Discord Bridge for Autonomous Claude Code Sessions

A developer has built a Discord bridge for autonomous Claude Code sessions to solve the pull-based limitation where Claude only acts when tools fire or CLI input is sent. The system enables real-time two-way chat via WebSocket with local file queueing and push notifications on stop/error events.

Architecture

Inbound flow: Discord → WebSocket → bridge.js → discord-inbox.jsonl → PostToolUse hook → Claude

Outbound flow: Claude → Discord MCP → #claude-code-chat → phone push notification

Components

• bridge.js (~50 lines, discord.js v14): Persistent WebSocket to Discord gateway that listens to a dedicated channel and writes messages as JSONL to a local inbox file with zero API polling.
• PostToolUse hook: Reads local inbox on every tool call with no network calls or throttling — just a file read that takes microseconds versus the 2-minute polling interval used previously.
• PreToolUse hook: Auto-starts the bridge on first tool call of every session, silently doing nothing if already running.
• Outbound webhook: Sends structured STATUS updates on Stop/Error events with per-session named threads auto-created via Discord's thread_name parameter (requires ?wait=true to get channel_id back — default returns 204 empty).

Key Design Decisions

The main architectural shift was using a local file queue over API polling. JSONL with atomic truncation prevents race conditions. The bridge is session-agnostic — Discord history persists across crashes and restarts, allowing multiple agents to share the same channel.

Limitations

Permission approval prompts (1/2/3) still require terminal input since Claude is idle at that point and tools aren't firing. This works for redirecting mid-active-run but not for answering stopped prompts.

Testing Results

Tested on 27K lines analyzed overnight across two parallel sessions, finding 15 bugs and delivering a 6-month roadmap at 5:42 AM. Setup requires three bash files and approximately twenty minutes.