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Chris edited this page Jul 6, 2026 · 159 revisions

Enterprise HTTP Transport

Tools

Resources

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OAuth 2.1

Code Mode

🚀 Value Proposition

  • Global reach for modern and legacy clients.
  • Scale efficiently to cloud and serverless environments.
  • Enable high-velocity stateless JSON-RPC endpoints.
  • Leverage OAuth 2.1 for enterprise security.
  • Scale operations seamlessly across distributed autonomous agents.

Bridge modern and legacy AI clients with dual-protocol transport to future-proof your infrastructure. This page explains running mysql-mcp as an HTTP server supporting Streamable HTTP and legacy SSE.

Decide When to Use HTTP Mode

Use HTTP mode when:

  • Deploying the server to a remote location (cloud, Docker container)
  • Multiple AI clients need to connect to the same database
  • You need OAuth 2.1 authentication for enterprise security
  • Running the server as a standalone network service
  • Serverless/stateless deployments (--stateless)

Use stdio mode (default) when:

  • Running locally with Claude Desktop or Cursor IDE
  • Single-user development environment
  • Simplest setup with no network configuration needed

💡 Tip: Most users should use stdio mode. HTTP mode is for advanced deployments.

Quick Start

Important:

You must set --allowed-io-roots in HTTP transport mode to authorize filesystem boundaries. The server fails to start without it.

Local Installation

# Local installation
npx -y @neverinfamous/mysql-mcp --transport http --server-host 0.0.0.0 --port 3001 --allowed-io-roots /data --mysql mysql://user:password@localhost:3306/database

Docker

# Run with port mapping
docker run -p 3001:3001 \
  -e MYSQL_HOST=host.docker.internal \
  -e MYSQL_USER=user \
  -e MYSQL_PASSWORD=password \
  -e MYSQL_DATABASE=database \
  writenotenow/mysql-mcp:latest \
  --transport http \
  --server-host 0.0.0.0 \
  --port 3001 \
  --allowed-io-roots /data

With Simple Bearer Auth

npx -y @neverinfamous/mysql-mcp --transport http --server-host 0.0.0.0 --port 3001 --allowed-io-roots /data --auth-token my-secret --mysql mysql://user:password@localhost:3306/database

Stateless Mode

npx -y @neverinfamous/mysql-mcp --transport http --server-host 0.0.0.0 --port 3001 --stateless --allowed-io-roots /data --mysql mysql://user:password@localhost:3306/database

Transport Protocols

The HTTP transport supports two protocol versions, letting modern and legacy clients connect simultaneously.

  • /mcp (Streamable HTTP): The modern protocol using a single endpoint for all communication.
  • /sse (Legacy SSE): The backward-compatible protocol establishing a long-lived Server-Sent Events connection.

Streamable HTTP (Recommended)

Modern protocol (MCP 2025-03-26) — single endpoint, session-based:

Method Endpoint Purpose
POST /mcp JSON-RPC requests (initialize, tools/list, etc.)
GET /mcp SSE stream for server notifications
DELETE /mcp Session termination

In stateless mode (--stateless): GET /mcp returns 405. DELETE /mcp returns 204. /sse and /messages return 404. Each POST /mcp creates a fresh transport relying solely on synchronous request-response cycles.

Warning

Stateless Limitations: --stateless disables resource subscriptions and progress notifications by entirely disabling Server-Sent Events. Do not use this mode if your AI relies on long-running task updates.

The Mcp-Session-Id header manages sessions. The server returns a session ID during initialize. Clients must include it in subsequent requests.

Example — Initialize a session:

curl -X POST http://localhost:3001/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"my-client","version":"1.0.0"}}}'

Example — List tools (with session):

curl -X POST http://localhost:3001/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "Mcp-Session-Id: <session-id-from-initialize>" \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}'

Important:

Streamable HTTP requests must include Accept: application/json, text/event-stream.

Legacy SSE (Backward Compatibility)

Legacy protocol (MCP 2024-11-05) — for older MCP clients:

Method Endpoint Purpose
GET /sse Opens SSE stream, returns /messages?sessionId=<id> endpoint
POST /messages?sessionId=<id> Send JSON-RPC messages to the session

Example:

# Establish SSE connection (will stream events)
curl -N http://localhost:3001/sse
# Send a message (in another terminal, using the sessionId from the SSE stream)
curl -X POST "http://localhost:3001/messages?sessionId=<id>" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"my-client","version":"1.0.0"}}}'

Security Headers

All HTTP responses include the following headers (6 base, 7 with HSTS):

Header Value
X-Content-Type-Options nosniff
X-Frame-Options DENY
Cache-Control no-store, no-cache, must-revalidate
Content-Security-Policy default-src 'none'; frame-ancestors 'none'
Permissions-Policy camera=(), microphone=(), geolocation=()
Referrer-Policy no-referrer
Strict-Transport-Security Opt-in via the --enable-hsts CLI flag or MCP_ENABLE_HSTS environment variable

Server Timeouts (Slowloris Protection)

Warning

Load Balancer Trap: Set your proxy's idle timeout lower than the server's 65,000 ms keepAliveTimeout. Otherwise, the proxy might close active connections and cause 502 Bad Gateway errors.

