ElevenLabs, Vapi, Bland
- Workflows layer on top of a base agent. Composition is a feature you configure, not the unit you build from.
- Integrations are yours to wire and maintain — the PMS connection, the vendor dispatch API, the SMS gateway, the auth, the retries.
- Test coverage is on you. Emergency triage is a prompt instruction, not a sub-agent with its own latency budget and test suite.