Signal: a private, end-to-end encrypted channel to your agent

What Signal is for

Signal encrypts transport, but Hermes requires an external signal-cli linked-device daemon. Decrypted messages reach the Hermes host, configured model and tools; the messenger alone does not make all processing private or local. Choose explicit user grants. Group chats stay ignored until you list specific group IDs. A home channel can receive scheduled results.

What you need

• signal-cli (from GitHub releases on Linux, or Homebrew on macOS) and Java 17 or later
• A phone number with Signal installed to link signal-cli as a secondary device
• A way to keep the signal-cli daemon running, such as systemd, tmux or screen

Set it up

1. 1

   Install signal-cli, for example brew install signal-cli on macOS

2. 2

   Run signal-cli link -n "HermesAgent" and scan the QR code from Signal's Linked Devices screen on your phone

3. 3

   Start the daemon with signal-cli --account +1234567890 daemon --http 127.0.0.1:8080, using your own E.164 number

4. 4

   Run hermes gateway setup and choose Signal, or set SIGNAL_HTTP_URL, SIGNAL_ACCOUNT and SIGNAL_ALLOWED_USERS in ~/.hermes/.env

5. 5

   Start the gateway with hermes gateway or hermes gateway install

Check it works

• Run curl http://127.0.0.1:8080/api/v1/check and confirm it returns JSON with the signal-cli version
• The setup wizard tests connectivity to the daemon
• Message the bot from an allowed number. If pairing is enabled and a code is issued, approve it with hermes pairing approve signal CODE. A restrictive allowlist normally suppresses unsolicited codes.

Limits and failure points

• Signal cannot edit sent messages, so tool-progress updates are suppressed; replies over 8,000 characters are split into chunks
• Running more than one signal-cli listener on the same number produces duplicate messages
• Voice input uses the configured speech-to-text provider when available, including documented local, hosted or custom providers. Spoken replies can be attached as audio. The signal-cli data folder contains account credentials.

Messaging setup

All messaging platforms

• How to set up Hermes Agent on Signal

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