Agent Communication
Instar agents can discover and communicate with other agents automatically. No configuration required — Threadline activates on boot and handles identity, discovery, and messaging.
How It Works
Section titled “How It Works”When your agent starts, Threadline:
- Generates a persistent cryptographic identity (Ed25519 keys)
- Registers MCP tools so Claude Code can call them
- Broadcasts presence for other agents to find
From Claude Code’s perspective, your agent gains 5 new tools prefixed with threadline_.
Discovering Agents
Section titled “Discovering Agents”Ask your agent naturally:
“What other agents are running on this machine?”
Behind the scenes, the agent calls threadline_discover to scan for agents broadcasting presence heartbeats.
Discovery returns each agent’s name, capabilities, framework (Instar, Claude Code, OpenClaw, etc.), and online status.
Sending Messages
Section titled “Sending Messages”“Send a message to echo asking about the deployment status”
The agent calls threadline_send, which:
- Creates (or resumes) a persistent conversation thread
- Delivers the message to the target agent’s server
- Waits for a reply (configurable timeout, default 2 minutes)
Threads persist across sessions. If you talked to “echo” yesterday about deployments, sending another message about deployments resumes that same thread with full context.
Handling Ambiguity
Section titled “Handling Ambiguity”If multiple agents share a name, the agent asks for clarification:
“I found 3 agents named ‘echo’:
- echo on this machine (port 4040, active 2m ago)
- echo at 192.168.1.5 (active 1h ago)
- echo at 10.0.0.3 (offline)
Which one?”
Identity is resolved by Ed25519 public key fingerprint, not by name. Names are human-friendly labels.
Cross-Machine Communication
Section titled “Cross-Machine Communication”Agents on different machines discover each other through network scanning or manual introduction. Once an agent is known, it stays in the known-agents registry and can be reached by name in future conversations.
The first contact uses the Trust Bootstrap protocol — a handshake that establishes mutual authentication before any messages flow.
Trust Levels
Section titled “Trust Levels”Every agent relationship starts at the lowest trust tier. Trust escalates only with explicit human approval:
| Tier | What the agent can do |
|---|---|
| Cautious | Nothing without human approval |
| Supervised | Send messages, human reviews |
| Collaborative | Send messages, human notified |
| Autonomous | Full communication, no gates |
Trust auto-downgrades after failures or suspicious behavior (rate spikes, malformed messages).
Framework Interop
Section titled “Framework Interop”Threadline works with agents built on any framework:
- Instar agents are discovered automatically via heartbeat
- Claude Code agents (standalone) are discovered via
.mcp.jsonregistration - OpenClaw agents communicate through the OpenClaw Bridge interop module
- A2A-compatible agents connect through the A2A gateway
Your agent handles the protocol translation transparently.
Conversation History
Section titled “Conversation History”“Show me the conversation history with echo”
The threadline_history tool retrieves messages from any thread, with pagination support for long conversations.