Core documentation

1. Base on JSON-RPC 2.0

Specification metadata

adr: 1
title: Base on JSON-RPC 2.0
status: accepted
date: 2026-06-16

§Context

The existing tools (rox, crg, cix, tsserver) each reinvented NDJSON-over-Unix-socket request/response with slightly different framing. We need one wire for the inner seam, and we want server-pushed events (watch diagnostics, skew) and request multiplexing.

§Decision

Use JSON-RPC 2.0, newline-delimited. It is the same family as LSP/MCP/BSP, gives us request/response + notifications + cancellation + error objects with codes, and is a tiny step from the NDJSON the tools already speak. stdio is the conformance floor; Unix socket is an advertised capability for warm shared servers.

§Consequences

Implementers already know the shape; many robustness tools ship JSON-RPC/LSP servers already.
We get notifications for free (push diagnostics, progress) and request ids for multiplexing.
We are not adopting LSP’s method set or document model — see ADR 0002.