Add Signal

Add Signal Channel

Adds Signal messaging support via a native adapter that speaks JSON-RPC to a signal-cli TCP daemon. No Chat SDK bridge — only Node.js builtins (node:net, node:child_process, node:fs).

Unlike Telegram or Discord, Signal has no bot API. NanoClaw registers as a full Signal account on a dedicated phone number (recommended) or links as a secondary device on your existing number.

Prerequisites

Java

signal-cli requires Java 17+:

java -version

If missing:

• macOS: brew install --cask temurin@17
• Debian/Ubuntu: sudo apt-get install -y default-jre
• RHEL/Fedora: sudo dnf install -y java-17-openjdk

Java 17–25 all work.

signal-cli

• macOS: brew install signal-cli
• Linux: download the native binary from GitHub releases:

SIGNAL_CLI_VERSION=$(curl -fsSL https://api.github.com/repos/AsamK/signal-cli/releases/latest | python3 -c "import sys,json; print(json.load(sys.stdin)['tag_name'][1:])")
curl -fsSL "https://github.com/AsamK/signal-cli/releases/download/v${SIGNAL_CLI_VERSION}/signal-cli-${SIGNAL_CLI_VERSION}-Linux-native.tar.gz" \
  | tar -xz -C ~/.local
ln -sf ~/.local/signal-cli ~/.local/bin/signal-cli
signal-cli --version

The Linux native tarball extracts a single binary directly to ~/.local/signal-cli (not into a subdirectory). The symlink above puts it on PATH.

Registration

Two paths. The new-number path is recommended and battle-tested.

Path A: Register a new number (recommended)

Use a dedicated SIM or VoIP number. NanoClaw owns it entirely.

VoIP numbers: Signal requires SMS verification before voice. Some VoIP providers are blocked even for voice calls. If registration fails with an auth error, try a different provider or a physical SIM.

Step 1: Solve the CAPTCHA

Signal requires a CAPTCHA on first registration:

1. Open https://signalcaptchas.org/registration/generate.html in a browser
2. Solve the captcha
3. Right-click the "Open Signal" button → Copy Link
4. The link starts with signalcaptcha:// — the token is everything after that prefix

Step 2: Request SMS verification

signal-cli -a +1YOURNUMBER register --captcha "PASTE_TOKEN_HERE"

Step 3: Voice call fallback (if your number can't receive SMS)

Wait ~60 seconds after the SMS request, then:

signal-cli -a +1YOURNUMBER register --voice --captcha "SAME_TOKEN"

Signal calls your number and reads a 6-digit code. The same captcha token is reusable — no need to solve a new one.

You must request SMS first. Requesting voice immediately fails with Invalid verification method: Before requesting voice verification…

Step 4: Verify

signal-cli -a +1YOURNUMBER verify CODE

No output = success.

Step 5: Set profile name (optional)

⚠ Stop NanoClaw before running signal-cli commands — the daemon holds an exclusive lock on its data directory while running.

# macOS
launchctl unload ~/Library/LaunchAgents/com.nanoclaw.plist
signal-cli -a +1YOURNUMBER updateProfile --name "YourBotName"
# optionally: --avatar /path/to/avatar.jpg
launchctl load ~/Library/LaunchAgents/com.nanoclaw.plist

# Linux
systemctl --user stop nanoclaw
signal-cli -a +1YOURNUMBER updateProfile --name "YourBotName"
systemctl --user start nanoclaw

Path B: Link as secondary device

Joins an existing Signal account as a secondary device. Simpler, but NanoClaw shares your personal number.

signal-cli -a +1YOURNUMBER link --name "NanoClaw"

This prints a tsdevice: URI. Scan it as a QR code on your phone: Settings → Linked Devices → Link New Device. QR codes expire in ~30 seconds — re-run if it expires.

Install

Pre-flight (idempotent)

Skip to Credentials if all of these are already in place:

• src/channels/signal.ts and src/channels/signal.test.ts both exist
• src/channels/index.ts contains import './signal.js';

Otherwise continue. Every step below is safe to re-run.

1. Fetch the channels branch

git fetch origin channels

2. Copy the adapter and tests

git show origin/channels:src/channels/signal.ts      > src/channels/signal.ts
git show origin/channels:src/channels/signal.test.ts > src/channels/signal.test.ts

3. Append the self-registration import

Append to src/channels/index.ts (skip if the line is already present):

import './signal.js';

4. Build

pnpm run build

No npm packages to install — the adapter uses only Node.js builtins.

Credentials

Add to .env:

SIGNAL_ACCOUNT=+1YOURNUMBER

Optional settings

# TCP daemon host and port (default: 127.0.0.1:7583)
SIGNAL_TCP_HOST=127.0.0.1
SIGNAL_TCP_PORT=7583

# Path to the signal-cli binary (default: resolved on PATH)
SIGNAL_CLI_PATH=/usr/local/bin/signal-cli

# Whether NanoClaw manages the daemon lifecycle (default: true).
# Set to false if you run signal-cli daemon externally.
SIGNAL_MANAGE_DAEMON=true

# signal-cli data directory (default: ~/.local/share/signal-cli)
SIGNAL_DATA_DIR=~/.local/share/signal-cli

Security note: keep the TCP host on 127.0.0.1. The daemon has no auth — binding it to a public interface would expose your full Signal account to the network.

