Carapace
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Communication

Signal

E2E encrypted messaging via Signal

Signal Setup Guide

Enables your agent to send and receive end-to-end encrypted messages via Signal.

Prerequisites

  • A Signal account with a registered phone number
  • signal-cli installed on your computer (used for the initial linking process)

Step 1: Install signal-cli

signal-cli is a command-line tool for interacting with Signal. You'll use it to link a device and export the account data for Carapace.

macOS (Homebrew):

brew install signal-cli

Linux: Download the latest release from github.com/AsamK/signal-cli/releases and follow the installation instructions.

Link signal-cli as a secondary device on your Signal account:

signal-cli link -n "Carapace Agent"

This will output a tsdevice: URI. Convert it to a QR code (or use qrencode) and scan it with Signal on your phone:

  1. Open Signal on your phone
  2. Go to Settings > Linked Devices
  3. Tap Link New Device
  4. Scan the QR code

Step 3: Export Account Data

After linking, export the account data that Carapace needs:

signal-cli -a +1234567890 jsonRpc

The account data is stored in ~/.local/share/signal-cli/data/ (Linux) or ~/Library/Application Support/signal-cli/data/ (macOS).

Step 4: Connect in Carapace

  1. Go to Dashboard > Connections
  2. Find Signal and click Connect
  3. Enter your phone number (with country code, e.g., +1234567890)
  4. Paste the account data
  5. Click Save Credentials

Credential Fields Reference

FieldRequiredFormatDescription
phone_numberYesE.164 format (+1234567890)Phone number registered with Signal
account_dataYesJSONLinked device account data from signal-cli

Gotchas

Phone number format: Always include the country code with a + prefix (E.164 format). For example, a US number should be +12025551234, not 2025551234.

Secondary device only: signal-cli must be linked as a secondary device — it cannot take over your primary Signal registration. Your phone remains the primary device.

signal-cli version: Ensure you're using a recent version of signal-cli. Older versions may have compatibility issues with the current Signal protocol.

Re-linking: If the linked device is removed from your Signal account (via Settings > Linked Devices), you'll need to repeat the linking process and update the credentials in Carapace.

See Also