The HTTP server applies three timeout layers to prevent slow-connection DoS attacks:

Timeout Value Purpose
requestTimeout 120,000 ms Maximum time for the entire request lifecycle
keepAliveTimeout 65,000 ms Idle time before closing keep-alive connections
headersTimeout 66,000 ms Maximum time to receive complete headers

Session Timeouts

The HTTP transport enforces strict session lifecycle management to prevent memory leaks:

  • Idle TTL: 30 minutes. The server terminates idle sessions.
  • Absolute TTL: 24 hours. Hard limit for any session duration.
  • Reaper Interval: 1 minute. A background sweep cleans up orphaned sessions. In-flight requests protect sessions from early termination.

CORS

We hardcode CORS to allow all origins (*) for easy web-based client connections. We do not yet support restricting origins via CLI flags.

Trust Proxy

Enable trustProxy behind reverse proxies to read the client IP from X-Forwarded-For. This ensures rate limiting and logging use the real client IP.

Rate Limiting

Default per-IP request throttling prevents abuse. The Transport Rate limiter uses a sliding window approach with deterministic cleanup. Redis distributes rate limiting across deployments if you provide REDIS_URL, with an in-memory fallback. (Note: This differs from the Code Mode rate limit).

  • /health bypass — The server handles health checks before rate limiting, ensuring monitoring probes always succeed.
  • Retry-After header — Rate-limited responses include a Retry-After header showing seconds until the window resets.
  • Environment override — Set MCP_RATE_LIMIT_MAX to customize the per-IP request limit.

Body Size Enforcement

Two layers enforce request body size:

  1. Content-Length header check — fast rejection for well-behaved clients
  2. Streaming byte tracking — catches missing headers and chunked encoding

Default maximum body size: 1 MB (1,048,576 bytes).

Configuration Options

Environment Variables

For production deployments, use a structured .env file following fleet groupings:

# Server
MCP_TRANSPORT=http
MYSQLMCP_PORT=3001
MCP_HOST=0.0.0.0
TRUST_PROXY=false
MCP_RATE_LIMIT_MAX=100
# Database
MYSQL_HOST=localhost
MYSQL_PORT=3306
MYSQL_USER=app_user
MYSQL_PASSWORD=secure_password
MYSQL_DATABASE=production

CLI Arguments

Argument Environment Variable Default Description
--transport, -t MCP_TRANSPORT stdio Transport type (stdio, http, or sse)
--port MYSQLMCP_PORT 3001 HTTP server port
--server-host MCP_HOST localhost Host to bind HTTP transport to
--auth-token MCP_AUTH_TOKEN — Simple bearer token for HTTP auth
--stateless — false Stateless HTTP mode (no sessions, no SSE)
--trust-proxy TRUST_PROXY false Trust X-Forwarded-For for client IP
--enable-hsts MCP_ENABLE_HSTS false Enable HTTP Strict Transport Security
--metrics-export MCP_METRICS_EXPORT false Enable prometheus metrics endpoint /metrics
--allowed-io-roots ALLOWED_IO_ROOTS — Explicitly authorize filesystem boundaries
--oauth-enabled, -o OAUTH_ENABLED false Enable OAuth 2.1 authentication
--oauth-issuer OAUTH_ISSUER — OAuth 2.1 issuer URL
--oauth-audience OAUTH_AUDIENCE mysql-mcp-client OAuth 2.1 audience
--oauth-jwks-uri OAUTH_JWKS_URI — JWKS URI (auto-discovered)
--oauth-clock-tolerance OAUTH_CLOCK_TOLERANCE 60 Clock tolerance in seconds
--audit-log — — Enable JSONL forensic logging and tokens
--audit-backup — false Enable audit backups
--audit-reads — false Include read-scope tool calls in audit log
--audit-redact — false Redact sensitive arguments in audit log
--audit-log-max-size — — Max file size before rotation (bytes)
--audit-backup-data — false Include sample data in pre-mutation snaps
--audit-backup-max-size — — Max table size in bytes for data capture
--pool-size MYSQL_POOL_SIZE 10 Maximum connection pool size
--pool-timeout MYSQL_POOL_TIMEOUT 30000 Connection pool timeout in ms
--pool-queue-limit MYSQL_POOL_QUEUE_LIMIT 0 Connection pool queue limit
— CODE_MODE_MAX_RESULT_SIZE 102400 Max Code Mode result payload in bytes
— MCP_REQUEST_TIMEOUT 120000 Global request timeout in ms
— MCP_HEADERS_TIMEOUT 66000 Global headers timeout in ms
— MCP_KEEPALIVE_TIMEOUT 65000 Keep-alive timeout in ms

Note: The --stateless configuration lacks an environment variable equivalent.

