Conciseness

Efficient overall: it delegates the tour catalog, time-box rationale, and card template to the sibling skill instead of re-explaining them, and the mission-pattern table teaches by example rather than abstract prose. Not 5: the exploratory-testing ownership boundary is restated in nearly every section ('are owned by exploratory-testing', 'the tours reference in exploratory-testing', 'owned by that skill', 'the exploratory-testing charter-template reference'), which could be trimmed to a single Overview statement. Not 3: there is no concept explanation Claude already knows and no padding.

Actionability

Mostly executable guidance: three concrete example missions covering the three input types ('Explore the new promo-code apply flow at checkout...'), explicit counts ('3-7 areas per 90-min session'), a named defect format ('BUG-* format'), and specific card fields to add ('source artifact..., the target build / SHA, and an explicit out-of-scope list'). Not 5: the assembled output is never shown — the actual card format is only reachable by fetching the sibling skill's charter-template, so the author cannot verify the final artifact from this file alone.

Workflow Clarity

Clear four-step sequence with an explicit assembly step ('Assemble mission (Step 1), areas + time-box + suggested tours (Step 2), and deliverables (Step 3) into the card format') plus a pre-emission validation checklist — the Halt rules enumerate four do-not-emit conditions with error-recovery guidance ('multi-mission sessions get split', 'split into multiple charters', 'review the previous debrief first'). Not 4: validation is not implicit; the Halt rules are an explicit checklist with remediation for each failure mode.

Progressive Disclosure

Good structure: a ~100-line single file, well-organized sections, detail correctly delegated to the sibling skill rather than inlined, and a clearly labeled References section with the primary source URL. Not 5: the sibling-asset pointers are indirect ('Time-box lengths (60 / 90 / 120 min) and their rationale: exploratory-testing') — a one-hop reference into another skill whose asset then must be located, which is slightly less navigable than direct one-level-deep file references; no bundle files exist to give direct paths.

Specificity

Lists multiple concrete actions with comprehensive coverage of the authoring workflow: 'frames the one-sentence mission, scopes 3-7 areas, picks a 60 / 90 / 120 min time-box, suggests tours, and wires the PROOF debrief deliverables' — each step is named with concrete parameters, and the closing sentence explicitly bounds the scope ('Authors the charter only'). Not 4: there are no coverage gaps; every phase of charter authoring is enumerated with specifics.

Completeness

Explicitly answers both questions: the 'what' is 'turns a feature spec, risk area, or bug cluster into a session-based exploratory testing charter', and the 'when' is an explicit clause with concrete triggers: 'Use when a feature has too many unknowns to script (new feature / refactor blast-radius / bug cluster) and a session-based exploration is the right approach.' Not 4: the when-clause is not merely present but specific, listing three concrete triggering situations.

Trigger Term Quality

Good keyword coverage: 'exploratory testing', 'session-based exploratory testing charter', 'SBTM', 'feature spec', 'risk area', 'bug cluster', 'refactor blast-radius' are phrases a practitioner would naturally say. Not 5: a few natural synonyms a user might type are absent (e.g. 'test charter', 'test session', 'ad hoc exploration'), so coverage is good but not exhaustive. Not 3: far more than 'some relevant keywords' — the domain vocabulary including the SBTM acronym and its expansion is present.

Distinctiveness Conflict Risk

Clear niche with distinct triggers (SBTM charter authoring) and minimal conflict risk: it explicitly separates itself from the closest sibling — 'Authors the charter only: the ready-to-fill charter card, session vocabulary, debrief template, and session review live in the exploratory-testing skill this workflow composes with.' Not 4: it doesn't just reduce overlap risk, it actively resolves the one real overlap (the exploratory-testing skill) by naming what it does not own.