Workflow required before generating, writing, or updating BAT (Blackbox API Testing) tests for a Mule app. Call use_skill as your FIRST action — before reading or writing any .dwl file — whenever the user asks to create, generate, add, write, refresh, extend, or fix BAT tests, a BAT suite, BDD API tests, black-box API tests, or Anypoint API Functional Monitoring tests for a deployed Mule HTTP API. Do not read the app source, open the existing suite, or author any .dwl yourself and attempt the task in one turn — even a targeted single-test change like 'add a 401 test' or 'fix the orders happy-path test' requires loading this skill first. Covers generating a suite from app source (OpenAPI + Mule XML), extending an existing hand-written BAT baseline, and running the suite against the live endpoint. Not for MUnit (build-time, in-process, XML) — use the Mule developer workflow for that. When you call this skill, it must be the only tool call in that response.