Switching projects

Ask to switch projects and the model calls fnc_switch_project. This session ends and fnclaude relaunches at the destination with a written summary of the conversation, so the new session starts already briefed.

This is the one that ends a session. To keep this one and open a second beside it, see Spawning siblings. To restart where you are, see fnc_restart in the Tool reference.

The countdown

The call ends the session, so the model warns you first. It prints a line like “Transferring in 3 seconds. Ctrl-C to cancel” and sleeps. If the sleep finishes, the switch fires. Interrupt it and nothing happens.

The summary that travels

Before calling, the model writes a summary of the conversation so far: what you asked for in your own words, the decisions made and why, the files read or edited, what is finished, what is still in flight, and any open questions. In-flight work is the part that matters most. It is what lets the new session pick up the thread instead of starting over.

With it goes a name, a three-to-six-word kebab-case topic such as fix-auth-bug, which labels the session at the destination.

What you pass

Say the destination the way you would say it out loud. The model passes it through verbatim and fnclaude’s resolver finds it, cloning if it has to:

# all valid destinations
arch-setup
arch-setup@fnrhombus
fnrhombus/arch-setup
https://github.com/fnrhombus/arch-setup
~/src/dots
arch-setup+fix-lid-sync

The full grammar is on Repo resolution.

If the request is ambiguous to the model, say “switch me to the other one” with no name, it asks which rather than guessing.

What carries over

The flags you started this session with carry over, minus a denylist of ones that belong to the old destination: --add-dir, --mcp-config, --from-pr, --name, and similar. The live permission mode is read from the session’s own log rather than assumed.

Ask for a change and the model overrides that one flag for the destination: model, effort, permission mode, allowed tools, agent, or the --brief, --chrome, --ide, and --verbose switches.

When auto-handoff is off

With auto-handoff disabled in config, the tool returns paste_flow instead of transferring. fnclaude renders the equivalent command and puts it on your clipboard, and you run it yourself.