Lajdar

Signal Claude Bridge — Development skill for Claude Code

Development community

Daemon connects end-to-end encrypted Signal message to a Claude Code agent.

How to install Signal Claude Bridge

This entry records only its repository, not the path inside it, so there is no exact command to give. Open Lajdar/signal-claude-bridge and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

What Signal Claude Bridge does

Daemon connects end-to-end encrypted Signal message to a Claude Code agent. Whitelisting, prompt injection mitigation, permission isolation, and subprocess invocation with no shell involvement.

Alternatives in Development

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Bypass 403 — Probe a 403/401 endpoint with the most-paid bypass tricks (header injection, path encoding, method swap, WAF f 4.5k ★
Claude Supermemory — Persistent memory across sessions and projects using Supermemory 2.3k ★

README

Signal-Claude Bridge

A lightweight daemon that connects Signal Messenger to Claude Code AI agents via signal-cli's JSON-RPC interface. Send a message on Signal, get an AI-powered response — no app, no web UI, just your existing Signal conversations.

Use it to build a personal assistant, a network diagnostics bot, a home automation helper, or anything else a Claude Code agent can do.

Architecture

Signal App                signal-cli daemon            this bridge              Claude Code CLI
    │                          │                           │                         │
    │──── encrypted msg ──────>│                           │                         │
    │                          │── JSON-RPC notification ─>│                         │
    │                          │                           │── claude -p --agent ───>│
    │                          │                           │                         │
    │                          │                           │<── stdout response ─────│
    │                          │<── JSON-RPC send ─────────│                         │
    │<─── encrypted msg ───────│                           │                         │

Features

Zero dependencies — stdlib-only Python, no pip install needed
Single file — the entire bridge is one ~450-line Python script
Agent-agnostic — works with any Claude Code agent, or none (uses default Claude behavior)
Whitelist access control — only configured phone numbers get responses
Input sanitization — control characters stripped, XML tag breakout prevented, message length enforced
Prompt injection mitigation — user input wrapped in untrusted delimiters with scope enforcement
Config validation — agent names validated, broad permission patterns flagged at startup
Isolated permissions — optional dedicated settings file keeps bridge permissions separate from your interactive Claude config
Rate limiting — per-sender