Pi Intercom

Agent Intercom is a cross-harness, same-machine messaging system for coding agents. Its Pi, Codex, Claude Code, and OpenCode adapters share one local broker and protocol, so sessions can discover and message each other regardless of which harness they run in.

Harness	Repository
Pi	agent-intercom-pi
Codex	agent-intercom-codex
Claude Code	agent-intercom-claude
OpenCode	agent-intercom-opencode
Fleet lifecycle	agent-intercom-orchestrator

Origin and thanks

Agent Intercom grew from Nico Bailon's original pi-intercom. A sincere thank you to Nico and the original contributors for creating the Pi extension and the foundation this cross-harness family builds on.

This repository contains the native Pi adapter. It provides direct 1:1 messaging, overlays, keyboard shortcuts, and agent tools while interoperating with Codex, Claude Code, and OpenCode sessions on the same machine.

User flow: press Alt+M or run /intercom to pick a session and send a message

Why

Sometimes you're running multiple pi sessions — one researching, one executing, one reviewing. Pi-intercom lets you:

• User-driven orchestration — Send context or findings from your research session to your execution session
• Agent collaboration — An agent can reach out to another session when it needs help or wants to share results
• Session awareness — See what other pi sessions are running and their current status

Unlike pi-messenger (a shared chat room for multi-agent swarms), pi-intercom is for targeted 1:1 communication where you pick the recipient.

Pi-intercom also integrates well with pi-subagents: delegated child agents get a child-only contact_supervisor tool when pi-subagents supplies bridge metadata. Use reason: "need_decision" for blocking clarification, reason: "interview_request" for multiple structured supervisor answers, and reason: "progress_update" for meaningful plan-changing updates. Normal sessions only see the regular intercom tool.

In One Minute

Each pi session that has pi-intercom loaded and enabled connects to a tiny local broker over a local IPC transport. The broker keeps track of connected sessions and routes direct messages to the one you target by name or session ID. The extension gives you both a tool (intercom) and a small overlay UI (/intercom or Alt+M). Incoming messages are rendered inline inside the recipient session, can trigger a turn immediately by default, and are also stored in Pi session history as extension entries. If you want a stricter local trust posture, inboundTrigger can reduce or disable auto-triggering.

Install

pi install npm:@dataforxyz/agent-intercom-pi

For a Git-pinned install instead:

pi install git:github.com/dataforxyz/agent-intercom-pi@v0.9.1

Then restart Pi. The extension auto-connects to the broker on startup and registers the bundled pi-intercom skill for common coordination patterns.

To let Pi create and safely own persistent Pi, Codex, Claude Code, and OpenCode coworkers, install the companion orchestrator Pi plugin too:

pi install npm:@dataforxyz/agent-intercom-orchestrator

Restart Pi or run /reload, then verify:

agent_fleet({ action: "doctor" })
agent_fleet({ action: "capabilities" })

The orchestrator package adds the agent_fleet tool, /agents* commands, a scoped worker footer, and its manager Agent Skill. It uses exact systemd user-service cgroups, leases, adoption, and verified descendant cleanup. Linux with a working systemd user manager is required. Intercom handles communication; the orchestrator handles worker ownership and lifecycle, so most fleet-manager setups should install both packages.

Pi loads the Intercom extension directly, including its native Alt+I contact-copy shortcut, so no wrapper command or shell alias is required. You can still alias your usual Pi invocation for convenience, but unlike adapters that need a wrapper to add terminal behavior, an alias does not enable any additional pi-intercom features.

Pi-intercom is also protocol-compatible with the companion Codex, Claude, and OpenCode adapters. They share the same local broker and runtime directory, so sessions from all four hosts appear in the same session list and can send, ask, reply, and recover messages across host boundaries. The first connected adapter can start the broker; Pi does not need to be launched first.

Recommended: Add this snippet to your project's AGENTS.md to help agents understand when to coordinate across sessions:

<pi-intercom>
Coordinate with other local Agent Intercom sessions across Pi, Codex, Claude Code, and OpenCode. Use `/skill:pi-intercom` for patterns.

**When:** Same codebase (parallel work), reference codebase (consulting patterns), related repos (shared libraries).

**Not when:** Unrelated codebases, trivial questions, or when you can proceed independently.

**Principle:** Prefer `send` for notifications; `ask` only when blocked waiting for input.
</pi-intercom>

A session becomes intercom-connected when all of these are true:

• the pi-intercom extension is installed and loaded in that session
• enabled is not set to false in the intercom config file, which defaults to ~/.pi/agent/intercom/config.json
• the session has started or reloaded after the extension was installed
• the local broker is running or can be auto-started

The session list only shows intercom-connected sessions, not every open Pi process on the machine.

If you upgrade pi-intercom or the orchestrator while sessions are already open, run /reload in each open Pi session (and restart any companion coi, cci, or OpenCode adapter). Update the packages with pi update --extension npm:@dataforxyz/agent-intercom-pi and pi update --extension npm:@dataforxyz/agent-intercom-orchestrator. Extensions are loaded into the running host process, so an existing session cannot adopt new broker/discovery code until it reloads. This is especially important when upgrading from a release that allowed multiple broker processes to form separate session-list "islands": the broker ownership fix prevents new splits, but it cannot move clients that are still running the old code. After every host has reloaded once, they converge on the same broker automatically.

If /intercom still reports no peers, first confirm the other Pi windows have pi-intercom loaded and have also been reloaded. Open Pi processes without the extension, disabled sessions, and sessions using a different PI_CODING_AGENT_DIR intentionally do not appear in the same list.

If a session is unnamed, pi-intercom now exposes a runtime-only fallback alias like subagent-chat-1a2b3c4d so other sessions can still target it. That alias is not persisted as the Pi session title, so pi --resume can keep showing the transcript snippet instead of a generic session-... name.

Quick Start

Common Interface Across Hosts

The intercom packages use the same keyboard convention wherever the host exposes the required terminal hooks:

Action	Pi	Codex (coi)	Claude (cci/ccim)	OpenCode
Pick a session and send	/intercom or Alt+M	Alt+M	/claude-intercom:intercom or Alt+M	/intercom or Alt+M
Copy this session's contact target	/intercom-id or Alt+I	Alt+I	/claude-intercom:intercom-id or Alt+I	/intercom-id or Alt+I

Codex does not currently expose a native custom slash-command API, so its coi wrapper provides the shared keyboard shortcuts instead. Claude namespaces installed plugin commands and its terminal shortcuts require the attached cci or ccim wrapper. For those adapters, a shell alias is recommended because it makes the wrapper the normal launch command and ensures the shortcuts and wakeable intercom behavior are present. Pi loads those features natively, so an alias is optional here.

The contact text copied by Alt+I or /intercom-id is deliberately host-neutral. Paste it into any supported agent to identify the exact target without requiring that agent to look the session up by a machine-specific path or transient display label.

From the Keyboard

Press Alt+M or type /intercom to open the session list overlay:

1. Select a session — Use arrow keys to pick a target session
2. Find and select — Start typing to filter long session lists
3. Compose message — Write or paste a multiline message; use Shift+Enter for a newline
4. Send — Press Enter to send, Escape to cancel

Press Alt+I or run /intercom-id to copy a short handoff snippet for the current session. The snippet uses the session's unique name when possible, falling back to the stable intercom session ID when names are duplicated.

From the Agent

The agent uses seven focused tools: intercom_send, intercom_ask, intercom_reply, intercom_team, intercom_list, intercom_pending, and intercom_status. Tool calls and results render as compact transcript rows so coordination is easy to scan. For common patterns like planner-worker delegation, the bundled pi-intercom skill provides copy-paste ready examples:

// Find the manager and managed coworkers without searching the global list
intercom_team({})
// → Manager: manager-id [connected]
// → You: reviewer
// → Coworkers: builder target=builder (codex, builder, running) [connected]

// List all active sessions
intercom_list({})
// → **Current session:**
// → • executor (20d43841) — ~/projects/api (claude-sonnet-4) [self, idle]
// → **Other sessions:**
// → • research (6332faab) — ~/projects/api (claude-sonnet-4) [same cwd, thinking]

// Send a message
intercom_send({ to: "research", message: "Check if UserService.validate() handles null" })
// → Message sent to research

// Check connection status
intercom_status({})
// → Connected: Yes, Session ID: abc123, Active sessions: 3

// Send with attachments (code snippets, files, or context)
intercom_send({
  to: "worker",
  message: "Here's the fix:",
  attachments: [{
    type: "snippet",
    name: "auth.ts",
    language: "typescript",
    content: "function validate(user: User) { ... }"
  }]
})

Receiving Messages

When a message arrives, it appears inline in your chat with the sender's info and a reply hint:

**From research** (~/projects/api)

To reply, use the intercom tool: intercom_reply({ message: "..." })

Found the issue — UserService.validate() doesn't check for null input.
See auth.ts:142-156.

The reply hint (enabled by default) points to intercom_reply({ ... }), so recipients never need protocol thread IDs. Incoming messages are first written to a durable per-session inbox. Messages arriving within a 300 ms quiet window are combined into one model turn, with a 1-second maximum batching delay so a steady stream cannot postpone delivery forever. Busy sessions keep the batch queued until they are idle. Every original sender, message ID, timestamp, attachment, and reply context remains available in the batch details.

The sender receives two distinct delivery states in structured tool details: accepted means the broker accepted the message for routing, while delivered means the receiver durably queued it and acknowledged the delivery. Outbound messages are also written to a durable per-session outbox before transmission. If the broker disconnects between acceptance and receiver acknowledgement, the next connection automatically replays the original target, payload, and message ID. Attachment content is included in the agent-visible body, and delivered messages are rendered inline and stored in Pi session history.

Workflow: Planner-Worker Coordination

The most natural use of pi-intercom is splitting a task between two sessions — one holds the big picture, the other does the hands-on work. When the worker hits an ambiguity ("should I optimize for readability or performance here?"), they ask without losing context.

Setup

Open two terminals and start pi in each. Name them so they can find each other:

# Terminal 1                    # Terminal 2
/name planner                   /name worker

Verify they see each other from either session:

intercom_list({})
// → • worker — ~/projects/api (claude-sonnet-4) [idle]

The Conversation

Here's how a typical exchange looks. The planner delegates with send (fire-and-forget). The worker uses ask for anything that needs a response — questions, discoveries, completion reports. ask waits up to 30 seconds so a prompt answer can return in the same tool result, then releases the worker and delivers any late answer as a new intercom message.

Planner sends a task:

intercom_send({
  to: "worker",
  message: "Task-3: Add retry logic to API client. Key files: src/api/client.ts, src/api/types.ts. Ask if anything's unclear."
})

Worker hits an ambiguity — asks and waits:

intercom_ask({
  to: "planner",
  message: "Should retry apply to all endpoints or just idempotent ones? Also, max retry count and backoff strategy?"
})
// → Reply from planner: Only GET/PUT/DELETE — never POST. Max 3 retries, exponential backoff starting at 100ms.
// Worker continues implementing with the answer, same turn, full context.

Worker finds something unexpected — escalates and waits:

intercom_ask({
  to: "planner",
  message: "Found: fetchWithTimeout swallows network errors. Fixing this changes the error shape. OK to proceed?"
})
// → Reply from planner: Yes, surface the error types. The current behavior is a bug.

Worker reports completion:

intercom_ask({
  to: "planner",
  message: "Task-3 done. Added RetryPolicy type, applied to GET/PUT/DELETE, surfaced NetworkError, 4 tests passing."
})
// → Reply from planner: Looks good. Move on to task-4.

Communication Patterns

Pattern	Action	Why
Task Delegation	Planner uses send	Fire-and-forget. Planner doesn't need to wait for an ack.
Clarification Request	Worker uses ask	Worker needs the answer to proceed. Blocks until reply.
Discovery Escalation	Worker uses ask	Worker needs approval before changing course.
Completion Report	Worker uses ask	Planner might have follow-up instructions or the next task.

Reply Hints

When replyHint is enabled (the default), incoming messages include the exact intercom_reply() call to respond:

**From planner** (~/projects/api)

To reply, use the intercom tool: intercom_reply({ message: "..." })

Only GET/PUT/DELETE — never POST. Max 3 retries with exponential backoff starting at 100ms.

This matters because the agent receiving the message never needs to see or reconstruct protocol thread IDs. Combined with idle-gated triggerTurn delivery, it enables real back-and-forth conversation without interrupting work in progress. If the reply happens later instead of in the triggered turn, intercom_reply({ message: "..." }) falls back to the single unresolved inbound ask, and intercom_pending({}) shows who is still waiting.

send vs ask

intercom_send is non-blocking with respect to a reply: it waits only for the receiver's durable-enqueue acknowledgement, then returns. By default, it sends immediately even in interactive sessions. If you want an approval dialog before non-reply sends, set confirmSend: true in config. intercom_reply skips confirmation so reply-hint flows can continue without an extra approval step.

intercom_ask sends the message and waits up to 30 seconds for the recipient. A prompt reply comes back as the tool result, so the agent continues in the same turn with full context. If nobody replies within 30 seconds, the tool returns control without an error and keeps the request open asynchronously; a late reply arrives as a new intercom message. No confirmation dialog — if you're asking and waiting, the intent is clear.

intercom_reply is receiver-side sugar for replying to an inbound ask. In the turn triggered by an incoming intercom ask, intercom_reply({ message: "..." }) targets that exact sender and message automatically. If you reply later, it falls back to the single unresolved inbound ask. If multiple asks are pending, use intercom_pending({}) to inspect them and then call intercom_reply with to to select the sender.

The planner typically uses send. If you prefer manual approval for outgoing non-reply messages, turn on confirmSend: true. The worker uses ask for everything (no confirmation needed, gets answers inline), so it can operate autonomously either way.

Workflow: Subagent-to-Supervisor Escalation

This workflow requires pi-subagents to be installed and to supply child bridge metadata. When pi-subagents spawns a delegated child with that metadata, the child session gets a subagent-only contact_supervisor tool in addition to the regular intercom tool. Normal sessions never see contact_supervisor.

When the Tool Appears

contact_supervisor only registers when pi-subagents sets all of these environment variables:

• PI_SUBAGENT_ORCHESTRATOR_TARGET — the supervisor session name or ID
• PI_SUBAGENT_RUN_ID — the run identifier
• PI_SUBAGENT_CHILD_AGENT — the agent type
• PI_SUBAGENT_CHILD_INDEX — the child index within the run

If any are missing, the session falls back to the regular intercom tool.

Three Reasons

Reason	Behavior	Use When
need_decision	Waits up to 30 seconds, then continues asynchronously if unanswered	The subagent is blocked, uncertain, needs approval, or faces a product/API/scope decision
interview_request	Waits up to 30 seconds for structured answers, then continues asynchronously	The subagent needs multiple machine-readable answers from the supervisor in one exchange
progress_update	Fire-and-forget update to the supervisor	Meaningful progress or unexpected discoveries that change the plan

Do not use contact_supervisor for routine completion handoffs. Return the final subagent result normally through pi-subagents.

Example: Blocked Subagent Asks for Guidance

contact_supervisor({
  reason: "need_decision",
  message: "The auth service returns 403 instead of 401 for expired tokens. Should I treat 403 as a re-auth trigger or a hard failure?"
})
// → Reply from supervisor: Treat 403 as re-auth trigger. Update the token refresh logic.

Example: Structured Supervisor Interview

contact_supervisor({
  reason: "interview_request",
  message: "Please answer these before I continue the migration.",
  interview: {
    title: "API migration choices",
    questions: [
      { id: "api", type: "single", question: "Which API should I target?", options: ["Stable API", "Experimental API"] },
      { id: "constraints", type: "text", question: "What constraints should I preserve?" }
    ]
  }
})
// → Reply from supervisor: { "responses": [{ "id": "api", "value": "Stable API" }, ...] }

Example: Progress Update

contact_supervisor({
  reason: "progress_update",
  message: "Discovered the bug is in the retry wrapper, not the API client. Fixing the wrapper will also close issue #42."
})
// → Progress update sent to supervisor planner

What the Supervisor Sees

The supervisor receives a formatted message with run metadata:

**From subagent-worker-78f659a3-1**

Subagent needs a supervisor decision.
Run: 78f659a3
Agent: worker
Child index: 0

Which API should I use?

Reply hints work the same as regular intercom_ask/intercom_reply flows. The supervisor can reply with intercom_reply({ message: "..." }) and the subagent receives the answer as the tool result.

For interview_request, the supervisor message includes the structured questions plus a fenced JSON answer example using this stable shape:

{
  "responses": [
    { "id": "api", "value": "Stable API" },
    { "id": "constraints", "value": "Keep the public error shape unchanged." }
  ]
}

The supervisor can reply with plain JSON or a fenced json block. If the reply matches the { "responses": [...] } shape and references valid question ids/options, the child tool result includes it in details.structuredReply while still showing the raw reply text.

Tool Reference

Split intercom tools

Tool	Parameters	Description
intercom_send	required to, required message, optional attachments	Fire-and-forget delivery
intercom_ask	required to, required message, optional attachments	Ask and wait briefly for a reply
intercom_reply	required message, optional to	Reply to the active or pending inbound message; to selects a sender when multiple asks are pending
intercom_team	none	Show the current manager and live coworkers owned by that manager
intercom_list	none	List connected sessions globally
intercom_pending	none	List unresolved inbound asks
intercom_status	none	Show connection and queue status

Exact reply threading is internal. No split tool exposes replyTo, reply_to, or any message/thread-ID parameter.

contact_supervisor

Only registered in sessions where pi-subagents supplied the required child bridge metadata. Contacts the supervisor session that delegated the current task.

Parameter	Type	Description
reason	string	"need_decision" (soft-waiting), "interview_request" (soft-waiting structured questions), or "progress_update" (fire-and-forget)
message	string	The decision request, optional interview note, or progress update
interview	object	Required for interview_request: { title?, description?, questions: [...] }

need_decision — Sends a formatted ask to the supervisor and waits up to 30 seconds. A prompt reply comes back as the tool result; otherwise the request remains open and a late reply arrives asynchronously. Includes run metadata in the message so the supervisor knows which subagent is asking.

interview_request — Sends a formatted, agent-readable interview to the supervisor and waits up to 30 seconds. Questions use a local pi-interview-like shape: { id, type, question, options?, context? } where type is single, multi, text, image, or info. info questions are context-only and do not need responses. The supervisor reply should be JSON with { "responses": [{ "id": "...", "value": ... }] }. Prompt parsed replies are returned in details.structuredReply; late replies arrive asynchronously.

progress_update — Sends a non-blocking update to the supervisor. Returns immediately after delivery. Use only for meaningful progress or unexpected discoveries that change the plan.

Tool behavior

intercom_team reads orchestrator ownership dynamically and returns the current manager plus live same-manager coworkers. After adoption it follows the new manager without restarting the worker; AGENT_INTERCOM_MANAGER_TARGET is only a startup fallback.

intercom_list returns the current session plus other active intercom-connected sessions with name, short ID, working directory, model, and live status. It is global, so orchestrator-owned workers should prefer intercom_team for their group.

intercom_send sends immediately and distinguishes broker accepted from receiver-acknowledged delivered. Set confirmSend: true for an interactive confirmation dialog.

intercom_ask waits up to 30 seconds for a prompt reply, then returns a successful pending result while keeping the request open for a late reply. PI_INTERCOM_ASK_WAIT_MS changes the blocking window.

intercom_reply resolves the active or pending inbound context internally. Pass optional to only to select a sender when multiple asks are pending; it is never a thread or message ID. If multiple unresolved asks from the same sender remain after their original turns, sender-only disambiguation is intentionally unavailable; answer them while their inbound turn context is active or ask the sender to resend the specific question.

intercom_pending lists unresolved inbound asks with sender, elapsed time, and a preview.

intercom_status shows connection, session, queue, and pending-ask status.

The deprecated monolithic intercom({ action: ... }) tool is hidden by default. Enable legacyTool only for temporary compatibility.

Keyboard Shortcuts

Key	Action
Alt+M	Open session list overlay
Alt+I	Copy this session's intercom contact target, falling back to editor insert
↑/↓	Navigate session list
Enter	Select session / Send message
Shift+Enter	Insert a newline while composing
Escape	Cancel / Close overlay

The session picker is searchable, multiline bracketed paste is preserved, and displayed session metadata is sanitized before it reaches the terminal.

Config

Create ~/.pi/agent/intercom/config.json:

{
  "brokerCommand": "npx",
  "brokerArgs": ["--no-install", "tsx"],
  "confirmSend": false,
  "inboundTrigger": "always",
  "enabled": true,
  "replyHint": true,
  "legacyTool": false,
  "status": "researching"
}

Setting	Default	Description
brokerCommand	"npx"	Advanced trusted override for the broker executable. The default value is hardened internally to launch the resolved bundled tsx CLI through the current Node executable instead of resolving npx through PATH.
brokerArgs	["--no-install", "tsx"]	Advanced trusted arguments passed to custom brokerCommand before the broker script path
confirmSend	false	Show a confirmation dialog before non-reply sends from an interactive session with UI
inboundTrigger	"always"	Auto-trigger policy for inbound broker messages: "always", "replies", or "never". Local in-process subagent relay events still trigger the addressed session.
enabled	true	Enable/disable intercom entirely
replyHint	true	Include reply instruction in incoming messages
legacyTool	false	Expose the deprecated monolithic intercom({ action: ... }) tool. Compatibility only; can also be enabled with PI_INTERCOM_LEGACY_TOOL=1, and scheduled for removal at the next major boundary.
status	—	Optional custom status suffix shown after the automatic lifecycle status, for example thinking · researching

If config.json cannot be parsed or contains an invalid value, pi-intercom logs the error and fails closed for inbound broker auto-triggering by using inboundTrigger: "never" until the config is fixed.

Custom broker commands are trusted local configuration: anyone who can edit this config can choose the executable used for future broker auto-spawns. For example, if you have Bun installed and want it to start the broker directly, use:

{
  "brokerCommand": "bun",
  "brokerArgs": []
}

Pi-intercom publishes live session status automatically. Sessions register as idle, switch to thinking while the agent is running, show tool:<name> during tool execution, and return to idle on agent completion. If status is set in config, it is appended as context instead of replacing the lifecycle status.

By default, runtime state and config live under ~/.pi/agent/intercom. If Pi is launched with PI_CODING_AGENT_DIR, pi-intercom uses $PI_CODING_AGENT_DIR/intercom instead, including config.json, broker PID/lock files, sockets, durable inboxes/outboxes, ask state, and launcher state. PI_INTERCOM_ASK_WAIT_MS controls the foreground ask wait (30 seconds by default); PI_INTERCOM_ASK_TIMEOUT_MS controls how long a deferred ask remains replyable (10 minutes by default).

How It Works

graph TB
    subgraph A["Pi Session A"]
        A1[Intercom Client]
        A2[intercom tool]
        A3[UI overlays]
    end

    subgraph Broker["Intercom Broker"]
        B1[Session Registry]
        B2[Message Router]
    end

    subgraph B["Pi Session B"]
        B3[Intercom Client]
        B4[intercom tool]
        B5[UI overlays]
    end

    A1 <-->|Local Socket/Pipe| B1
    B1 --- B2
    B2 <-->|Local Socket/Pipe| B3

The broker is a standalone TypeScript process that manages session registration and message routing. It auto-spawns when the first intercom-enabled session needs it and exits after 5 seconds when the last connected session disconnects. Clients now reconnect automatically if the broker disappears and later comes back.

Messages use strict pi-intercom protocol v3 over length-prefixed JSON on a local socket/pipe transport (4-byte length + JSON payload). Registration rejects incompatible protocol versions instead of attempting a partially compatible connection. The protocol includes request correlation, structured error codes, delivery IDs, receiver acknowledgements and rejections, retry deduplication by sender session plus message ID, acknowledged ask controls, payload and pending-work bounds, a frame-size cap, byte-weighted per-connection rate limiting, and no-op presence coalescing.

The receiver acknowledges only after atomically writing the message to its per-session inbox. Delivery is therefore at least once across reconnects and reloads. There is one narrow crash window after a batch is injected into Pi but before its inbox entries are marked consumed; after recovery, that batch can be shown again rather than silently lost.

Session IDs are the trusted addressing key. Duplicate names remain allowed for same-user workflows, but sends to ambiguous names fail and users should target the stable session ID shown by list/status in trust-sensitive flows. The broker owns local trust metadata such as trustedLocal; peerUid is reserved for runtimes that can expose real peer credentials and is left unset otherwise. Client-supplied cwd/model/pid/status are display metadata, not authentication.

Async extension work (startup, inbound flushes, reconnects, overlays, and relays) no-ops if the session shuts down or reloads before it settles.

Runtime files live at ~/.pi/agent/intercom/ by default, or $PI_CODING_AGENT_DIR/intercom/ when PI_CODING_AGENT_DIR is set:

• broker.sock — Unix domain socket for communication (macOS/Linux only; Windows uses a named pipe instead)
• broker-launch.vbs — Windows helper script used to launch the broker without a console window
• broker.pid — Broker process ID
• broker.owner — Lifetime ownership record that prevents another live broker from replacing the active socket
• broker.spawn.lock — Auto-spawn lock file
• broker.port.json — Dynamic localhost TCP endpoint, only when Windows TCP transport is explicitly enabled
• broker-asks.json — Expiring ask/reply authorization edges; restored as deferred after broker restart
• config.json — User configuration
• inbox/<session-hash>.json — Durable ordered inbound messages and receiver-side deduplication state
• outbox/<session-hash>.json — Durable unfinished outbound messages replayed after reconnect

Design Decisions

Local IPC instead of TCP. Same-machine only by design. pi-intercom uses Unix sockets on macOS/Linux and a named pipe on Windows, which keeps setup simple and avoids port management. Windows TCP is available only as an explicit escape hatch with PI_INTERCOM_TRANSPORT=tcp (or PI_INTERCOM_TCP=1) for environments where named pipes are blocked. In that mode the broker binds a dynamic 127.0.0.1 port, records the endpoint plus a local secret under the intercom state dir, and requires that secret before health or registration succeeds. Health replies do not echo the secret, so a random localhost process cannot discover it through the broker protocol.

Auto-spawn with two levels of ownership. The broker starts on first connection and exits after 5 seconds idle. There is no daemon to manage. A short-lived spawn lock, keyed by PID and timestamp, coordinates clients that try to start the broker at the same time. A separate lifetime ownership record prevents any second live broker process from unlinking or replacing the active socket, including brokers launched manually or by different host adapters.

ask has a soft foreground wait. The client waits up to 30 seconds for a matching reply and returns a prompt reply as the tool result. After that soft wait expires, the sender continues and asks the broker to change the edge from blocking to deferred. That control operation is explicitly acknowledged. Deferred asks permit reverse asks, remain late-replyable until the 10-minute expiry, and survive broker restart without recreating a blocking dependency. Reply hints make the flow practical by preserving the exact reply context.

pi-intercom vs pi-messenger

Aspect	pi-intercom	pi-messenger
Model	Direct 1:1 messaging	Shared chat room
Primary use	User orchestrating sessions	Autonomous agent coordination
Discovery	Broker-based (real-time)	File-based registry
Messages	Private, session-to-session	Broadcast to all agents
Persistence	Durable delivery inbox plus Pi session history	Shared coordination files

Use pi-messenger for multi-agent swarms working on a shared task. Use pi-intercom when you want to manually coordinate your own sessions or have one agent reach out to another specific session.

File Structure

~/.pi/agent/extensions/pi-intercom/
├── package.json
├── index.ts              # Extension entry point
├── types.ts              # SessionInfo, Message, protocol types
├── config.ts             # Config loading
├── durable-json.ts       # Atomic fsync-backed JSON persistence helper
├── inbound-inbox.ts      # Durable inbound queue and deduplication
├── outbound-outbox.ts    # Durable sender replay queue
├── broker/
│   ├── broker.ts         # Broker process
│   ├── client.ts         # IntercomClient class
│   ├── framing.ts        # Length-prefixed JSON protocol
│   ├── paths.ts          # Platform-specific socket/pipe paths
│   ├── spawn.ts          # Auto-spawn logic with lock file
│   ├── spawn.test.ts     # Broker spawn tests
│   └── paths.test.ts     # Path resolution tests
├── ui/
│   ├── session-list.ts   # Session selection overlay
│   ├── compose.ts        # Message composition overlay
│   ├── inline-message.ts # Received message display
│   └── session-identity.ts # Unique prefixes and safe display metadata
└── skills/
    └── pi-intercom/
        └── SKILL.md      # Bundled skill for common patterns

Limitations

• Same machine only — Uses local sockets/pipes, no network support
• No separate transcript UI — Messages are kept in Pi session history and a durable delivery inbox, but there is no standalone inbox browser
• No attachments UI — file, snippet, and context attachments are supported in the protocol, but not in the compose overlay
• Only connected sessions appear — The list shows Pi sessions that have loaded pi-intercom and successfully registered with the broker, not every open Pi process on the machine
• Broker lifecycle — The broker auto-spawns on first use and exits when idle; sessions reconnect automatically if the broker restarts
• At-least-once recovery — A crash in the small interval between Pi injection and inbox consumption can replay a batch after restart
• Bounded sender queue — Each session keeps at most 256 unfinished outbound messages; definitive delivery failures are removed rather than retried forever

Releasing

Releases are automated from version tags. Update package.json, the lockfile when present, and CHANGELOG.md on main, then push an annotated tag that exactly matches the package version:

git tag -a vX.Y.Z -m "vX.Y.Z"
git push origin vX.Y.Z

The release workflow verifies that the tag points into main, runs typecheck and tests, publishes the public npm package with trusted OIDC provenance, and creates the GitHub Release. Existing npm versions and GitHub Releases are skipped safely when a workflow is rerun.

License

The current project is licensed under the GNU Affero General Public License v3.0 or later (AGPL-3.0-or-later). If you modify this software and make the modified version available to users over a network, the AGPL requires you to offer those users the corresponding source code.

Portions derived from the original MIT-licensed pi-intercom project retain their original notices. See THIRD_PARTY_NOTICES.md and licenses/MIT-pi-intercom.txt. Versions already published under MIT remain available under their original terms. See LICENSE_TRANSITION.md for the exact commit and tag boundary.