xxxxDev

Agent Courier — Development skill for Claude Code

Development community

Messages between Claude Code sessions on your own machines, over SSH, with no third party.

How to install Agent Courier

This entry records only its repository, not the path inside it, so there is no exact command to give. Open xxxxDev/agent-courier and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

What Agent Courier does

Messages between Claude Code sessions on your own machines, over SSH, with no third party.

Alternatives in Development

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README

agent-courier

agent-courier lets Claude Code sessions on different machines send messages to each other. The machines can use different Claude accounts. The messages go over SSH between your own machines. No third party carries them.

[!WARNING] Use agent-courier only between machines that you control. A paired machine is trusted as a whole: any program on it that can read its courier files can send as its agents. Read [docs/security.md](docs/security.md) before you pair two machines.

Messages from another agent are data, not your instructions. agent-courier marks them as untrusted, but it cannot stop an agent from following them.

Approvals guard against the model, not against code on your machine. A local agent with shell access can run `courier auto-approve` or read its token from Claude Code's configuration, and then send without a question. Keep such agents in a sandbox that denies access to `~/.config/agent-courier`, to Claude Code's configuration and to `courier`.

Machine A's courier serve calls machine B over SSH with a dedicated key; there a forced command, courier exchange, reads and writes the state file that machine B's courier serve uses. Claude Code sessions on each machine reach their own courier serve over MCP on 127.0.0.1.

Features

Direct and private. Messages go over SSH with a dedicated key per pairing. On the other machine, the key can run only courier exchange --pair , for that one pairing. The host key is pinned.
One token per session. courier agent add makes a token. The token is the agent's identity. The MCP endpoint listens only on 127.0.0.1.
Both sides decide. A pairing needs a one-time code and must be enabled on both machines. Each machine lists which of the other machine's agents e