implement

Implement

Execute an implementation plan created by /create-plan. Read the plan thoroughly, execute each step in order, emit a structured trajectory for every phase boundary, and report on the completed work.

Version history (v1.3-v1.8): the emission discipline changed over several versions. Version 1.6 added typed flags (one Bash call per event, no temp file). Version 1.7 added the emit-time sequencing guard (exit 5) and the run-level --verify files reconciliation. Version 1.8 fixed --verify's blindness to bracketing defects (orphan wave_end reconciliation, out-of-bracket step_end detection, advisory flags for a wave_start missing its declared shape). The Trajectory emission contract below carries the authoritative invariants, restated in Phase 2, Phase 5, and the NEVER list. The full per-version changelog is in references/implement-details.md.

Trajectory emission contract

The trajectory (outputs/operations/implement/_trajectory_<run_id>.jsonl) is the input to /scrutinize trajectory:<run_id> audits (Agent-as-a-Judge, DevAI benchmark) and a verbatim audit record: emit through the helper only, never edit it. All emission is skipped under --no-trajectory. The invariants, enforced by the phases below and self-checked by --verify:

• Pairing. Every step_start has a matching step_end (same step number); step 0 (plan-load) is paired too. Every wave_start has a wave_end.
• Sequencing (sequential waves / no-wave runs). Emit each step_end before the next step_start; never open step N+1 while step N is open. The helper enforces this at emit time (v1.7). A step_start opened while another step is still open exits 5 and does not land. A step_end for an unopened step does the same. To clear it, emit the missing marker first, or open a parallel wave_start for legitimate interleaving. If work genuinely reorders, emit a deviation that records the swap (the M1 discipline). Emit a step-scoped deviation as well when a run defers a plan-declared terminal action. The final [0 0] push that a step's success criteria mandate is one such action. The same holds when a run reverses an approved decision mid-run, or diverges from explicit plan text at all. Even a trivial, functionally-identical substitution such as re-sourcing an import counts. A step_end note alone is not enough, because the structured trajectory must match the plan's Deviations section. Parallel-wave member steps may legitimately interleave inside their wave bracket, because an open parallel wave suspends the guard.
• Wave bracketing. wave_start precedes the wave's first step_start, and wave_end follows all member step_ends. wave_end.successes equals the count of bracketed step_end with status ok or deviation, not the declared membership. Once a run emits any wave event, EVERY step but step 0 belongs to a bracket, and every wave_start carries --step-count and --parallel/--no-parallel. --verify checks all three since v1.8 (an orphan wave_end no longer buys its successes claim a free pass).
• Literal paths. --file takes one literal path per real file touched: no globs, brace-shorthand, or count strings (the N1 discipline).
• Whole-wave deferral. A wave not executed at all emits no wave_start/wave_end; instead one wave-scoped deviation keyed to the wave's first step (--scope wave --wave N).