signal-mcp

This skill should be used when the user asks to "send a Signal message", "reply on Signal", "react to a Signal message", "edit/delete a sent Signal message", "make Signal feel natural", "check who's on Signal", when handling received Signal envelopes (receipts, typing, reactions, decryption errors), or when an MCP tool returns `Unregistered user`, `IDENTITY_FAILURE`, `InvalidPreKeyException`, or other send/receive errors that aren't setup-related. Covers identifier resolution (phone vs username vs UUID), the receive-and-respond loop, human-feeling typing/receipt timing, sending to groups, attachments, and recovering from common errors.

This skill should be used when the user asks to "set up Signal", "install signal-cli", "register Signal account", "link Signal device", "configure SIGNAL_ACCOUNT", or when an MCP tool returns a `signal-cli not found` / `SIGNAL_ACCOUNT not set` / `unregistered account` error. Walks through installing signal-cli, picking between registering a new number and linking as a secondary device, completing verification, and configuring the plugin's environment variables.