craft:implementation

Preamble (always runs — non-overridable)

1. Manifest read (lint if standalone). Probe gates: gates.part (else: repo test runner over touched files; else fall back to gates.phase per part — slower, never gateless) and gates.phase (else: repo validate/check/test script; if nothing exists, REFUSE to run this phase — a workflow without any gate is not this workflow).
2. The plan must exist and pass plan-lint.sh (re-run it; cheap) — unless no plan exists at <plan-dir>/<slug>.md and the run record holds a NO-OP(planning): line (grep -F 'NO-OP(planning):' on the ledger path that run-ledger.sh locate or the reorient block yields). Then the phase is a no-op: spawn nothing, append no PART line, skip Procedure 1–2, and run gates.phase once in-session (the Procedure 3 gate — the phase is never gateless, even here; a manifest override: cannot skip it). On green, one run-ledger.sh append <run-id> implementation call carries NO-OP(implementation): no plan parts — planning recorded NO-OP(planning), GATE(implementation): green and PHASE-DONE(implementation): no-op — no plan parts. On red, append the NO-OP line and GATE(implementation): red without PHASE-DONE, fix and commit as Procedure 3 states, re-run the gate, and append its result: PHASE-DONE lands only with a green gate, so a rebuild never reads a red phase as closed. A plan file that exists next to a NO-OP(planning): line is a contradiction: escalate { implementation, reason, ≤3 options }, never guess which wins. No plan and no NO-OP(planning): line (standalone included): refuse, as before.
3. Memory read/write surface (advisory). READS: gate-cmd entry for this repo as an advisory hint — if a gate command was previously recorded, skip re-discovery but still run it (the gate is sacred; the hint only saves the probe, never the execution). A miss falls through to the full gate probe. WRITES (appended to the run record as produced; saved to the store once at Done): the gate/test command discovered this run — stored as the BARE command only, with any leading env/secret assignment prefix stripped (never TOKEN=… npm test or a command carrying a credential), since the store is committed; per-part size + pass/blocked outcome for each implemented part.

Procedure (default body — a manifest override: replaces everything below)

1. Execute parts top-to-bottom, one craft:part-implementer per part, sequential — never two agents writing one tree concurrently. Each spawn carries: the working directory; the plan path (the agent reads the part there) + the part's ### Context block verbatim AND any load-bearing deltas — hand the pre-chew over so the agent never re-greps the codebase, but do NOT re-transcribe the whole committed part; the design doc path; the resolved part gate; the commit message from the plan; global + implementation-phase context: files verbatim.
2. After each agent returns, verify before launching the next: the commit exists and matches the part promise (git log, git show --stat). Once verified, in that same verification's Bash call or the very next one, append PART(<n>): <sha> size=<size> outcome=<pass|blocked> via "${CRAFT_ROOT:-${CLAUDE_PLUGIN_ROOT}}/scripts/run-ledger.sh" append <run-id> implementation — <size> is one kebab-case shape label for the part (e.g. pure-module, docs-prose), ? when unknown; a label with a space breaks the token. A landed commit found without a PART line on resume is verified first, then gets its line. Spot-check conventions on the diff. Every IMPACT( line and deferred observation in the handback gets its verdict under the run skill invariant Impacts: fold or defer at discovery before the next part spawns. Failed/blocked part → fix in-session or escalate with the agent's options; dead agent → fresh respawn from the plan part (artifact handoff); never relaunch blindly.
3. Phase-boundary gate: after the LAST part, run gates.phase once in-session. It MUST be green before the review phase — fix and commit anything it surfaces (fix(<scope>): close gate gap after part N).