Signal Channel - IronClaw

The Signal channel enables IronClaw to send and receive messages via Signal Private Messenger using the signal-cli daemon.

Features

Direct messages - Private 1:1 conversations
Group chats - Multi-party conversations (with allowlist)
DM pairing - Approve unknown users before they can message
Typing indicators - Shows when agent is thinking
Attachment support - Send files within ~/.ironclaw/ sandbox
Thread continuity - Conversation history persists across restarts
Privacy mode - Works with users who hide their phone numbers (UUID-based)

Prerequisites

signal-cli daemon with HTTP/JSON-RPC API mode
A registered Signal account for the bot
IronClaw installed and configured

Setup

1. Install signal-cli

macOS (Homebrew):

brew install signal-cli

Linux (Manual):

wget https://github.com/AsamK/signal-cli/releases/download/v0.12.8/signal-cli-0.12.8-Linux.tar.gz
tar xf signal-cli-0.12.8-Linux.tar.gz -C /opt
ln -sf /opt/signal-cli-0.12.8/bin/signal-cli /usr/local/bin/

2. Register Signal Account

Link to existing account (recommended):

# Generate QR code to link
signal-cli link -n "IronClaw Bot"

# Scan QR code with Signal app:
# Settings → Linked Devices → Link New Device

Or register new number:

# Request verification code
signal-cli -a +1234567890 register

# Verify with code from SMS
signal-cli -a +1234567890 verify CODE

3. Start signal-cli Daemon

# Start HTTP/JSON-RPC server
signal-cli --account +1234567890 daemon --http 127.0.0.1:8080

Or use systemd:

# /etc/systemd/system/signal-cli.service
[Unit]
Description=signal-cli daemon
After=network.target

[Service]
Type=simple
ExecStart=/usr/local/bin/signal-cli --account +1234567890 daemon --http 127.0.0.1:8080
Restart=always
User=signal

[Install]
WantedBy=multi-user.target

sudo systemctl enable signal-cli
sudo systemctl start signal-cli

4. Configure IronClaw

Environment variables:

export SIGNAL_HTTP_URL=http://127.0.0.1:8080
export SIGNAL_ACCOUNT=+1234567890
export SIGNAL_ALLOW_FROM=+1234567890  # Your personal number

Or via config file:

ironclaw onboard

Configuration

Set via environment variables or .env file:

# signal-cli daemon URL
SIGNAL_HTTP_URL=http://127.0.0.1:8080

# Bot's Signal account (phone number or UUID)
SIGNAL_ACCOUNT=+1234567890

# Allowed senders for DMs (comma-separated)
SIGNAL_ALLOW_FROM=+1234567890,uuid:abc-123,*

# Allowed groups (comma-separated group IDs)
SIGNAL_ALLOW_FROM_GROUPS=

# DM policy: open | allowlist | pairing
SIGNAL_DM_POLICY=pairing

# Group policy: open | allowlist | disabled
SIGNAL_GROUP_POLICY=allowlist

# Inherit DM allow_from for groups (if group_allow_from is empty)
SIGNAL_GROUP_ALLOW_FROM=

# Ignore attachment-only messages
SIGNAL_IGNORE_ATTACHMENTS=false

# Ignore story messages
SIGNAL_IGNORE_STORIES=true

Configuration Options

Variable	Type	Default	Description
`SIGNAL_HTTP_URL`	`string`	`http://127.0.0.1:8080`	signal-cli daemon HTTP endpoint
`SIGNAL_ACCOUNT`	`string`	required	Bot’s phone number or UUID
`SIGNAL_ALLOW_FROM`	`string`	`""`	Comma-separated phone numbers/UUIDs. `*` allows all. Empty = deny/require pairing
`SIGNAL_ALLOW_FROM_GROUPS`	`string`	`""`	Comma-separated group IDs. `*` allows all groups. Empty = deny all groups
`SIGNAL_DM_POLICY`	`string`	`"pairing"`	`open`, `allowlist`, or `pairing`
`SIGNAL_GROUP_POLICY`	`string`	`"allowlist"`	`open`, `allowlist`, or `disabled`
`SIGNAL_GROUP_ALLOW_FROM`	`string`	`""`	Sender allowlist for group messages. Empty = inherit from `ALLOW_FROM`
`SIGNAL_IGNORE_ATTACHMENTS`	`boolean`	`false`	Drop attachment-only messages
`SIGNAL_IGNORE_STORIES`	`boolean`	`true`	Drop story messages

DM Policies

`open`

Allow all DMs from anyone.

