Control Tower Lite

Minimal multi-agent coordination for Claude Code. Full security, zero dependencies.

A lightweight system for coordinating multiple Claude Code sessions on a single machine. 11 tools, HMAC auth, task DAGs, browser dashboard — built with the philosophy that every feature must justify its existence.

Quick Start

# 1. Install MCP server
python install.py

# 2. Start the broker
python launch.py

# 3. Open Claude Code — use the 'join' tool

Architecture

11 Tools

Tool	Purpose	Role
join	Register + discover peers	Everyone
send	Message anyone (* for broadcast)	Everyone
check	Read inbox	Everyone
create_task	Create with dependencies	Architect
list_tasks	Filter by status	Everyone
claim_task	Atomic claim (fails if taken)	Worker
complete_task	Requires artifact summary	Worker
lock_file	Reserve a file path	Everyone
unlock_file	Release a lock	Everyone
set_memory	Shared key-value	Architect
get_memory	Read shared state	Everyone

Design Philosophy

Every tool must justify its existence with a real use case.

Design Decisions

Decision	Rationale
send handles broadcast	recipient='*' replaces a separate broadcast tool. One tool, not two.
send handles blockers	category='blocker' replaces a separate raise_blocker tool. Routing logic belongs in the broker.
No memory versioning	If a decision changes, write a new key. History adds complexity without proportional value.
No worker spawning	Platform-specific shell spawning is fragile across OS. Open a terminal — it takes 2 seconds.
No budget tracking	Token budgets are useful but not essential for the core coordination workflow.
No conversation logging	Audit logging is infrastructure, not a user-facing tool.

What's Non-Negotiable

Feature	Why
HMAC-SHA256 auth	Identity without auth is theater
Role-based access	Architect/worker separation prevents workers from overwriting shared decisions
Identity enforcement	Sender must match token — no spoofing
Content filtering	Injection defense is not optional
Rate limiting	10 msg/min/peer prevents flooding
Dead peer recovery	Task reassignment on crash keeps work moving

The principle: Security is not a feature to be cut. Everything else is negotiable.

Security

• HMAC-SHA256 tokens — generated on registration, validated every request
• Role-based access — architect creates tasks/memory, worker claims/completes
• Identity enforcement — sender_id must match authenticated peer
• Content filtering — blocks tool_use XML, function_call JSON, data: URIs (NFKC normalized)
• Rate limiting — 10 messages per minute per peer
• Localhost only — bound to 127.0.0.1, never exposed

See SECURITY.md for the full security model.

File Structure

control-tower-lite/
  broker.py          # HTTP server + SQLite + auth + security
  mcp_server.py      # 11 MCP tools + heartbeat + identity
  dashboard.html     # Standalone status page
  install.py         # MCP server registration
  launch.py          # Start broker + open dashboard
  tests/
    test_broker.py   # 50 tests — auth, messaging, tasks, DAGs, locks, memory
  SECURITY.md        # Security model documentation
  README.md
  LICENSE            # MIT

License

MIT — see LICENSE.