holocron/docs/issues/0021-implement-skills.md

0021 — Implement skills: implement-feature, tdd, refactor, diagnose

Type: HITL Parent PRD: docs/prd/chunk-3-skills-library.md

What to build

The 4 implement phase skills. One is new; three are preserved Pocock placeholders upgraded to the authoring standard. All authored via write-skill (0018), evals via write-eval (0017). write-docs has been moved to issue 0018 phase 2.

Skills, origins, and trigger descriptions:

Flat name	Origin	Trigger description
implement-feature	New	Implement a feature, build this, write the code for X
tdd	Preserved; frontmatter + standard added	TDD, test-driven, red-green-refactor
refactor	New	Refactor this code, improve structure, clean up
diagnose	Preserved; frontmatter + standard added	Diagnose this, what's wrong with X, debug this

Key constraints per skill:

• implement-feature: must start from a linked issue with an EARS spec (checks docs/issues/ in the file-based phase, Gitea MCP when configured); flags if none exists; no unrequested abstractions; updates docs/spec/ as part of implementation if behaviour changes; calls tdd as its implementation methodology
• tdd: composable and separate from implement-feature so TDD can be used outside full feature implementation; red-green-refactor loop
• refactor: preserves all existing behaviour; documents what changed and why
• diagnose: preserved behavior; add frontmatter, authoring standard sections, and dead-reference cleanup

Implementation notes

Follow the per-skill workflow defined in docs/notes/skill-implementation-workflow.md.

Known upstream sources to review for this category:

• mattpocock/skills — original tdd and diagnose placeholders; review at current HEAD; record SHAs in source: for any adopted content
• bmad-method/bmad-method — BMAD developer role and implementation patterns; relevant for implement-feature and refactor

For new skills (implement-feature, refactor, write-docs): search for prior art in the above repos before writing from scratch.

Acceptance criteria

• All 4 SKILL.md files exist at .agents/skills/<skill-name>/SKILL.md; metadata.category: implement; authoring standard met (write-docs is in issue 0018 phase 2)
• Dead references removed from Pocock skills (tdd, diagnose)
• implement-feature checks for linked issue with EARS spec before proceeding; calls tdd by name
• source: fields populated for adopted upstream content
• Each skill has a co-located eval at .agents/evals/implement/<skill-name>/eval.yaml via write-eval
• install.sh deploys all 4 to ~/.agents/skills/
• HITL: human runs behavioral test per skill
• HITL: human reviews each SKILL.md and eval before committing
• Per-skill process followed for all 4 skills: source discovery (sub-agent) → source review with licence/security check (sub-agent) → conflict check against constitution + factory principles (sub-agent) → synthesis grill → co-write iteratively
• Trigger description for each skill tested against explicit, implicit, and negative queries before body written
• when: frontmatter field present in all SKILL.md files
• source: and references: fields correctly populated or absent
• eval.yaml for each skill contains all 5 required test types
• Body ≤500 lines for each skill
• write-docs confirmed removed from scope (implemented in issue 0018 phase 2)
• docs/spec/overview.md updated to reflect all 4 skills deployed

Blocked by

• 0016 (per-skill workflow)
• 0017 (write-eval)
• 0018 (write-skill)