MCP Gateway integration

1. Register your MCP server

target_url is your MCP server's JSON-RPC endpoint. audience is the aud value your delegation tokens should carry for this gateway. upstream_auth is optional — the bearer token AGF sends to your MCP server, if it requires one. Requires a Growth plan or above.

curl -X POST https://api.agentgovernancefoundation.com/v1/mcp-gateways \
  -H "X-AGF-Key: agfk_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "prod-tools-server",
    "target_url": "https://mcp.internal.acme.com/mcp",
    "audience": "mcp-prod",
    "upstream_auth": "your-mcp-servers-own-bearer-token"
  }'

Response includes the gateway ID you'll route traffic to. The secret is never echoed back.

{
  "id": "a1b2c3d4-...",
  "name": "prod-tools-server",
  "target_url": "https://mcp.internal.acme.com/mcp",
  "audience": "mcp-prod",
  "enabled": true,
  "log_tool_arguments": false,
  "timeout_ms": 30000
}

2. Point your MCP traffic at the gateway

Call /mcp/{gateway_id} instead of your MCP server directly. tools/call and resources/read — the two methods most likely to have side effects or expose data — need a delegation chain in the X-AGF-Chain header (a JSON array of the same JWTs /v1/decide accepts). Read-only discovery methods like tools/list pass straight through once your API key checks out — no chain needed.

curl -X POST https://api.agentgovernancefoundation.com/mcp/a1b2c3d4-... \
  -H "X-AGF-Key: agfk_your_key_here" \
  -H "X-AGF-Chain: [\"eyJhbGciOi...\"]" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": { "name": "send_invoice", "arguments": { "customer_id": "cus_123" } }
  }'

What a blocked call looks like

A non-ALLOW decision never reaches your MCP server. The caller gets a standard JSON-RPC error instead of an AGF-specific shape — any MCP client already knows how to handle this without new code:

{
  "jsonrpc": "2.0",
  "id": 1,
  "error": {
    "code": -32000,
    "message": "AGF decision: DENY",
    "data": { "artifact_id": "dec_...", "approval_request_id": null }
  }
}

Which methods get a decision

Delegation chains travel over this stopgap header today rather than a protocol-native field, since MCP has no standard place to carry one yet — see the MCP Gateway blog post for where this is headed.