identified
- Semantic HTML approach planned
- Keyboard interaction model defined
- Color contrast requirements noted
Content:
- Captions/transcripts planned for audio/video
- Alt text planned for images
- Readable typography confirmed
Validation Strategy
Software: Test approach defined (unit, integration, e2e), edge cases and error scenarios identified. Content: Review process defined (SME, self-checklist, fact-check), learning objectives mapped. AI tool: Eval test cases defined, red-team scenarios planned, bias testing approach chosen. Service: Walkthrough planned, client feedback mechanism defined.
Success Criteria (G-V11)
- Declare what will be true after this delivery increment (1-3 measurable statements)
- Declare how each criterion will be verified (test, manual check, metric)
- Record criteria in .claude/harness/decision-log.md alongside the delivery decision
Example:
Success criteria:
1. "Users can complete onboarding in < 5 min" — verified by usability test
2. "API responds in < 200ms at p95" — verified by load test
3. "No new lint or type errors introduced" — verified by CI
Definition of Done
- DoD criteria reviewed and understood
- All criteria are achievable within this task
If Any Item Fails
Do not proceed to implementation. Instead:
- Document what is missing.
- Determine the fastest path to readiness.
- Address the gap before starting delivery work.
Theory Citations
- Smart: BVSSH (Sooner -- avoid rework by preparing)
- Forsgren: Accelerate (reduce lead time by removing blockers early)
What ships with it
Read from the repository
Just SKILL.md. No reference files, no scripts.