SIGNAL_DM_POLICY=open

`allowlist`

Only accept DMs from pre-approved senders. Silent drop for others.

SIGNAL_DM_POLICY=allowlist
SIGNAL_ALLOW_FROM=+1234567890,uuid:abc-123

`pairing` (default)

Combines allowlist with interactive pairing. Unknown users receive a pairing code:

To pair with this bot, run: `ironclaw pairing approve signal ABC12345`

SIGNAL_DM_POLICY=pairing
SIGNAL_ALLOW_FROM=+1234567890

Group Policies

`disabled`

Ignore all group messages.

SIGNAL_GROUP_POLICY=disabled

`allowlist` (default)

Only process messages from allowed groups AND allowed senders.

SIGNAL_GROUP_POLICY=allowlist
SIGNAL_ALLOW_FROM_GROUPS=group:abc123,group:def456
SIGNAL_GROUP_ALLOW_FROM=+1234567890  # Only this sender in allowed groups

`open`

Process messages from allowed groups (any sender).

SIGNAL_GROUP_POLICY=open
SIGNAL_ALLOW_FROM_GROUPS=group:abc123

Pairing

DM Pairing

When an unknown user sends a DM with dm_policy: "pairing":

User sends a message
Bot replies: To pair with this bot, run: \ironclaw pairing approve signal ABC12345“
You run: ironclaw pairing approve signal ABC12345
User is added to the persistent allow list

Commands

# List pending pairing requests
ironclaw pairing list signal

# Approve a user by code
ironclaw pairing approve signal ABC12345

# List approved users
ironclaw pairing list signal --approved

Privacy Mode (UUID-based)

Signal users can hide their phone numbers. For these users:

sourceNumber is empty
source contains a UUID (e.g., abc-123-def-456)
Use uuid:abc-123-def-456 in allowlists

Example:

SIGNAL_ALLOW_FROM=+1234567890,uuid:abc-123-def-456

The channel automatically normalizes uuid: prefixes when matching.

Attachments

The channel supports sending attachments from the ~/.ironclaw/ sandbox:

OutgoingResponse {
    content: "Here's the report".to_string(),
    attachments: vec!["/home/user/.ironclaw/files/report.pdf".to_string()],
    ..Default::default()
}

Paths outside ~/.ironclaw/ are rejected to prevent path traversal attacks.

Thread Continuity

The channel generates deterministic UUIDs for thread IDs:

DMs with privacy users - Use Signal’s source_uuid
DMs with regular users - Generate UUID from phone number
Groups - Generate UUID from group ID

This ensures conversation history persists across restarts and works with the agent’s maybe_hydrate_thread feature.

Status Updates

The channel sends status updates to Signal:

Typing Indicators

When the agent is thinking, a typing indicator is sent via sendTyping RPC.

Status Messages

ApprovalNeeded - Sends approval prompt with request ID
JobStarted - Notifies about sandbox jobs
AuthRequired - Extension authentication prompts
Tool execution - Shown in debug mode (toggle with /debug)

Debug Mode

Toggle verbose tool output with the /debug command:

You: /debug
Bot: Debug mode enabled. Tool execution will be shown in chat.

[Agent executes a tool]
Bot: ◯ Running tool: FileRead
     ● Tool 'FileRead' completed (success)
     Tool 'FileRead' result:
     File contents: ...

signal-cli JSON-RPC API

The channel uses signal-cli’s HTTP/JSON-RPC API:

Receive Messages (SSE)

GET /api/v1/events?account=+1234567890

Returns Server-Sent Events stream:

data: {"envelope":{"source":"+1234567890","dataMessage":{"message":"hello"}}}

Send Message

POST /api/v1/rpc
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "method": "send",
  "params": {
    "recipient": ["+1234567890"],
    "message": "Hello!",
    "account": "+1234567890"
  },
  "id": "uuid"
}

