Session Persistence

yoyo can save and load conversations, letting you resume where you left off.

Auto-save on exit

yoyo automatically saves your conversation to .yoyo/last-session.json every time you exit the REPL — whether via /quit, /exit, Ctrl-D, or even unexpected termination. No flags needed.

If a previous session is detected on startup, yoyo prints a hint:

  💡 Previous session found. Use --continue or /load .yoyo/last-session.json to resume.

Resuming with --continue

The --continue (or -c) flag restores the last auto-saved session:

yoyo --continue
yoyo -c

--continue-strict behaves like --continue, but if the session file is missing or can't be parsed it prints error: --continue-strict: could not restore <path>: <reason> and exits 1 before any model call. Plain --continue only warns and starts a fresh conversation (exit 0), so scripts that need to know a run really continued should use the strict flag. With --output-format stream-json, a successful restore also emits {"type":"sessionRestored","messages":N} as the line right after the first agentStart. It is absent when nothing was restored (see piped mode).

--save-session <path> makes a non-interactive run (-p or piped stdin) write its session to <path> when it finishes — even if the turn failed — in the same format /save uses, so /load <path> resumes it. The parent directory must already exist; if the write fails yoyo prints error: --save-session: could not write <path>: <reason> and exits non-zero.

When --continue is used:

On startup, yoyo loads from .yoyo/last-session.json (preferred) or yoyo-session.json (legacy fallback)
On exit, the conversation is auto-saved as usual

$ yoyo -c
  📋 resumed session (8 messages, 5 tool calls)
  last prompt: "Can you fix the test failures in commands_map.rs?"
  last reply:  "I found 3 failing tests. The issue was..."

main > what were we working on?

Manual save/load

Save the current conversation:

/save

This writes to yoyo-session.json in the current directory.

Save to a custom path:

/save my-session.json

Load a conversation:

/load
/load my-session.json
/load .yoyo/last-session.json

Session format

Sessions are stored as JSON files containing the conversation message history. The format is determined by the yoagent library.

The `/todo` list travels with the session

The /todo list is session state, so it is saved and restored with the conversation. Every save path (/save, auto-save on exit, --save-session) writes the list to a sibling file named after the session with a .todos.json extension: .yoyo/last-session.json gets .yoyo/last-session.todos.json, and yoyo-session.json gets yoyo-session.todos.json. Every resume path (/load, --continue) reads it back, with the same IDs, descriptions and statuses.

Loading a session replaces the current list. A session saved before this existed, or saved with an empty list, has no sibling file and resumes with an empty list.
Saving with an empty list writes no sibling file and removes a stale one left at the same path, so old items can't come back.
If the sibling file can't be read or parsed, the resume still succeeds: yoyo prints one warning on stderr and starts with an empty list.
/todo board tasks are files under session_plan/ and are not part of this; only the session list is.

Error handling

If no previous session exists when using --continue, yoyo prints a message and starts fresh
If a session file is corrupt or can't be parsed, yoyo warns you and starts fresh
Empty conversations (no messages exchanged) are not auto-saved
Save errors are reported but don't crash yoyo

yoyo documentation