# POST /v1/convai/mcp-servers/{mcp_server_id}/tool-configs (ElevenLabs API)
Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-09-03

> Create Mcp Tool Configuration Override

## Critical Gotchas
* Authentication uses the non-standard `xi-api-key` header, not `Authorization: Bearer`. Sending a Bearer token returns HTTP 401.
* Text-to-speech responses are raw binary audio, not JSON. Write the body to a file (`--output speech.mp3`) rather than parsing it.

## cURL
curl -X POST 'https://api.elevenlabs.io/v1/convai/mcp-servers/mcp-server-id/tool-configs?environment=production' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"force_pre_tool_speech":true,"pre_tool_speech":"auto"}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| mcp_server_id | path | string | Yes | ID of the MCP Server. |
| tool_name | body | string | Yes | The name of the MCP tool |
| environment | query | string | No | Environment whose values are used whe... |

## Response (200 OK)
{"id":"string","config":{"approval_policy":"require_approval_all","tool_approval_hashes":[]}}

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