Skill 04 — Change Executor

Purpose: Implement code changes according to the plan, using probe-first navigation and safe verification.

Protocols:

• •[[docs/PROTOCOLS/VAULT_PROBE]]
• •[[docs/PROTOCOLS/EVIDENCE]]
• •[[docs/PROTOCOLS/RUN_LOGGING]]
• •[[docs/PROTOCOLS/PATCH_GATE]]
• •[[docs/PROTOCOLS/CONTEXT_BUDGET]]

Tools:

• •[[tools/repl/README]] — patch-gated edits (generate + check + apply)

Inputs (from Orchestrator)

• •docs/tasks/<task_slug>.md (required)
• •docs/plans/<task_slug>.md (required)
• •Optional: “focus area” hints (folders/components)

Outputs (must write)

• •repo changes (tracked by git)
• •artifacts/changeset_summary.json
• •[[docs/skills/04_change_executor/SUMMARY]]

Run log (mandatory)

Create: artifacts/_runs/<timestamp>_04_change_executor/

Include:

• •COMMANDS.md (probe commands, build/test commands)
• •LOG.txt
• •optional: DIFF.patch

Steps

1. •Slice-read task + plan (no full-doc reads).
2. •Use probe to locate the exact implementation targets:
   • •search for symbols, routes, config keys
   • •open minimal slices to confirm
3. •Implement changes incrementally.
4. •After each major change, run the fastest available verification (typecheck/lint/test/build).
5. •Write artifacts/changeset_summary.json:
   • •task_slug
   • •files_changed
   • •summary
   • •verification (commands + results)
   • •risks
6. •Write SUMMARY.md with:
   • •what changed
   • •where (evidence pointers)
   • •what to run next (usually Test Runner)

Definition of Done

• • Code changes implement the plan steps or explicitly document deviations
• • Changes are grounded with evidence pointers
• • Verification commands were executed (or explicit evidence that none exist)
• • Required outputs exist