Sync to container: mkdir -p data/env && cp .env data/env/env

Restart

# macOS
launchctl kickstart -k gui/$(id -u)/com.nanoclaw

# Linux
systemctl --user restart nanoclaw

Wiring

DMs

After the service starts, send any message to the Signal number from your personal Signal app. The router auto-creates a messaging_groups row. Then:

sqlite3 data/v2.db \
  "SELECT id, platform_id FROM messaging_groups WHERE channel_type='signal' ORDER BY created_at DESC LIMIT 5"

Pass the id to /init-first-agent or /manage-channels to wire it to an agent group.

Groups

Add the Signal number to a group from your phone, send any message, then wire the resulting row the same way. For isolated per-group sessions:

NOW=$(date -u +"%Y-%m-%dT%H:%M:%S.000Z")
sqlite3 data/v2.db "
INSERT OR IGNORE INTO messaging_group_agents
  (id, messaging_group_id, agent_group_id, session_mode, priority, created_at)
VALUES
  ('mga-'||hex(randomblob(8)), 'mg-GROUPID', 'ag-AGENTID', 'isolated', 0, '$NOW');
"

Grant user access

New Signal users (including the owner's Signal identity) are silently dropped with not_member until granted access. After the user's first message appears in messaging_groups:

NOW=$(date -u +"%Y-%m-%dT%H:%M:%S.000Z")
sqlite3 data/v2.db "
INSERT OR REPLACE INTO user_roles (user_id, role, agent_group_id, granted_by, granted_at)
  VALUES ('signal:UUID', 'owner', NULL, 'system', '$NOW');
INSERT OR IGNORE INTO agent_group_members (user_id, agent_group_id, added_by, added_at)
  VALUES ('signal:UUID', 'ag-AGENTID', 'system', '$NOW');
"

Find the UUID from messaging_groups.platform_id or the users table.

Next Steps

If you're in the middle of /setup, return to the setup flow now.

Otherwise, run /init-first-agent to create an agent and wire it to your Signal DM, or /manage-channels to wire this channel to an existing agent group.

Channel Info

• type: signal
• terminology: Signal has "chats" (1:1 DMs) and "groups"
• supports-threads: no
• platform-id-format:
  • DM: signal:{UUID} — sender's Signal UUID (ACI), not their phone number
  • Group: signal:{base64GroupId} — base64-encoded GroupV2 ID
• how-to-find-id: Send a message to the bot, then query messaging_groups as shown above
• typical-use: Personal assistant via Signal DMs or small group chats
• default-isolation: One agent per Signal account. Multiple chats with the same operator can share an agent group; groups with other people should typically use isolated session mode

Features

• Markdown formatting — **bold**, *italic* / _italic_, `code`, ```code fence```, ~~strike~~, ||spoiler|| (converted to Signal's offset-based text styles)
• Quoted replies — replyTo* fields populated from Signal quotes
• Typing indicators — DMs only (Signal doesn't support group typing)
• Echo suppression — outbound messages matched on (platformId, text) within a 10 s TTL to avoid syncMessage loops
• Note to Self — messages you send to your own account from another device route to the agent as inbound with isFromMe: true
• Voice attachments — detected but not transcribed by default; the agent receives [Voice Message] placeholder text. Run /add-voice-transcription for local transcription via parakeet-mlx

Not supported yet: outbound file attachments (logged and dropped), edit/delete messages, reactions.

Troubleshooting

Daemon not reachable

grep "Signal" logs/nanoclaw.log | tail

If you see Signal daemon failed to start. Is signal-cli installed and your account linked?:

• Confirm signal-cli is on PATH (or set SIGNAL_CLI_PATH)
• Confirm the account is linked: signal-cli -a +1YOURNUMBER listIdentities should succeed without prompting

If you see Signal daemon not reachable at 127.0.0.1:7583 and SIGNAL_MANAGE_DAEMON=false, start the daemon yourself: signal-cli -a +1YOURNUMBER daemon --tcp 127.0.0.1:7583.

Bot not responding

1. Channel initialized: grep "Signal channel connected" logs/nanoclaw.log | tail -1
2. Channel wired: sqlite3 data/v2.db "SELECT mg.platform_id, mg.name FROM messaging_groups mg JOIN messaging_group_agents mga ON mg.id = mga.messaging_group_id WHERE mg.channel_type='signal'"
3. Service running: launchctl print gui/$(id -u)/com.nanoclaw (macOS) / systemctl --user status nanoclaw (Linux)

Lost connection mid-session

If you see Signal channel lost TCP connection to signal-cli daemon in the logs, the daemon dropped the connection. Restart the service to re-establish.

Messages dropped with not_member

The Signal user hasn't been granted membership. See "Grant user access" above. This affects every new Signal user, including the owner's Signal identity — which is a separate user record from their identity on other channels even if it's the same person.

Captcha required

Signal requires a captcha for new registrations. Go to https://signalcaptchas.org/registration/generate.html, solve it, right-click "Open Signal", copy the link, extract the token after signalcaptcha://.

Invalid verification method: Before requesting voice verification…

You must request SMS first, wait ~60 seconds, then request voice. Both steps can use the same captcha token.

Config file in use / daemon lock

signal-cli holds an exclusive lock on its data directory while the daemon is running. Stop NanoClaw before running any signal-cli commands directly, then restart afterward.

Group replies going to DM instead of group

Modern Signal groups use GroupV2. The adapter must extract the group ID from envelope?.dataMessage?.groupV2?.id — not groupInfo?.groupId, which is GroupV1/legacy. If group messages are routing as DMs, check src/channels/signal.ts and confirm the groupId extraction falls through to groupV2.id.

Java not found

Install Java 17+ — see the Prerequisites section above.

QR code expired (Path B)

QR codes expire in ~30 seconds. Re-run the link command to generate a new one.