agterm-fork

agterm-fork

Only inside agterm, and only with the agterm-backup capture hook — that hook's live record is where a session's own claude id comes from.

agterm-fork                      # fork the current pane
agterm-fork <pane-id> [left|right]   # fork any pane (what the palette entry calls)
agterm-fork --dry-run            # print the plan, create nothing
agterm-fork install              # wire the "Fork session" custom command
agterm-fork uninstall            # remove it

The plugin's bin/ is on PATH inside a Claude Code session, so run it by name. What fork does:

1. Reads the pane out of agtermctl tree, refuses if no claude or codex runs there.
2. Session id: the agterm-backup live record, falling back to a --resume already in the pane's argv. Never guessed — no id, no fork.
3. Launch flags (--dangerously-skip-permissions, --model, …) are inherited from the parent's argv, minus --resume/--continue/--fork-session.
4. agtermctl session new --after <pane> — the anchor carries the workspace, so the fork lands next to its parent — then types claude --resume <id> --fork-session <flags> or, for codex, codex fork <id> <flags> (codex forks natively).
5. Waits for claude's "resume full session as-is / from summary" question and answers 2, so the fork really carries the whole history (--no-answer to skip).
6. Stops there. The fork gets no task; the user opens it and drives it.

install writes ~/.local/bin/agterm-fork and a managed block in ~/.config/agterm/keymap.conf:

command "Fork session" cmd+ctrl+a>f $HOME/.local/bin/agterm-fork "$AGT_SESSION_ID" "$AGT_PANE"

so cmd+ctrl+a>f, or Ctrl-Shift-O → "Fork session", forks whatever session the cursor is on, no Claude involved. The wrapper resolves the newest installed copy of the skill at call time, because the plugin cache path carries a commit sha and would otherwise break on every update.

Focus stays where it was (--no-select). The fork gets its own live record, so agterm-backup covers it like any other session.

A palette launch is detached with no terminal, so the wrapper writes that run to ~/.local/state/agterm-fork/palette.log (argv, PATH, socket, the script's output, exit code) and posts a "Fork session failed" notification when it exits non-zero. Read the log first when the palette entry seems to do nothing.