Secure with OAuth 2.1

HTTP mode supports OAuth 2.1 authentication for enterprise deployments:

npx -y @neverinfamous/mysql-mcp \
  --transport http \
  --port 3001 \
  --allowed-io-roots /data \
  --mysql mysql://user:password@localhost:3306/database \
  --oauth-enabled \
  --oauth-issuer http://localhost:8080/realms/mysql-mcp \
  --oauth-audience mysql-mcp-client

See the OAuth page for complete setup instructions.

Connect Clients

Using MCP Inspector

Test your HTTP server with MCP Inspector:

# Start the server
npx -y @neverinfamous/mysql-mcp --transport http --server-host 0.0.0.0 --port 3001 --allowed-io-roots /data --mysql mysql://...
# In another terminal, connect Inspector
npx -y @modelcontextprotocol/inspector http://localhost:3001/sse

Health Check

curl http://localhost:3001/health
# {"status":"healthy","timestamp":"2026-03-05T..."}

Deploy with Docker

Basic Deployment

# Run container with port mapping
docker run -d \
  --name mysql-mcp-server \
  -p 3001:3001 \
  -e MYSQL_HOST=host.docker.internal \
  -e MYSQL_USER=user \
  -e MYSQL_PASSWORD=password \
  -e MYSQL_DATABASE=database \
  writenotenow/mysql-mcp:latest \
  --transport http \
  --server-host 0.0.0.0 \
  --port 3001 \
  --allowed-io-roots /data

Docker Compose

# Note: Always include a healthcheck when deploying HTTP transport
services:
  mysql-mcp:
    image: writenotenow/mysql-mcp:latest
    ports:
      - "3001:3001"
    command:
      - --transport
      - http
      - --server-host
      - "0.0.0.0"
      - --port
      - "3001"
      - --allowed-io-roots
      - /data
      - --mysql
      - mysql://user:password@mysql:3306/database
    environment:
      - MYSQL_POOL_SIZE=20
    depends_on:
      - mysql
  mysql:
    image: mysql:8
    environment:
      MYSQL_ROOT_PASSWORD: password
      MYSQL_DATABASE: database
    volumes:
      - mysql-data:/var/lib/mysql
volumes:
  mysql-data:

Scale in Cloud

AWS ECS / Fargate

  1. Push Docker image to ECR
  2. Create ECS task definition with port 3001 exposed
  3. Configure ALB to route traffic to the container
  4. Set environment variables for MySQL connection

Google Cloud Run

# Build and push to GCR
gcloud builds submit --tag gcr.io/PROJECT_ID/mysql-mcp

# Deploy to Cloud Run
gcloud run deploy mysql-mcp \
  --image gcr.io/PROJECT_ID/mysql-mcp \
  --port 3001 \
  --set-env-vars MYSQL_HOST=...,MYSQL_USER=...,MYSQL_PASSWORD=... \
  --command "--transport,http,--port,3001,--allowed-io-roots,/data"

Azure Container Instances

az container create \
  --resource-group myResourceGroup \
  --name mysql-mcp \
  --image writenotenow/mysql-mcp:latest \
  --ports 3001 \
  --environment-variables \
    MYSQL_HOST=... \
    MYSQL_USER=... \
    MYSQL_PASSWORD=... \
  --command-line "--transport http --server-host 0.0.0.0 --port 3001 --allowed-io-roots /data"

Troubleshooting

Connection Refused

Problem: Client cannot connect to the server

Solutions:

  • Verify server is running: curl http://localhost:3001/health
  • Check firewall rules allow port 3001
  • Ensure --server-host 0.0.0.0 if connecting from another machine
  • Check Docker port mapping: -p 3001:3001

406 Not Acceptable (Streamable HTTP)

Problem: POST /mcp returns 406

Solution: Include the required Accept header:

Accept: application/json, text/event-stream

The server requires clients to accept JSON and SSE formats.

Session Not Found

Problem: Requests return 400 Bad Request or 404 Not Found with session errors

Solutions:

  • Send the Mcp-Session-Id header from the initialize response
  • Cross-protocol guard prevents mixing SSE sessions and /mcp
  • Sessions expire when clients disconnect

OAuth Authentication Failures

Problem: Requests return 401 Unauthorized

Solutions:

  • Verify OAuth issuer URL is correct
  • Check token audience matches --oauth-audience
  • Ensure JWKS URI is accessible from the server
  • See OAuth troubleshooting section

See Also

MySQL MCP Documentation

Unlock autonomous database orchestration with an enterprise-grade MySQL MCP server. Featuring blazing-fast sandboxed Code Mode, uncompromising schema enforcement, and seamless ecosystem integrations to power secure, intelligent AI workflows.

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