> ## Documentation Index > Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt > Use this file to discover all available pages before exploring further. # Update an MCP server > Changes an MCP server's settings. A field left out stays as it is. `auth` is replaced whole, `tools: []` exposes every tool, and `static_headers: {}` clears the headers. The instance must be `ready`; otherwise the request answers `409`. ## OpenAPI ````yaml /openapi/source/external/agent-gateway/agent-gateway.json patch /agent_gateways/{instance_id}/mcp_servers/{server_id} openapi: 3.1.0 info: version: 1.0.0 title: Telnyx API x-latency-category: interactive x-endpoint-cost: light description: >- Agent Gateway authenticates, authorizes, and audits the requests agents send to models, tools, and other agents. Each gateway runs as a dedicated instance on the account's [*Network*](https://developers.telnyx.com/docs/network/overview). This API creates, lists, and deletes instances, and manages the keys, teams, spend logs, MCP servers, APIs, tool permissions, and guardrails on them. Each instance serves an OpenAI-compatible API at its `gateway_url`. servers: - url: https://api.telnyx.com/v2 description: Telnyx API v2 security: - bearerAuth: [] tags: - name: Agent Gateways description: Create, list, retrieve, and delete Agent Gateway instances. - name: Agent Gateway Keys description: Keys on an instance. - name: Agent Gateway Teams description: 'Teams on an instance: shared model lists, budgets, and rate limits.' - name: Agent Gateway Spend Logs description: The requests an instance served, with their cost. - name: Agent Gateway MCP Servers description: MCP servers on an instance, served to agents at one MCP endpoint. - name: Agent Gateway APIs description: REST APIs on an instance, served to agents as tools. - name: Agent Gateway Tool Permissions description: The MCP servers and tools a key or team may use. - name: Agent Gateway Guardrails description: Checks an instance runs on model and tool requests. - name: Agent Gateway Policies description: Named sets of guardrails an instance applies to requests. - name: Agent Gateway Policy Attachments description: Where an instance applies each policy. paths: /agent_gateways/{instance_id}/mcp_servers/{server_id}: patch: tags: - Agent Gateway MCP Servers summary: Update an MCP server description: >- Changes an MCP server's settings. A field left out stays as it is. `auth` is replaced whole, `tools: []` exposes every tool, and `static_headers: {}` clears the headers. The instance must be `ready`; otherwise the request answers `409`. operationId: UpdateAgentGatewayMcpServer parameters: - name: instance_id in: path required: true description: The Agent Gateway's `id`. schema: type: string format: uuid example: 32ce035d-3165-4031-b1a7-a7c0c259590a - name: server_id in: path required: true description: The MCP server's `id`. schema: type: string format: uuid example: 88d5a97b-4080-4855-8bac-a39811b1dc24 requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/AgentGatewayMcpServerUpdate' examples: tools: summary: Expose two tools value: tools: - get_order - create_ticket responses: '200': description: The updated MCP server content: application/json: schema: $ref: '#/components/schemas/AgentGatewayMcpServerResponse' example: data: id: 88d5a97b-4080-4855-8bac-a39811b1dc24 name: orders url: http://10.40.3.7:9000/mcp transport: http auth: type: api_key tools: - get_order - create_ticket static_headers: X-Env: prod forwarded_headers: - X-Request-Id open_to_every_key: false created_at: '2026-10-28T16:50:43.184000Z' updated_at: '2026-10-28T16:50:43.184000Z' '400': description: A name the instance already uses content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '10012' title: Duplicate resource detail: Resource is a duplicate. meta: url: https://developers.telnyx.com/docs/overview/errors/10012 source: pointer: /name '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '10009' title: Authentication failed detail: >- The required authentication headers were either invalid or not included in the request. meta: url: https://developers.telnyx.com/docs/overview/errors/10009 '404': description: Not found content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '10005' title: Resource not found detail: The requested resource or URL could not be found. meta: url: https://developers.telnyx.com/docs/overview/errors/10005 '409': description: The instance is not `ready` content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '99901' title: Instance not ready detail: The instance is not ready; its engine is not running. '422': description: A field fails validation content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '10027' title: Unprocessable Entity detail: The value is invalid. meta: url: https://developers.telnyx.com/docs/overview/errors/10027 source: pointer: /transport '502': description: The instance's engine did not answer content: application/json: schema: $ref: '#/components/schemas/TelnyxErrors' example: errors: - code: '99903' title: Engine unavailable detail: The instance's engine did not answer; try again shortly. components: schemas: AgentGatewayMcpServerUpdate: type: object additionalProperties: false properties: name: type: string pattern: ^[A-Za-z0-9_.]{1,100}$ description: >- A name for the server, unique on the instance across MCP servers and APIs, regardless of case. Letters, digits, `_`, and `.