What problem does it solve? Writing end-to-end tests for analytics metrics requires seeding bronze warehouse data, running dbt silver and gold models, and asserting API responses — a complex, error-prone process. This Skill scaffolds and validates the metric spec pair (a <name>.test.yaml fixture plus a test_<name>.py module) so the full bronze → silver → gold → analytics path is tested against a compose test-stand instance. ## Core Features & Use Cases - Spec scaffolding: Create a new <class>/<name>.test.yaml fixture with the required schemas and templates via /metric-test create <name> --metric <key> --tables <t1,t2>. - Offline validation: Resolve $ref references, schema-validate bronze records, and lint the pytest module without needing a running stand via /metric-test validate <path>. - Assertion guidance: Covers the assertion helpers (row/equals/contains, one/some over a view, approx), account bindings, identity aliases, duplicate-row dedup cases, and date-window boundary test design. - Use Case: When asked to "write a test for the emails-sent metric", the Skill produces the fixture seeding M365 bronze rows (including a re-sync duplicate) and a pytest module asserting collab.emails_sent period and peer values through POST /v1/metric-results. ## Quick Start Ask the assistant to write a test for a specific metric, for example: "Create a metric test for collab.emails_sent seeding m365 email activity rows."