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MCP Servers

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Administrators can register external MCP servers that provide additional tools for agent chat sessions. Configured servers are injected into or offered to users during chat depending on the availability policy.

This is an admin-only feature accessible at Agents > Settings > Manage Agents > MCP Servers.

Add an MCP server

Navigate to Agents > Settings > Manage Agents > MCP Servers.
Click Add.
Fill in the configuration fields described below.
Click Save.

Identity

Field	Required	Description
`display_name`	Yes	Human-readable name shown to users in chat.
`slug`	Yes	URL-safe unique identifier, auto-generated from display name.
`description`	No	Brief summary of what the server provides.
`icon_url`	No	Emoji or image URL displayed alongside the server name.

Connection

Field	Required	Description
`url`	Yes	The MCP server endpoint URL.
`transport`	Yes	Transport protocol. `streamable_http` or `sse`.

Availability

Field	Required	Description
`enabled`	No	Master toggle. Disabled servers are hidden from non-admin users.
`availability`	Yes	Controls how the server appears in chat sessions. See Availability policies.
`model_intent`	No	When enabled, requires the model to describe each tool call's purpose in natural language, shown as a status label in the UI.
`forward_coder_headers`	No	When enabled, forwards Coder identity headers on every outgoing MCP request. See Coder identity headers.

Availability policies

Policy	Behavior
`force_on`	Always injected into every chat. Users cannot opt out.
`default_on`	Pre-selected in new chats. Users can opt out.
`default_off`	Available in the server list but users must opt in.

Authentication

Each MCP server uses one of five authentication modes. When you change the auth type, fields from the previous type are automatically cleared.

Secrets are never returned in API responses — boolean flags indicate whether a value is set.

None

No credentials are sent. Use this for servers that do not require authentication.

OAuth2

Per-user authorization. The administrator configures the OAuth2 provider, and each user independently completes the authorization flow.

Manual configuration — provide all three fields together:

Field	Description
`oauth2_client_id`	OAuth2 client ID.
`oauth2_auth_url`	Authorization endpoint URL.
`oauth2_token_url`	Token endpoint URL.

Optional fields:

Field	Description
`oauth2_client_secret`	OAuth2 client secret.
`oauth2_scopes`	Space-separated list of scopes.

Auto-discovery — leave oauth2_client_id, oauth2_auth_url, and oauth2_token_url empty. The server attempts discovery in this order:

RFC 9728 — Protected Resource Metadata
RFC 8414 — Authorization Server Metadata
RFC 7591 — Dynamic Client Registration

Users connect through a popup that redirects through the OAuth2 provider. Tokens are stored per-user and refreshed automatically. Users can disconnect via the UI or API to remove stored tokens.

API key

A static key sent as a header on every request.

Field	Required	Description
`api_key_header`	Yes	Header name (e.g., `Authorization`).
`api_key_value`	Yes	Secret value sent in the header.

Custom headers

Arbitrary key-value header pairs sent on every request. At least one header is required when this mode is selected.

User OIDC Identity

Forwards the calling user's OIDC access token (stored in user_links.oauth_access_token) to the MCP server as an Authorization: Bearer <token> header. The token is refreshed transparently before each request if it has expired or is close to expiring.

No admin-configurable fields. No per-user connect step.

Limitation: this auth mode only works for users who authenticated to Coder via OIDC. Users who logged in with password or GitHub will see requests sent without an authorization header, and the upstream MCP server is expected to respond with 401.

Tool governance

Control which tools from a server are available in chat:

Field	Description
`tool_allow_list`	If non-empty, only the listed tool names are exposed. An empty list allows all tools.
`tool_deny_list`	Listed tool names are always blocked, even if they appear in the allow list.

Coder identity headers

MCP servers configured with forward_coder_headers = true receive the following identity headers on every outgoing request, alongside the auth header for the configured auth_type:

Header	Description
`X-Coder-Owner-Id`	Coder user who owns the chat that issued the tool call.
`X-Coder-Chat-Id`	Top-level (parent) chat ID. For root chats this is the chat's own ID; for subchats it is the parent chat ID.
`X-Coder-Subchat-Id`	Subchat ID. Only present when the request originates from a child chat.
`X-Coder-Workspace-Id`	Workspace associated with the chat, if any.

Coder sends the same identity headers to LLM providers, so a first-party MCP server can correlate a tool call back to the originating chat.

Because the headers leak chat identity, the option is off by default and should only be enabled for first-party or trusted internal MCP servers. If the auth header for the configured auth_type collides with one of these headers, the auth header wins.

Permissions

Action	Required role
Create, update, or delete	Admin (deployment config)
View enabled servers	Any authenticated user
OAuth2 connect and disconnect	Any authenticated user

Non-admin users only see enabled servers. Sensitive fields such as API keys and client secrets are redacted in API responses.