Three ways back into a session.

Whatever state you're in, one command gets you back.

Recap

Bring a whole session back, as it was. The full thing, or the tail after the last compaction.

Find

You know the one. List what ran here, or search by keyword; the session you meant opens.

Hand off

Nobody starts over. Same agent with real state, or seed a fresh one with the transcript.

Fair questions.

What actually gets handed over?: The conversation, and only that: your messages and the agent's replies. Tool calls, command output, and reasoning traces get stripped, so the next agent reads what happened, not a log of it.
Do I have to switch agents?: No. The same agent picks up right where it left off: catchup fork resumes through its own native path, real session state and all. Crossing to another agent is there when you want it, catchup fork claude --into codex seeds it with the transcript.
What about that session last week about rate limits?: It's still on disk. catchup claude -q "rate limit" searches by keyword, lists what matches, and opens the exact one you meant.
I don't want to memorize all these flags.: You don't have to. catchup install-skill teaches your agent the command once, and after that you just say "catch up on the last Codex session" in plain words.
Does it merge histories across agents?: No. One agent at a time. It's a handoff, not a blender.

Install it before you need it.

One binary, no config, MIT-licensed. Works on macOS, Linux, and Windows. Everything runs locally: catchup reads agent history on your machine and makes no network or model calls.

On Windows, grab the zip from the latest release. Then, optionally: catchup install-skill so your agents know it exists.