Conciseness

The body is dense with actionable templates and commands rather than concept explanations, but it is noticeably repetitive: the 'no suggestions' rule is restated in 'CRITICAL: Documentarian Only', agent prompt templates, the 'Critical Reminders' section, and 'NO_OPINIONS' in Success Criteria, and the per-phase checkpoints are largely restated later. It could be tightened considerably without losing information, matching 'mostly efficient but includes some unnecessary explanation or could be tightened' rather than the noticeably padded level 2.

Actionability

Provides copy-paste-ready bash (the PRP store resolver, metadata gathering), concrete agent prompt templates, a query-classification table, and usage examples for every flag. It falls short of 5 because much guidance is template prose with placeholders (e.g. 'Wait for ALL agents', the output template) rather than executable steps for how agents are actually spawned, leaving minor gaps.

Workflow Clarity

A clear six-phase sequence (PARSE→DECOMPOSE→EXPLORE→SYNTHESIZE→DOCUMENT→OUTPUT) with an explicit checkbox checkpoint after every phase, gap identification, and conditional handling ('if --follow-up', 'if applicable' permalinks). It does not reach 5 because there are no error-recovery feedback loops (e.g. what to do when agents return conflicting or empty findings, or a mentioned file doesn't exist).

Progressive Disclosure

No bundle files exist (no references/, scripts/, or assets/), and the ~390-line body inlines content that belongs in separate files: the full research-document template, the PRP store-resolver bash script, and the output template would naturally live as references/scripts. Section structure is good, but this matches 'some structure; content that should be separate is inline' rather than a well-split overview with one-level-deep references.

Specificity

'Research codebase questions using parallel agents - documents what exists, not what should change' names the domain and one or two concrete behaviors (research questions via parallel agents, document what exists), but does not enumerate several specific actions, matching 'names domain and 1-2 concrete actions, but not comprehensive' rather than level 4's list of several specific actions.

Completeness

Both parts are explicit and concrete: the 'what' ('Research codebase questions using parallel agents - documents what exists, not what should change') and the 'when' ('Use when the user asks how the codebase works, where something lives, or invokes $prp-codebase-question'), mirroring the anchor-5 pattern of a clear what plus explicit trigger phrases.

Trigger Term Quality

Natural user phrases are present: 'how the codebase works', 'where something lives', plus the explicit '$prp-codebase-question' invocation. This is good keyword coverage but misses common variations users would say ('explain', 'trace', 'find', 'architecture'), so it sits at level 4 rather than the comprehensive synonym coverage of level 5.

Distinctiveness Conflict Risk

The read-only 'documents what exists, not what should change' stance clearly distinguishes it from code-review/refactoring skills, and it has its own command trigger. Minor overlap risk remains with generic code-exploration or documentation skills, placing it at 'mostly distinct' rather than the minimal-conflict niche of level 5.