`. The gateway prefixes the server's tools with it and a hyphen. url: type: string description: The server's MCP endpoint, `http` or `https`. transport: type: string enum: - http - sse default: http description: '`http` for Streamable HTTP, or `sse` for Server-Sent Events.' auth: oneOf: - $ref: '#/components/schemas/AgentGatewayNoAuth' - $ref: '#/components/schemas/AgentGatewayStaticAuth' - $ref: '#/components/schemas/AgentGatewayOAuthClientCredentials' - $ref: '#/components/schemas/AgentGatewayPassthroughAuth' - $ref: '#/components/schemas/AgentGatewayAwsSigV4Auth' description: >- How the gateway authenticates to the server. Replaced whole on an update; `{"type": "none"}` removes the credential. tools: type: array items: type: string description: >- The tools the server exposes to every key, by name. `[]` exposes every tool. static_headers: type: object additionalProperties: type: string description: Headers sent on every request. forwarded_headers: type: array items: type: string maxItems: 32 description: Headers copied from the agent's request, by name. open_to_every_key: type: boolean default: false description: >- `true` lets every key on the instance use the server, granted or not. description: The fields to change. A field left out stays as it is. AgentGatewayMcpServerResponse: type: object required: - data properties: data: $ref: '#/components/schemas/AgentGatewayMcpServer' TelnyxErrors: type: object properties: errors: type: array items: $ref: '#/components/schemas/TelnyxError' AgentGatewayNoAuth: type: object title: No authentication description: The gateway sends no credential. properties: type: type: string const: none AgentGatewayStaticAuth: type: object title: API key required: - type - value description: >- A static credential the gateway sends on every request. Write-only: responses show its `type` only. properties: type: type: string enum: - api_key - bearer_token - basic - token - authorization description: >- How the credential is sent: `api_key` as `X-API-Key: `, `bearer_token` as `Authorization: Bearer `, `basic` as `Authorization: Basic ` with `value` in the form `user:password`, `token` as `Authorization: token `, and `authorization` as `Authorization: `. value: type: string writeOnly: true description: The credential. header: type: - string - 'null' description: A header name that replaces `X-API-Key` or `Authorization`. AgentGatewayOAuthClientCredentials: type: object title: OAuth client credentials required: - type - token_url - client_id - client_secret description: >- The gateway gets its own access token with the `client_credentials` grant and sends it as a bearer token on every request, renewing it before it expires. The client ID and secret are write-only. properties: type: type: string const: oauth_client_credentials token_url: type: string description: The OAuth provider's token endpoint. client_id: type: string writeOnly: true client_secret: type: string writeOnly: true credentials_in: type: string enum: - body - basic default: body description: >- Whether the client ID and secret go in the token request's body or as HTTP Basic authentication. scopes: type: array items: type: string description: The scopes to request. audience: type: - string - 'null' description: The token's audience, sent in the token request. resource: type: - string - 'null' description: The resource the token is for, sent in the token request. AgentGatewayPassthroughAuth: type: object title: Token passthrough description: >- The gateway forwards the agent's own `Authorization` header to the server unchanged. properties: type: type: string const: passthrough AgentGatewayAwsSigV4Auth: type: object title: AWS Signature Version 4 required: - type - region description: >- The gateway signs each request with AWS Signature Version 4. Without keys or a role, it uses the instance's own AWS identity. Keys are write-only. properties: type: type: string const: aws_sigv4 region: type: string description: The AWS region to sign for. service: type: string default: bedrock-agentcore description: The AWS service to sign for. access_key_id: type: - string - 'null' writeOnly: true secret_access_key: type: - string - 'null' writeOnly: true session_token: type: - string - 'null' writeOnly: true role_name: type: - string - 'null' description: The ARN of a role for the gateway to assume. AgentGatewayMcpServer: type: object required: - id - name - url - transport - auth - tools - static_headers - forwarded_headers - open_to_every_key - created_at - updated_at properties: id: type: string format: uuid description: Identifies the server. name: type: string description: >- A name for the server, unique on the instance across MCP servers and APIs, regardless of case. Letters, digits, `_`, and `.`. The gateway prefixes the server's tools with it and a hyphen. url: type: string description: The server's MCP endpoint. transport: type: string enum: - http - sse description: '`http` for Streamable HTTP, or `sse` for Server-Sent Events.' auth: $ref: '#/components/schemas/AgentGatewayShownAuth' tools: type: array items: type: string description: >- The tools the server exposes to every key, by name. `[]` exposes every tool. static_headers: type: object additionalProperties: type: string description: Headers sent on every request. forwarded_headers: type: array items: type: string maxItems: 32 description: Headers copied from the agent's request, by name. open_to_every_key: type: boolean default: false description: >- `true` lets every key on the instance use the server, granted or not. created_at: type: - string - 'null' format: date-time updated_at: type: - string - 'null' format: date-time TelnyxError: type: object properties: code: type: string title: type: string detail: type: string source: type: object properties: pointer: type: string parameter: type: string meta: type: object properties: url: type: string AgentGatewayShownAuth: type: object description: >- The server's outbound authentication method. Credentials are never returned. properties: type: type: string description: The method's `type`. required: - type securitySchemes: bearerAuth: type: http scheme: bearer description: Telnyx API key ````