Send to Group

{
  "jsonrpc": "2.0",
  "method": "send",
  "params": {
    "groupId": "abc123",
    "message": "Hello group!",
    "account": "+1234567890"
  },
  "id": "uuid"
}

Troubleshooting

signal-cli daemon not running

# Check if daemon is running
curl http://127.0.0.1:8080/api/v1/check

# Should return 200 OK

Messages not received

Check SSE connection - Logs should show “Signal SSE connected”
Verify account - Ensure SIGNAL_ACCOUNT matches the daemon’s account
Check allowlist - Verify sender is in SIGNAL_ALLOW_FROM
Check policy - Ensure SIGNAL_DM_POLICY isn’t blocking messages

Pairing not working

Check policy - Ensure SIGNAL_DM_POLICY=pairing
HTTP allowlist - Verify the channel can send messages
Logs - Look for “Pairing request upserted” or “Failed to send pairing reply”

Group messages ignored

Check group policy - Ensure SIGNAL_GROUP_POLICY isn’t disabled
Group ID - Verify group is in SIGNAL_ALLOW_FROM_GROUPS
Sender allowlist - Check sender is in SIGNAL_GROUP_ALLOW_FROM (or SIGNAL_ALLOW_FROM if empty)

Attachments rejected

Ensure attachment paths are absolute
Verify paths are within ~/.ironclaw/ sandbox
Check file exists and is readable

High memory usage

The channel uses an LRU cache (10,000 entries) for reply targets. If you have millions of messages, consider restarting periodically.

Source Code

Implementation: ~/workspace/source/src/channels/signal.rs
HTTP helpers: ~/workspace/source/src/channels/http.rs

Example Usage

Simple DM

You: Hello
Bot: Hi! I'm your IronClaw agent. How can I help?

You: What's in my workspace?
Bot: [reads workspace]
     You have 3 files:
     - identity.md
     - daily/2026-03-03.md
     - memory/context.md

Group Chat

Alice: Hey @IronClaw, summarize this conversation
Bot: [reads group history]
     Here's a summary of the last 20 messages...

Bob: What were the action items?
Bot: Main action items:
     1. Alice: Update docs
     2. Bob: Fix CI pipeline
     3. Carol: Review PR #123

Debug Mode

You: /debug
Bot: Debug mode enabled. Tool execution will be shown in chat.

You: Read the README
Bot: ◯ Running tool: FileRead
     [reading /home/user/project/README.md]
     ● Tool 'FileRead' completed (success)
     Tool 'FileRead' result:
     # Project Title
     ...

​Features

​Prerequisites

​Setup

​1. Install signal-cli

​2. Register Signal Account

​3. Start signal-cli Daemon

​4. Configure IronClaw

​Configuration

​Configuration Options

​DM Policies

​open

​allowlist

​pairing (default)

​Group Policies

​disabled

​allowlist (default)

​open

​Pairing

​DM Pairing

​Commands

​Privacy Mode (UUID-based)

​Attachments

​Thread Continuity

​Status Updates

​Typing Indicators

​Status Messages

​Debug Mode

​signal-cli JSON-RPC API

​Receive Messages (SSE)

​Send Message

​Send to Group

​Troubleshooting

​signal-cli daemon not running

​Messages not received

​Pairing not working

​Group messages ignored

​Attachments rejected

​High memory usage

​Source Code

​Example Usage

​Simple DM

​Group Chat

​Debug Mode

Features

Prerequisites

Setup

1. Install signal-cli

2. Register Signal Account

3. Start signal-cli Daemon

4. Configure IronClaw

Configuration

Configuration Options

DM Policies

`open`

`allowlist`

`pairing` (default)

Group Policies

`disabled`

`allowlist` (default)

`open`

Pairing

DM Pairing

Commands

Privacy Mode (UUID-based)

Attachments

Thread Continuity

Status Updates

Typing Indicators

Status Messages

Debug Mode

signal-cli JSON-RPC API

Receive Messages (SSE)

Send Message

Send to Group

Troubleshooting

signal-cli daemon not running

Messages not received

Pairing not working

Group messages ignored

Attachments rejected

High memory usage

Source Code

Example Usage

Simple DM

Group Chat

Debug Mode