Conciseness

The body is mostly efficient process detail Claude could not infer, but the honesty rule is restated at least six times ("A checked item without proof is a lie", "An [x] without Actual output is a lie", "Marked [x] but has no Actual output → LIE. Go back.", plus the Anti-Patterns and Honesty Checklist sections), and the "If it fails: Stop. Fix. Re-run." recovery instruction is repeated after nearly every gate. Baseline and checklist-entry templates in §1c/§2e/§3e also duplicate the fuller templates in references/checklist-templates.md, whose own header says "Keep the SKILL.md procedure lean". Not 2 because no section explains background concepts or pads with filler — every section carries skill-specific instruction; not 4 because the rule repetition and template duplication are more than minor trimmable instances.

Actionability

Guidance is fully executable: exact checklist path (`.context/plans/<plan-slug>/CHECKLIST.md`), a fixed status vocabulary (PENDING/IN_PROGRESS/VALIDATED/BLOCKED), copy-paste commands (`grep -n "\[ \|IN_PROGRESS\|BLOCKED" CHECKLIST.md`), a concrete git commit template with evidence lines, and a real worked example in references/checklist-templates.md. Not 4: the placeholder gates (`<typecheck> && <build> && <test> && <lint>`) are not a gap — §1b explicitly mandates discovering the project's real commands from AGENTS.md, package.json, or CI config, which is justified flexibility for a project-agnostic skill.

Workflow Clarity

The 8-step workflow is clearly sequenced with explicit validation checkpoints at every level — quick gate after 1-3 file ops, full gate at task end, phase gate suite, domain invariant, regression diff against a recorded baseline, final gates, and a checklist completeness audit — each with an explicit feedback loop ("If it fails: Stop. Fix the issue. Re-run the command... Do not proceed to the next task until this passes"). Divergence handling and between-phase dependency rules close the remaining gaps. This is exactly the anchor-5 pattern; not 4 because checkpoints and error-recovery loops are explicit at every stage rather than mostly present.

Progressive Disclosure

The bundle has one reference file (references/checklist-templates.md, verified to exist) referenced one level deep and clearly signaled twice in the body ("See `references/checklist-templates.md` for the full CHECKLIST.md template and a worked example from a real phased run") plus a References section. Not 5 because template content that belongs solely in the reference file is inlined in SKILL.md (§1c baseline template, §2e checklist entry, §3e phase checklist) duplicating the reference's fuller templates; not 3 because references are clearly signaled and easy to navigate, which anchor 3 says they are not.

Specificity

Multiple concrete actions with comprehensive coverage: "Every task is pre-flighted, worked, validated with proof, and checked off", "Every phase is validated as a whole", and "If proof is missing, the agent goes back" — task-level, phase-level, and failure-recovery behavior are all named. Not 4: there are no coverage gaps; the description enumerates the full execute-verify-report loop rather than several actions with minor ones missing. Third-person voice is used throughout ("the agent goes back"), so no voice penalty applies.

Completeness

Explicitly answers both questions: what — "Execute an implementation plan with rigorous checklist-driven verification" with the task/phase/validation mechanics spelled out; when — an explicit "Triggers:" clause with nine concrete phrases plus a negative boundary ("Do NOT use for plans that have not been reviewed"). Not 4: the 'when' is not merely present but enumerated with concrete trigger phrases and an exclusion, exactly the anchor-5 example pattern.

Trigger Term Quality

Nine natural user phrasings are listed as triggers — 'implement this plan', 'execute the plan', 'start working on the plan', 'do the plan', 'carry out the phases', 'run the plan', 'work through the plan', 'carry out this plan', 'begin implementation' — covering the synonyms a user would naturally say when asking for this skill. Not 4: no common natural variation is missing; the coverage matches anchor 5's comprehensiveness (file extensions are irrelevant here since the skill triggers on user intent, not file types).

Distinctiveness Conflict Risk

Clear niche — executing an already-reviewed plan — with action-specific triggers ('implement this plan', 'execute the plan') that differ from what a user would say to the neighboring plan-create/plan-review skills. The explicit disambiguation "Do NOT use for plans that have not been reviewed — use plan-review first" resolves the closest competing skill directly. Not 4: boundary guidance is explicit rather than leaving minor overlap risk with closely related skills.