Mocks only answer what you wrote. StateWeave gives your agent working copies of Slack, Gmail, Salesforce, Shopify, Zendesk and more apps: same APIs, MCP servers, web UIs and errors as the real thing, filled with your data or a company generated from one sentence. Inject real outages and failures seen live on those services, grade every run, and compare agent versions. One install and Claude Code, Codex or Cursor runs the tests, reads what broke and fixes it. Free to start.