Apollo MCP Server Guide
Apollo MCP Server exposes GraphQL operations as MCP tools, enabling AI agents to interact with GraphQL APIs through the Model Context Protocol.
Quick Start
Step 1: Install
bash# Linux / MacOS curl -sSL https://mcp.apollo.dev/download/nix/latest | sh # Windows iwr 'https://mcp.apollo.dev/download/win/latest' | iex
Step 2: Configure
Create config.yaml in your project root:
yaml# config.yaml transport: type: streamable_http schema: source: local path: ./schema.graphql operations: source: local paths: - ./operations/ introspection: introspect: enabled: true search: enabled: true validate: enabled: true execute: enabled: true
Start the server:
bashapollo-mcp-server ./config.yaml
The MCP endpoint is available at http://127.0.0.1:8000/mcp (streamable_http defaults: address 127.0.0.1, port 8000). The GraphQL endpoint defaults to http://localhost:4000/ — override with the endpoint key if your API runs elsewhere.
Step 3: Connect
Add to your MCP client configuration:
Streamable HTTP (recommended):
Claude Desktop (claude_desktop_config.json):
json{ "mcpServers": { "graphql-api": { "command": "npx", "args": ["mcp-remote", "http://127.0.0.1:8000/mcp"] } } }
Claude Code:
bashclaude mcp add graphql-api -- npx mcp-remote http://127.0.0.1:8000/mcp
Stdio (client launches the server directly):
Claude Desktop (claude_desktop_config.json) or Claude Code (.mcp.json):
json{ "mcpServers": { "graphql-api": { "command": "./apollo-mcp-server", "args": ["./config.yaml"] } } }
Built-in Tools
Apollo MCP Server provides four introspection tools:
| Tool | Purpose | When to Use |
|---|---|---|
introspect | Explore schema types in detail | Need type definitions, fields, relationships |
search | Find types in schema | Looking for specific types or fields |
validate | Check operation validity | Before executing operations |
execute | Run ad-hoc GraphQL operations | Testing or one-off queries |
Defining Custom Tools
MCP tools are created from GraphQL operations. Three methods:
1. Operation Files (Recommended)
yamloperations: source: local paths: - ./operations/
Each file must contain exactly one operation. Each named operation becomes an MCP tool.
graphql# operations/GetUser.graphql query GetUser($id: ID!) { user(id: $id) { id name email } }
graphql# operations/CreateUser.graphql mutation CreateUser($input: CreateUserInput!) { createUser(input: $input) { id name } }
2. Operation Collections
yamloperations: source: collection id: your-collection-id
Use GraphOS Studio to manage operations collaboratively.
3. Persisted Queries
yamloperations: source: manifest path: ./persisted-query-manifest.json
For production environments with pre-approved operations.
Reference Files
Detailed documentation for specific topics:
- Tools - Introspection tools and minify notation
- Configuration - All configuration options
- Troubleshooting - Common issues and solutions
Key Rules
Security
- Never expose sensitive operations without authentication
- Use
headersconfiguration for API keys and tokens - Disable introspection tools in production (they are disabled by default)
- Set
overrides.mutation_mode: explicitto require confirmation for mutations
Authentication
yaml# Static header headers: Authorization: "Bearer ${env.API_TOKEN}" # Dynamic header forwarding forward_headers: - x-forwarded-token # OAuth (streamable_http transport) transport: type: streamable_http auth: servers: - https://auth.example.com/.well-known/openid-configuration audiences: - https://api.example.com
Token Optimization
Enable minification to reduce token usage:
yamlintrospection: introspect: minify: true search: minify: true
Minified output uses compact notation:
- T = type, I = input, E = enum
- s = String, i = Int, b = Boolean, f = Float, d = ID
- ! = required, [] = list
Mutations
Control mutation behavior via the overrides section:
yamloverrides: mutation_mode: all # Execute mutations directly # mutation_mode: explicit # Require explicit confirmation # mutation_mode: none # Block all mutations (default)
Common Patterns
GraphOS Cloud Schema
yaml# schema.source defaults to uplink — can be omitted when graphos is configured graphos: apollo_key: ${env.APOLLO_KEY} apollo_graph_ref: my-graph@production
Local Development
yamltransport: type: streamable_http schema: source: local path: ./schema.graphql introspection: introspect: enabled: true search: enabled: true validate: enabled: true execute: enabled: true overrides: mutation_mode: all
Production Setup
yamltransport: type: streamable_http endpoint: https://api.production.com/graphql operations: source: manifest path: ./persisted-query-manifest.json graphos: apollo_key: ${env.APOLLO_KEY} apollo_graph_ref: ${env.APOLLO_GRAPH_REF} headers: Authorization: "Bearer ${env.API_TOKEN}" health_check: enabled: true
Docker
yamltransport: type: streamable_http address: 0.0.0.0 port: 8000 endpoint: ${env.GRAPHQL_ENDPOINT} graphos: apollo_key: ${env.APOLLO_KEY} apollo_graph_ref: ${env.APOLLO_GRAPH_REF} health_check: enabled: true
Ground Rules
- ALWAYS configure authentication before exposing to AI agents
- ALWAYS use
mutation_mode: explicitormutation_mode: nonein shared environments - NEVER expose introspection tools with write access to production data
- PREFER operation files over ad-hoc execute for predictable behavior
- PREFER streamable_http transport for remote and multi-client deployments
- USE stdio only when the MCP client launches the server process directly
- USE GraphOS Studio collections for team collaboration

