Config File Reference

You can configure Apollo MCP Server using a configuration file. You can also override configuration options using environment variables.

See the example config file for an example.

Configuration options

All fields are optional.

Top-level options

GraphOS

These fields are under the top-level graphos key and define your GraphOS graph credentials and endpoints.

Health checks

These fields are under the top-level health_check key. Learn more about health checks.

Introspection

These fields are under the top-level introspection key. Learn more about the MCP introspection tools.

Logging

These fields are under the top-level logging key.

Operation source

These fields are under the top-level operations key. The available fields depend on the value of the nested source key. The default value for source is "infer". Learn more about defining tools as operations.

Overrides

These fields are under the top-level overrides key.

Schema source

These fields are under the top-level schema key. The available fields depend on the value of the nested source key. The default value for source is "uplink".

Transport

These fields are under the top-level transport key, to configure running the MCP Server in different environments - stdio, Streamable HTTP or SSE (deprecated).

1transport:
2  type: stdio

The available fields depend on the value of the nested type key:

stdio (default)

Streamable HTTP

SSE (Deprecated, use StreamableHTTP)

Auth

These fields are under the top-level transport key, nested under the auth key. Learn more about authorization and authentication.

Below is an example configuration using StreamableHTTP transport with authentication:

1transport:
2  type: streamable_http
3  auth:
4    # List of upstream delegated OAuth servers
5    # Note: These need to support the OIDC metadata discovery endpoint
6    servers:
7      - https://auth.example.com
8
9    # List of accepted audiences from upstream signed JWTs
10    # See: https://www.ory.sh/docs/hydra/guides/audiences
11    audiences:
12      - mcp.example.audience
13
14    # The externally available URL pointing to this MCP server. Can be `localhost`
15    # when testing locally.
16    # Note: Subpaths must be preserved here as well. So append `/mcp` if using
17    # Streamable HTTP or `/sse` is using SSE.
18    resource: https://hosted.mcp.server/mcp
19
20    # Optional link to more documentation relating to this MCP server.
21    resource_documentation: https://info.mcp.server
22
23    # List of queryable OAuth scopes from the upstream OAuth servers
24    scopes:
25      - read
26      - mcp
27      - profile

Example config file

The following example file sets your endpoint to localhost:4001, configures transport over Streamable HTTP, enables introspection, and provides two local MCP operations for the server to expose.

1endpoint: http://localhost:4001/
2transport:
3  type: streamable_http
4introspection:
5  introspect:
6    enabled: true
7operations:
8  source: local
9  paths:
10    - relative/path/to/your/operations/userDetails.graphql
11    - relative/path/to/your/operations/listing.graphql

Override configuration options using environment variables

You can override configuration options using environment variables. The environment variable name is the same as the option name, but with APOLLO_MCP_ prefixed. You can use __ to mark nested options.

For example, to override the introspection.execute.enabled option, you can set the APOLLO_MCP_INTROSPECTION__EXECUTE__ENABLED environment variable.

1APOLLO_MCP_INTROSPECTION__EXECUTE__ENABLED="true"

For list values, you can set the environment variable to a comma-separated list.

For example, to override the transport.auth.servers option, you can set the APOLLO_MCP_TRANSPORT__AUTH__SERVERS environment variable to a comma-separated list.

1APOLLO_MCP_TRANSPORT__AUTH__SERVERS='[server_url_1,server_url_2]'