bg-tasks-mcp

Let your AI agent manage background processes. One sentence to start, monitor, and stop dev servers, builds, and tests — without leaving the conversation.

Why

Working on a full-stack project means juggling multiple terminal windows to start dev servers, check logs, and kill processes. Every context switch breaks your flow. You're the process manager, not the AI.

bg-tasks flips this: the LLM manages background processes for you.

Before:
┌──────────┐   ┌──────────────┐   ┌──────────────┐
│ opencode │   │ Terminal #1  │   │ Terminal #2  │
│ write code│   │ npm run dev  │   │ go run .      │
│ ask Q     │   │ check logs   │   │ check logs    │
└──────────┘   └──────────────┘   └──────────────┘
   ↑ Alt+Tab, manual PID hunting, context switching

After:
┌──────────────────────────────────────────────────┐
│ opencode                                         │
│                                                  │
│ "Start frontend and backend with bg-tasks"       │
│ → bg_start("frontend", "npm run dev")            │
│ → bg_start("backend", "go run .")               │
│                                                  │
│ "Show me frontend logs"                          │
│ → bg_logs(id="frontend", tail=20)                │
│                                                  │
│ "Stop the backend"                                │
│ → bg_kill(id="backend")                          │
│                                                  │
│ Dashboard: http://127.0.0.1:9876                 │
└──────────────────────────────────────────────────┘

Use Cases

Scenario	Example
Dev servers	bg_start("fe", "npm run dev") + bg_start("be", "python app.py")
Builds	bg_start("build", "npm run build") → bg_wait("build") → bg_logs("build")
Tests	bg_start("test", "npm test") → bg_wait("test")
Long scripts	bg_start("seed", "node seed-db.js") — check progress with bg_logs
Multi-project	Open two opencode windows → dashboard shows both projects' tasks

Installation

npm (recommended)

{"command": ["npx", "-y", "bg-tasks-mcp"]}

No install needed — npx downloads and runs on first use.

Manual install

npm install -g bg-tasks-mcp

Then configure:

{"command": ["bg-tasks-mcp"]}

Git clone

git clone https://github.com/rookie136/bg-tasks-mcp.git
cd bg-tasks-mcp
npm install

Then:

{"command": ["node", "/path/to/bg-tasks-mcp/index.js"]}

When you need to start, monitor, or stop background processes (dev servers, builds, tests),
use the bg-tasks tools.

Usage

6 MCP Tools

Tool	Purpose	Example
bg_start	Start a background task	bg_start(name="frontend", command="npm run dev")
bg_wait	Wait for completion or timeout	bg_wait(id="frontend", timeout=30)
bg_logs	Read task output	bg_logs(id="frontend", tail=20, stream="stdout")
bg_status	Inspect or list tasks	bg_status(id="frontend") / bg_status()
bg_send	Send text or signal	bg_send(id="frontend", input="<Enter>")
bg_kill	Terminate a task	bg_kill(id="frontend") / bg_kill(id="frontend", force=true)

5 MCP Resources

Resource	Description
bg://status	All tasks as JSON
bg://{id}/status	Single task detail + log summary
bg://{id}/logs	Combined stdout/stderr
bg://{id}/logs/stdout	stdout only
bg://{id}/logs/stderr	stderr only

Web Dashboard

When the first opencode window starts, the HTTP dashboard comes online automatically:

http://127.0.0.1:9876          English (default)
http://127.0.0.1:9876/?lang=zh 中文

Features:

• Window list (owner PID, remote PIDs, task counts, last active time)
• Real-time running tasks view
• Clickable log links for remote window tasks
• Per-window history with clear buttons
• Bilingual UI (EN/中文 toggle)

Architecture

Multi-Window Design

┌─ opencode window #1 (owner) ──────────────────────────────────────┐
│  bg-tasks process                                                  │
│                                                                     │
│  serveStdio (MCP stdio)  ←─ LLM tool calls                         │
│  HTTP :9876                                                         │
│    GET /              → dashboard HTML (bilingual)                 │
│    GET /status        → JSON API                                   │
│    GET /logs/{id}     → log page                                   │
│    POST /api/report   → receive remote window tasks               │
│    GET /api/health    → liveness probe                             │
│                                                                     │
│  orphan check (30s) → parent alive? → 3 fails → self-terminate    │
└─────────────────────────────────────────────────────────────────────┘

