Quickstart
Make your first API call and run your first conversation in under 5 minutes.
Authentication
Learn how to create API keys and authenticate every request.
Build an assistant
Create your first AI assistant with a knowledge base and custom tools.
API Reference
Explore all endpoints, parameters, and response shapes.
What you can build
Feather’s platform API covers the full stack of customer experience automation:Assistants
Create versioned assistants with system prompts, knowledge bases, tools, and policies.
Knowledge bases
Ingest documents from files, URLs, Notion, Google Drive, and S3 — then search semantically.
Multi-channel
Handle conversations over chat, voice, SMS, and email in a unified session model.
Voice calls
Build outbound and inbound voice assistants with STT/TTS, warm transfers, and voicemail detection.
Integrations
Connect Slack, Notion, Google Drive, and custom MCP servers to give assistants real-world tools.
Evaluations
Run simulation suites and model-judge evaluators to measure and improve assistant quality.
How it works
1
Authenticate
Create an API key in your organization settings. Include it as
x-api-key: <key> on every request.2
Create an assistant
POST /v1/assistants with a name and system prompt, then activate a revision. Add knowledge bases and custom tools to power its responses.3
Start a conversation
POST /v1/conversations to open a session, then POST /v1/conversations/{id}/turns to send messages. Stream responses in real time with the /turns/stream endpoint.4
Monitor and improve
Use built-in analytics, evaluators, and knowledge-gap detection to continuously improve your assistants over time.
Base URL
All API requests target the sandbox environment:Contact Feather to provision your production environment credentials. All examples in these docs use the sandbox base URL.