siyuan-codex-bridge

SiYuan Notes ships with a full official MCP endpoint, yet Codex Desktop, Codex CLI, IDE clients, and DeepSeek Harness have no built-in way to reach it. siyuan-codex-bridge is a local STDIO proxy that forwards MCP requests from any of these clients to 127.0.0.1:6806 and injects the API token automatically—resolving it from environment variables, a local config file, or SiYuan's own workspace settings in that order, so a typical install works out of the box with zero manual token entry.

The design revolves around controlled access. On every tools/call the bridge re-reads the active operation profile (readonly, authoring, or full), so a policy change takes effect on the very next call without restarting anything. The tool catalog falls back through three tiers—live endpoint, local cache, bundled snapshot—ensuring tools never render as empty even before SiYuan has ever been opened. Beyond the official note tools, the bridge exposes SiYuan's built-in AI as an additional MCP action set (chat, agent, editor, action) with interactive approval, streaming aggregation, and session-level permissions. An opt-in launchOnCall switch can start the SiYuan desktop app on demand, stripping environment variables that would break an Electron process, while a local audit.jsonl records only timestamps, levels, tools, and decisions—never note content or tokens.

Built for SiYuan power users who also rely on Codex or DSH for daily note retrieval, writing, and annotation. If you want an agent to read and edit notes within strict bounds, to call SiYuan AI for Q&A or editing tasks, and to keep everything on localhost, this bridge provides a local, dependency-free connection layer with hard policy enforcement on every single call.