Signal CLI by Foxl AI provides a lightweight, cross-platform command-line interface for the Signal messenger service. It includes an MCP server, positioning it as a tool for integrating AI agents into communication workflows. Written in Rust, this free utility allows developers and enterprise teams to programmatically interact with the secure messaging platform. Its design supports various operating systems, offering multiple distribution methods to ensure broad accessibility. Signal CLI enables AI agents to automate message handling and platform interactions, expanding the capabilities of Signal for advanced applications.

What does Signal CLI connect to?

Signal CLI connects directly to the Signal messenger service, acting as a command-line interface. It functions as an MCP server, enabling AI agents to integrate with and manage Signal accounts. This connection allows for sending and receiving messages and performing other interactions within the secure Signal platform. Compatible AI clients that can interact with MCP servers like Signal CLI include Claude, ChatGPT, Hermes, and OpenClaw, facilitating advanced communication automations.

Core features and tools

Signal CLI functions as an MCP server for AI integration with the Signal platform. While specific callable tools are not explicitly documented for this project, similar integrations commonly expose functionalities such as send_message_to_user, send_message_to_group, and receive_message. The primary capability is enabling AI agents to interact with Signal messages and the platform itself. Transport protocols generally supported by MCP include standard input/output, Server-Sent Events, and streamable HTTP.

Who is it for?

Signal CLI is intended for developers and enterprise teams seeking to integrate AI agents into their communication workflows. It empowers these users to automate interactions with the Signal platform, such as sending and receiving messages. The tool supports tasks like reading, searching, and acting on messages programmatically. This allows for the creation of sophisticated AI-driven communication solutions. Skip this if your objective does not involve programmatic AI integration with Signal.

How to get started

Access is granted through connecting to a Signal account. This involves either linking as a secondary device by scanning a QR code displayed in the terminal using an existing Signal mobile app, or registering a new phone number directly, which requires obtaining a captcha token and then verifying via SMS or voice call.

Use cases

• Enabling AI agents to send and receive Signal messages.
• Automating AI agent interaction with the Signal platform for tasks such as reading messages.
• Supporting AI agents in searching and acting on messages within Signal.

Signal CLI by Foxl AI offers a powerful, free solution for integrating AI agents with the Signal messenger service. Built in Rust, it provides a cross-platform MCP server for developers and enterprise teams to automate secure communications. Its authentication methods allow flexible setup for Signal accounts. This tool simplifies programmatic interaction with the Signal platform for AI-driven workflows. Try enabling an AI agent to send messages to a specific user or group.