┌─ opencode window #2 (non-owner) ───────────────────────────────────┐
│  bg-tasks process                                                  │
│                                                                     │
│  serveStdio (MCP stdio)  ←─ own LLM tool calls                    │
│  mini HTTP :9877                                                    │
│    GET /logs/{id} → log page (read-only)                          │
│                                                                     │
│  reporter → every 10s POST /api/report (:9876) push task state    │
│  health check → every 5s GET /api/health (:9876) → owner alive?   │
│    → takeover :9876 → become new owner → close mini HTTP           │
└─────────────────────────────────────────────────────────────────────┘

Owner/Takeover Lifecycle

Window #1 starts → binds :9876 → owner → dashboard online
Window #2 starts → EADDRINUSE → non-owner → mini HTTP :9877 → reporter push
Window #3 starts → EADDRINUSE → non-owner → mini HTTP :9878 → reporter push

Window #1 closes → health check fails → Window #2 jitter 500-1500ms → binds :9876
  → new owner → closes mini HTTP :9877 → tasks become local

Window #2 closes → Window #3 takes over
All windows closed → orphan check triggers → self-terminate

Data Flow

non-owner window                  owner window
─────────────────                 ─────────────
bg_start("server", ...)  ──┐
bg_start("client", ...)  ──┤
                              │
reporter (10s interval)  ◄────┘
  │
  │ POST /api/report { pid, port, tasks: [...] }
  ▼
owner dashboard ──► aggregates remote + local tasks
  │
  ├─ GET / → dashboard HTML (window list, running, history)
  ├─ GET /logs/{id} → local task logs (from MemoryLogStore)
  └─ remote task links → http://127.0.0.1:{port}/logs/{id} (mini HTTP)

Logging System

JSONL format written to <install-dir>/.log:

{"ts":"20260809T023839","evt":"owner_ok","pid":30508,"port":9876,"ppid":11972}
{"ts":"20260809T023900","evt":"bg_start","pid":30508,"id":"d26c6305","name":"backend","cmd":"python..."}
{"ts":"20260809T024200","evt":"bg_exit","pid":30508,"id":"d26c6305","exit":0,"ms":60000}
{"ts":"20260809T024503","evt":"orphan_check","pid":30508,"attempt":1,"alive":false}
{"ts":"20260809T030000","evt":"shutdown","pid":30508,"reason":"SIGTERM"}

Auto-rotation: 1MB per file, keeps last 2 backups (.log.0, .log.1).

i18n

Translations are JSON files in lib/i18n/. To add a new language, copy en.json to <lang>.json and translate the values.

lib/i18n/
├── en.json     # English (default, fallback)
└── zh.json     # 中文

File Structure

bg-tasks-mcp/
├── index.js              # entry: MCP stdio + owner detection + orphan check
├── lib/
│   ├── store.js           MemoryLogStore (ring buffer, 4MB per key)
│   ├── registry.js        TaskRegistry (state machine, onTaskEvent hook)
│   ├── platform.js        Windows/Unix adaptation (shell, kill, signal)
│   ├── session.js         session ID generation
│   ├── status-http.js     HTTP dashboard + routes + multi-window aggregation
│   ├── reporter.js        non-owner task state push (10s interval)
│   ├── logger.js          JSONL file logger (1MB rotation)
│   ├── i18n.js            i18n loader (in-memory cache, en fallback)
│   └── i18n/
│       ├── en.json         English translations
│       └── zh.json         中文翻译
├── tools/                 6 MCP tools (bg_start, bg_wait, bg_logs, etc.)
├── resources/             MCP resources (bg://status, bg://{id}/logs, etc.)
└── test/                  Node.js native test runner

Environment Variables

Variable	Description	Default
BG_TASKS_NO_ORPHAN_CHECK	Set to 1 to disable orphan detection	off

Platform

Node.js 18+, Windows/Linux/macOS. Windows uses taskkill instead of POSIX signals.

License

MIT