MCP (AI agents)

Revox exposes a generic MCP server that mirrors the full REST API as MCP tools. Use it to place calls, manage assistants, run campaigns, and more.

MCP server URL

Use the /mcp endpoint (streamable HTTP) with your favorite tools — e.g. OpenClaw, Cursor, Postman, or any MCP client.

MCP endpoint: https://www.getrevox.com/api/mcp-servers/generic/mcp

Authentication

Use your Revox API key (same as the REST API). Send it as a Bearer token on every MCP request.

• Header: Authorization: Bearer YOUR_API_KEY
• Get your API key: Dashboard → API Keys

Keep your API key secure. Do not expose it in client-side code or public repos.

Tools (overview)

The server exposes the same capabilities as the REST API, as MCP tools. Main tools for voice workflows:

Tool	Description
revox_create_campaign	Create a campaign (assistant, contact list, schedule). The primary way to launch bulk outbound calls.
revox_get_campaign	Get campaign by ID — status, progress, and analytics.
revox_list_campaigns	List campaigns (paginated).
revox_make_call	Place a single call (phone number, custom prompt). Voice is auto-selected from the phone number’s country; override with voice_provider/voice_id.
revox_get_call	Get call by ID. Use to poll once, or see revox_wait_for_call for periodic updates.
revox_wait_for_call	Poll a call by ID every few seconds; receive status via notifications/message until complete.
revox_get_call_history	List calls (paginated).
revox_list_assistants	List assistants.
revox_get_assistant	Get assistant by ID.
revox_create_assistant	Create an assistant (name, prompt, optional voice for accent/language).
revox_auth_status	Check if the API key is valid.

Additional tools cover phone numbers, voices, users, billing, and Nango integrations.

Voice selection

Automatic voice selection (calls)

When you place a call with revox_make_call, the voice is automatically selected based on the target phone number’s country. For example, calling a +33… (France) number picks a French voice, +49… (Germany) picks German, and so on. No extra parameters are needed — just pass the phone_number and prompt.

You can override this by explicitly passing voice_provider and voice_id.

Manual voice selection (assistants)

When you create an assistant with revox_create_assistant, set voice_provider and voice_id so the voice matches the language of your prompt (e.g. French prompt → French voice). If you omit them, the default is an American English voice.

1. Call revox_list_voices to get available voices; filter by language (e.g. "fr" for French).
2. In revox_create_assistant, pass voice_provider (e.g. "cartesia") and voice_id (the ID from the list). Example for French: Cartesia voice ID a249eaff-1e96-4d2c-b23b-12efa4f66f41.
3. Use revox_update_assistant with voice_provider and voice_id to change an existing assistant’s voice. Tool names follow the pattern revox_<action>_<resource> (e.g. revox_create_campaign, revox_list_phone_numbers).

Call status (no webhooks in MCP)

MCP does not support server-initiated webhooks. After revox_make_call you get a call.id; to know when the call is done:

1. Poll: Call revox_get_call with that ID repeatedly until the call status indicates completion.
2. Periodic updates: Call revox_wait_for_call with the call ID. The server polls every few seconds (default 5), sends each status to the client via notifications/message, and returns the final call when the call completes (or on timeout/abort).
3. Revox webhooks: When placing a call with a custom assistant, you can set webhook_url on the assistant. Revox will HTTP POST to that URL when the call ends. Your own server can then notify the agent or user.

Example: place a call and get completion

1. Call revox_make_call with phone_number and prompt. The voice is automatically matched to the phone number’s country (e.g. a French number gets a French voice). To override, pass voice_provider and voice_id explicitly (use revox_list_voices to find IDs).
2. From the response, read call.id.
3. Either call revox_get_call with that id repeatedly until completed, or call revox_wait_for_call once to receive periodic status updates and the final result.
4. Use the call result (e.g. transcript, recording) as needed.

REST API reference

For request/response shapes and optional parameters, see the API Reference. The MCP tool inputs map to the same request bodies and query parameters — see Campaigns, Calls, Assistants, and Voices.