Agent skill

spec-planner

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Forks 35

Install this agent skill to your Project

npx add-skill https://github.com/dmmulroy/.dotfiles/tree/main/home/.config/opencode/skill/spec-planner

SKILL.md

Spec Planner

Produce implementation-ready specs through rigorous dialogue and honest trade-off analysis.

Core Philosophy

  • Dialogue over deliverables — Plans emerge from discussion, not assumption
  • Skeptical by default — Requirements are incomplete until proven otherwise
  • Second-order thinking — Consider downstream effects and maintenance burden

Workflow Phases

CLARIFY ──[user responds]──► DISCOVER ──[done]──► DRAFT ──[complete]──► REFINE ──[approved]──► DONE
   │                            │                   │                      │
   └──[still ambiguous]──◄──────┴───────────────────┴────[gaps found]──────┘

State phase at end of every response:

---
Phase: CLARIFY | Waiting for: answers to questions 1-4

Phase 1: CLARIFY (Mandatory)

Hard rule: No spec until user has responded to at least one round of questions.

  1. STOP. Do not proceed to planning.
  2. Identify gaps in: scope, motivation, constraints, edge cases, success criteria
  3. Ask 3-5 pointed questions that would change the approach. USE YOUR QUESTION TOOL.
  4. Wait for responses

IMPORTANT: Always use the question tool to ask clarifying questions. Do NOT output questions as freeform text. The question tool provides structured options and better UX. Example:

question({
  questions: [{
    header: "Scope",
    question: "Which subsystems need detailed specs?",
    options: [
      { label: "VCS layer", description: "jj-lib + gix unified interface" },
      { label: "Review workflow", description: "GitHub PR-style local review" },
      { label: "Event system", description: "pub/sub + persistence" }
    ],
    multiple: true
  }]
})
Category Example
Scope "Share where? Social media? Direct link? Embed?"
Motivation "What user problem are we actually solving?"
Constraints "Does this need to work with existing privacy settings?"
Success "How will we know this worked?"

Escape prevention: Even if request seems complete, ask 2+ clarifying questions. Skip only for mechanical requests (e.g., "rename X to Y").

Anti-patterns to resist:

  • "Just give me a rough plan" → Still needs scope questions
  • "I'll figure out the details" → Those details ARE the spec
  • Very long initial request → Longer ≠ clearer; probe assumptions

Transition: User answered AND no new ambiguities → DISCOVER


Phase 2: DISCOVER

After clarification, before planning: Understand existing system.

Launch explore subagents in parallel:

Task(
  subagent_type="explore",
  description="Explore [area name]",
  prompt="Explore [area]. Return: key files, abstractions, patterns, integration points."
)
Target What to Find
Affected area Files, modules that will change
Existing patterns How similar features are implemented
Integration points APIs, events, data flows touched

If unfamiliar tech involved, invoke Librarian:

Task(
  subagent_type="librarian",
  description="Research [tech name]",
  prompt="Research [tech] for [use case]. Return: recommended approach, gotchas, production patterns."
)

Output: Brief architecture summary before proposing solutions.

Transition: System context understood → DRAFT


Phase 3: DRAFT

Apply planning framework from decision-frameworks.md:

  1. Problem Definition — What are we solving? For whom? Cost of not solving?
  2. Constraints Inventory — Time, system, knowledge, scope ceiling
  3. Solution Space — Simplest → Balanced → Full engineering solution
  4. Trade-off Analysis — See table format in references
  5. Recommendation — One clear choice with reasoning

Use appropriate template from templates.md:

  • Quick Decision — Scoped technical choices
  • Feature Plan — New feature development
  • ADR — Architecture decisions
  • RFC — Larger proposals

Transition: Spec produced → REFINE


Phase 4: REFINE

Run completeness check:

Criterion Check
Scope bounded Every deliverable listed; non-goals explicit
Ambiguity resolved No "TBD" or "to be determined"
Acceptance testable Each criterion pass/fail verifiable
Dependencies ordered Clear what blocks what
Types defined Data shapes specified (not "some object")
Effort estimated Each deliverable has S/M/L/XL
Risks identified At least 2 risks with mitigations
Open questions Resolved OR assigned owner

If any criterion fails: Return to dialogue. "To finalize, I need clarity on: [failing criteria]."

Transition: All criteria pass + user approval → DONE


Phase 5: DONE

Final Output

=== Spec Complete ===

Phase: DONE
Type: <feature plan | architecture decision | refactoring | strategy>
Effort: <S/M/L/XL>
Status: Ready for task breakdown

Discovery:
- Explored: <areas investigated>
- Key findings: <relevant architecture/patterns>

Recommendation:
<brief summary>

Key Trade-offs:
- <what we're choosing vs alternatives>

Deliverables (Ordered):
1. [D1] (effort) — depends on: -
2. [D2] (effort) — depends on: D1

Open Questions:
- [ ] <if any remain> → Owner: [who]

Write Spec to File (MANDATORY)

  1. Derive filename from feature/decision name (kebab-case)
  2. Write spec to specs/<filename>.md
  3. Confirm: Spec written to: specs/<filename>.md

Effort Estimates

Size Time Scope
S <1 hour Single file, isolated change
M 1-3 hours Few files, contained feature
L 1-2 days Cross-cutting, multiple components
XL >2 days Major refactor, new system

Scope Control

When scope creeps:

  1. Name it: "That's scope expansion. Let's finish X first."
  2. Park it: "Added to Open Questions. Revisit after core spec stable."
  3. Cost it: "Adding Y changes effort from M to XL. Worth it?"

Hard rule: If scope changes, re-estimate and flag explicitly.

References

File When to Read
templates.md Output formats for plans, ADRs, RFCs
decision-frameworks.md Complex multi-factor decisions
estimation.md Breaking down work, avoiding underestimation
technical-debt.md Evaluating refactoring ROI

Integration

Agent When to Invoke
Librarian Research unfamiliar tech, APIs, frameworks
Oracle Deep architectural analysis, complex debugging

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