---
title: "Create a new MCP server instance"
method: POST
path: "/api/v3.1/mcp/servers/{serverId}/instances"
tags: ["MCP", "Servers", "Instances"]
---

# Create a new MCP server instance

`POST /api/v3.1/mcp/servers/{serverId}/instances`

Creates a new instance for a Model Control Protocol (MCP) server. This endpoint validates that the user has connected accounts for all auth configurations associated with the MCP server before creating the instance.

## Path parameters

- `serverId` string, required — UUID of the MCP server to create an instance for

## Request body

- object — Parameters for creating a new MCP server instance
  - `user_id` string, required — The user ID (entity ID) that will be used as both the user identifier and instance ID

## Response `201`

Successfully created MCP server instance. Returns the created instance details.

- object — MCP server instance details
  - `id` string, required — UUID of the instance record
  - `instance_id` string, required — The instance identifier (same as the user_id)
  - `mcp_server_id` string, required — UUID of the parent MCP server
  - `created_at` string, required — Date and time when this instance was created
  - `updated_at` string, required — Date and time when this instance was last modified

## Other responses

- `400` — Bad request. The request parameters may be invalid.
- `401` — Unauthorized. Authentication is required or the provided credentials are invalid.
- `403` — Forbidden. The user does not have connected accounts for all required auth configurations.
- `404` — MCP server not found. No server with the specified ID exists.
- `409` — Conflict. An instance with this ID already exists for the server.
- `500` — Internal server error. An unexpected error occurred while processing the request.

---

[API](https://skmtc.net/composiohq/apis/composio-platform-api-v3-1.md) · [All operations](https://skmtc.net/composiohq/apis/composio-platform-api-v3-1/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/composiohq/composio-platform-api-v3-1/versions/4239836857f8/schema)