Mock all tools in a simulation test

A simulation test that hits live tools is not a test, it is a flaky integration run. Mock every tool the agent can reach so a failure means the agent behaved wrong, not that a dependency moved.

Host https://api.elevenlabs.io, header xi-api-key: $API_KEY. The engineer supplies $API_KEY, $AGENT_ID, $BRANCH_ID.

The one mistake that breaks almost every mock

Mocks match on tool ID, never on tool name. An override keyed by a name, or by an ID that is not on this agent, is silently ignored. The tool then runs unmocked and you see this in the transcript:

Error: no mock matched for tool 'open_support_form'

That message means "your key did not match", not "mocking is off". It is the single largest cause of red simulation suites.

Two ways to get the key wrong, both common: