Lets Claude Code, Codex CLI and Antigravity message each other, with live push into open sessions.
Let Claude Code, Codex CLI and Antigravity (Gemini) message each other,
and land each message straight in the other agent's open session.
If it saves you time, a ⭐ helps other people find it.
Get started · See it work · How push works · Across machines · CLI · Security · Contributing
npx agent-intercom install
Using Claude Code only? Install it as a plugin instead:
/plugin install agent-intercom --marketplace iambashar/agent-intercom
On Claude Code older than 2.1.275: /plugin marketplace add iambashar/agent-intercom, then /plugin install agent-intercom@agent-intercom. The plugin also adds a skill that teaches Claude the mailbox conventions.
The npx command registers the MCP server with every CLI it finds. Restart them, and each agent gets three tools: mail_send, mail_check and mail_peers. Then ask in plain words:
You → Claude: Ask codex to review the diff in
src/parser.tsand wait for its answer.
Turn on live push so nobody has to poll. Install it globally, because the daemon needs a stable path:
npm i -g agent-intercom
agent-intercom install --push
install changes, per CLI| CLI | Registration | Extra for push |
|---|---|---|
| Claude Code | claude mcp add, user scope | nothing; uses Claude Code's peer socket |
| Codex CLI | a managed block in ~/.codex/config.toml (backed up first) | nothing; uses the Codex app-server daemon |
Antigravity (agy) | agy mcp add | a session hook in ~/.gemini/config/hooks.json |
Use --only claude|codex|gemini for one CLI, and --local to pin a git checkout instead of npx. agent-intercom uninstall removes all of it, including the push daemon.
[!NOTE] The old
geminiCLI no longer accepts personal Google AI Pro sign-ins; Google moved those users to the Antigravity CLI (agy). Its agent is namedgeminihere by default.
Neither agent polls. The request appears in Codex as a new turn the moment it is sent, and the reply lands in Claude the same way.
| Agent | Mailbox name | How a message reaches the open session |
|---|---|---|
claude | Claude Code's local peer-messaging socket, the channel SendMessage uses between sessions. Arrives labelled as from another session. | |
codex | The shared app-server daemon the Codex TUI runs on: turn/start, or turn/steer when a turn is already running. | |
gemini | agy agentapi send-message into the conversation. Each session registers itself once through a hook. | |
| Any other MCP client | anything | No push. It reads with mail_check, or blocks with mail_check(wait_seconds=300). |
| Tool | What it does |
|---|---|
mail_send(to, body, reply_to?) | Drop a message in another agent's inbox |
mail_check(wait_seconds?) | Read and consume your messages; with wait_seconds (max 300) it blocks until one arrives |
mail_peers() | List known agents |
sequenceDiagram
autonumber
participant C as Claude Code
participant M as ~/.agent-mail/codex/inbox
participant P as pushd
participant X as Codex CLI (open session)
C->>M: mail_send(to: "codex", body)
M-->>P: file appears (fs.watch, no polling)
P->>M: claim: rename to <id>.json.pushing
P->>X: turn/start with the message
X-->>P: turn accepted
P->>M: move to read/
Note over X: Codex works on it, then replies with mail_send(to: "claude")
Delivered once. The daemon renames a message before pushing it, and mail_check renames before reading. Whoever wins the rename delivers it.
Fails safe. A failed push puts the file back in the inbox and retries after 30 s. If no session is open, the message waits for mail_check.
Addressing. Pick a session with claude.<session-name>, codex.<thread-id-prefix> or gemini.<conversation-prefix>. Otherwise the most recently active session gets it, or the one named in ~/.agent-mail/routes.json:
{ "claude": "api-server", "codex": "019f018a" }
[!WARNING] Push relies on undocumented internals of all three CLIs, and an update can change them without notice. When that happens, pushes fail, get logged, and the mail falls back to the inbox. Protocol details: docs/live-push.md.
agent-intercom watch claude under the Monitor tool wakes the session when mail arrives.mail_check(wait_seconds=300).Agents on a machine with no shared filesystem, such as a GPU server or an HPC cluster, join over SSH with bridge.sh. It moves each message to the machine its recipient lives on, and pulled mail is pushed like any other.
BRIDGE_HOST=gpu-box REMOTE_AGENTS="claude-gpu" ./bridge.sh
flowchart LR
subgraph laptop["💻 Laptop"]
A[claude] & B[codex] & G[gemini]
end
subgraph gpu["🖥️ gpu-box"]
R[claude-gpu]
end
laptop <-- "bridge.sh · rsync over SSH" --> gpu
More: docs/remote-bridge.md.
Names are just AGENT_NAME. Give each session its own, for example claude-api and claude-web:
npx agent-intercom install --only claude --claude-name claude-api
agent-intercom install [--only claude|codex|gemini] [--claude-name N] [--codex-name N] [--gemini-name N] [--local] [--push]
agent-intercom uninstall MCP entries, agy hook and push daemon
agent-intercom push install push daemon as a login service (launchd / systemd --user)
agent-intercom push uninstall
agent-intercom push run push daemon in the foreground
agent-intercom status unread/read counts per agent
agent-intercom watch <name> one line per new message, without consuming it
agent-intercom serve the MCP server on stdio
This is a local mailbox with no authentication. Any process running as you can write to ~/.agent-mail/*/inbox, and an agent treats a message as input to act on. With push on, that input reaches your open sessions without you typing anything.
[agent-intercom] message <id> from <sender>. Claude Code also marks them as from another session, not from you.~/.claude/sessions/*.key, the agy session token) and talks only to local sockets. Nothing leaves the machine.See SECURITY.md to report a problem. Set AGENT_MAIL_DIR to move the mailbox, for example into a project folder.
Contributions are welcome, from a typo fix to support for a new agent.
| I want to… | Start here |
|---|---|
| Fix something small | Good first issues |
| Support another coding agent | docs/adding-an-agent.md |
| Report a push that broke after a CLI update | Bug report |
| Ask a question or pitch an idea | Discussions |
Read CONTRIBUTING.md before opening a pull request. Everyone here follows the code of conduct.
git clone https://github.com/iambashar/agent-intercom && cd agent-intercom
npm test # node --test, no dependencies
python3 scripts/build-assets.py # rebuild the README artwork
Zero runtime dependencies; Node 20+. See CONTRIBUTING.md and the changelog.
MIT licensed · made for people who run more than one coding agent
Source-derived launch command. Check the maintainer’s required arguments and credentials before running:
npx -y agent-intercomMerge this template into ~/Library/Application Support/Claude/claude_desktop_config.json. Keep existing servers. Add any arguments, credentials, and permissions required by the maintainer; this template has not been install-tested.
{
"mcpServers": {
"io-github-iambashar-agent-intercom": {
"command": "npx",
"args": [
"-y",
"agent-intercom"
]
}
}
}Restart Claude Desktop completely for changes to take effect. Confirm the server appears connected in the client’s tool list, then try a read-only example from its documentation.
Claude Desktop setup referenceagent-intercomnpmagent-intercom works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.
~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.~/.cursor/mcp.jsonRestart Cursor for changes to take effect..vscode/mcp.jsonReload VS Code window for changes to take effect.~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect..mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.