Conciseness

The body is short and almost entirely project-specific (source of truth, apm.yml integration, when the gate applies) with two compact commands; it assumes competence rather than explaining Schemathesis from scratch. It is not a 5 because a couple of rationale sentences ('O contrato precisa aguentar o que o spec permite', the one-line recap of what Schemathesis does) could be trimmed without losing guidance value.

Actionability

Two concrete, executable invocations are given ('apm run schemathesis --param spec=<caminho-ou-url-do-openapi>' and 'python3 -m schemathesis run <caminho-ou-url-do-openapi>') plus explicit do/don't guidance (point at the platform spec, don't invent one). It stops short of 5 because there is no guidance on locating the actual spec path/URL for the data platform and no example of expected output or common-case invocation.

Workflow Clarity

The single action is unambiguous — run Schemathesis against the platform's spec before declaring the task done — and the applicability condition (route/schema/status/OpenAPI changes vs. pure Python changes) is explicit. It is not a 5 because the failure path is only stated ('Falha dura') without a fix-and-retry loop telling the agent what to do when the run reports divergences.

Progressive Disclosure

Under 50 lines with no bundle files, organized into clear sections that point one level deep to well-signaled external docs ('docs/schemathesis.md', 'docs/regras-de-negocio.md', 'docs/qualidade-seguranca.md', 'scripts/agent_loop.py') and explicitly declines to duplicate them ('Não copie essa página'). This matches the rubric's exception for short, self-contained skills with well-organized sections.

Specificity

The description names the domain ('HTTP API, an OpenAPI spec, or routes covered by contract tests') and one concrete action ('Run Schemathesis against the spec before calling the task done'), matching the 'domain and 1-2 concrete actions, but not comprehensive' anchor. It is not a 4 because only a single capability is listed, not several specific actions.

Completeness

It explicitly answers both: what ('Run Schemathesis against the spec before calling the task done') and when ('Use when the task changes an HTTP API, an OpenAPI spec, or routes covered by contract tests'), with concrete trigger phrases — the exact pattern of the anchor-5 good example. Not a 4, because the 'when' clause is already explicit and specific rather than only improvable.

Trigger Term Quality

Natural trigger phrases users would say are present: 'changes an HTTP API', 'an OpenAPI spec', 'routes covered by contract tests'. Good keyword coverage, but common variations like 'endpoint', 'REST', or 'Swagger/OpenAPI definition' are missing, so it falls between the 3 and 5 anchors — closer to the 4 anchor's 'a few natural terms missing'.

Distinctiveness Conflict Risk

It occupies a clear niche (Schemathesis contract testing against the OpenAPI spec) with distinct triggers unlikely to fire for unrelated skills; the only conceivable overlap is with a generic 'testing' skill, which is minimal.