Module envelope 

The minimal JSON-RPC 2.0 envelope the control catalog rides in.

Transport-agnostic: a JsonRpcRequest carries a control method + its typed params, and a JsonRpcResponse carries either a result or an error (ControlError). The catalog does not own the transport (dig-ipc session, loopback-mTLS HTTP/WebSocket) — only these payload shapes that travel over it. The shapes are byte-identical to what dig-node emits so both sides serialize the same bytes.

Structs

JsonRpcRequest

A JSON-RPC 2.0 request: {jsonrpc:"2.0", id, method, params}.

JsonRpcResponse

A JSON-RPC 2.0 response: exactly one of result or error is present.

Enums

RequestId

A JSON-RPC 2.0 request id: a number, a string, or null. dig-node accepts all three and echoes the id verbatim on the response.