Conciseness

The body is mostly efficient procedural instruction, but there is systematic duplication: the '## Arness is not configured' message appears verbatim in both Prerequisites and Step 1, the parenthetical 'passing the model from .arness/agent-models/code.md as the model parameter (see ${CLAUDE_PLUGIN_ROOT}/skills/arn-code-ensure-config/references/ensure-config.md "Dispatch convention" for fallback)' is repeated three times (Steps 3.5, 4, and 5b fallback), and the Error Handling section restates cases already covered in-line. The opening drift-rationale paragraph ('Specs may have been written days or weeks before being planned. The codebase moves in the meantime...') is mild padding.

Actionability

The guidance is copy-paste ready: exact output paths ('<plans-dir>/PLAN_PREVIEW_<spec-name>.md'), verbatim agent context blocks with full content templates, exact user-facing messages, and fully specified AskUserQuestion prompts with enumerated options (e.g., 'Yes, upgrade all complex phases' / 'No, keep configured tier'). All common cases — spec found/not found, drift severities, resume failure, existing PLAN_PREVIEW — have concrete handling.

Workflow Clarity

The sequence (Steps 1→6 with 3.5, 5a, 5b) is explicit with validation checkpoints throughout: drift detection with severity-based branching before planning, an approval gate before proceeding, and a feedback loop (present → revise via agent resume → re-present) with a fallback on resume failure. Error paths for every failure mode (missing config, no specs, agent crash, file not written, user cancel) are enumerated.

Progressive Disclosure

No bundle files exist (no references/, scripts/, or assets/), so the skill is a single self-contained SKILL.md with clear section headers, and its cross-plugin references (ensure-config.md, arn-code-feature-planner.md, preferences-schema.md) are clearly signaled with paths one level deep. The gap is that Step 5a (~55 lines) inlines the two-tier preference lookup and YAML write-back logic that would fit a reference file, making the body longer than an ideal overview.

Specificity

The description lists multiple concrete actions with comprehensive coverage of the skill's behavior: 'invokes the arn-code-feature-planner agent to generate the plan, presents it for review, and iterates on user feedback until approved. Produces a PLAN_PREVIEW file that feeds into /arn-code-save-plan.' No vague language, and the pipeline linkage to save-plan is stated explicitly.

Completeness

Both 'what' and 'when' are explicit: 'This skill should be used when the user says [extensive trigger list]... or wants to generate an implementation plan from a Arness specification' answers when with concrete trigger phrases, and the following sentences answer what (invoke planner agent, present for review, iterate to approval, produce PLAN_PREVIEW).

Trigger Term Quality

Trigger coverage is comprehensive, spanning command forms ('arness code plan', 'arn-code-plan', 'arness code plan FEATURE_X'), natural phrases ('write a plan', 'create plan', 'implementation plan', 'generate plan', 'make a plan'), and domain variants ('plan the spec', 'plan from spec', 'plan feature', 'plan bugfix', 'plan the bugfix'). All the phrasings a user would naturally say are represented.

Distinctiveness Conflict Risk

The skill's niche is clear ('generate an implementation plan from a Arness specification' with Arness-specific triggers like 'arness code plan'), but the generic phrases 'write a plan', 'create plan', 'make a plan', and 'generate plan' would match virtually any planning request regardless of Arness context. This creates overlap risk not just with closely related pipeline skills but with any planning-adjacent intent, matching the anchor 'somewhat specific but could still overlap with similar skills' rather than the minor-overlap anchor above it.