Send a Model Context Protocol message

POST 
/v1/mcp

Send a JSON-RPC message to the Spice MCP server using the MCP Streamable HTTP transport. The response is either a single JSON-RPC response (application/json) or an SSE stream (text/event-stream), selected via the Accept header. Session continuity is carried via the Mcp-Session-Id header.

Request

Responses

200

JSON-RPC response. Returned as application/json for a single response or text/event-stream when the server streams additional messages.

202

Message accepted (for JSON-RPC notifications / responses that do not require a reply).

400

Malformed JSON-RPC payload.

401

Unauthorized. The /v1/mcp endpoint requires runtime.auth to be configured. Configure an API key provider in your Spicepod and retry with credentials.

403

Forbidden. The Host header value is not in the runtime.mcp.allowed_hosts list. Configure runtime.mcp.allowed_hosts or set it to ["*"] to allow all hosts.

404

Unknown or expired Mcp-Session-Id.

413

Payload too large. Maximum allowed size is 32 MiB.