docs: describe what a rolled-back turn keeps

A failed or cancelled turn drops unfinished assistant text, and tool calls
whose result already arrived stay in history (and in the store), so /retry
continues from real results instead of running those tools again.

AGENTS.md

@@ -118,7 +118,7 @@ Click app + readline REPL. Entry: `plyngent` / `python -m plyngent`.
 - `/btw` side questions: forked session; main transcript/DB untouched. `--tools=read` (default) exposes only `READ_ONLY` tools under `read_only_context()` (fetch=GET) with the main session view; `--tools=no` off; `--tools=full` whole-registry clone with fresh session. Tools off: default falls back to no tools; explicit `read`/`full` errors. The model gets an `aside` notice as its last message before the question (unsaved exchange + tool scope), shown to the user as `[notice] aside: …`.
 - Explicit `/resume` or `--session` from another workspace prompts: **keep** / **update** / **abort**. A session resumed by a **freshly started process** (`--session` / default latest) also gets a `resume` notice about what a restart drops (PTY sessions, running commands, temp workspaces) — resuming inside a live process pushes nothing.
 - Host notices (`agent/notices.py`): system-level messages appended as trailing `developer` rows, never system-prompt edits — `Notice.to_message()` for the model, `.summary` for the user via `cli.display.echo_notice` (`--quiet` hides the user line only). Durable hosts persist them (`ChatAgent.push_notice`); a side agent without memory keeps its notice local. Trailing developer messages never end a turn, so `/retry` still sees an interrupted turn behind a notice or checkpoint.
-- Failed/cancelled turns: user kept; **committed tool rounds kept** (side effects not re-run on `/retry`); only unfinished assistant rolled back; Ctrl+C cancels the in-flight turn (a session-scoped asyncio SIGINT handler routes it, `cli/interrupt.py` — a stray Ctrl+C while the loop waits never tears the REPL down); TTY confirms/ask prompts run off-loop and register their own SIGINT target, so Ctrl+C there cancels just the poll-based read (`wait` reports `cancelled by user`) or is ignored with a hint for readline prompts (`ask_user_*`, confirms) — never the turn, never the loop; auto-retry waits 5s/10s/15s/20s then +10s (10 attempts), its countdown is Ctrl+C-cancellable, and the budget **resets when an attempt completes a model round** (connection recovered); then `/retry`.
+- Failed/cancelled turns: user kept; **committed tool rounds kept**, and a batch cut short keeps the calls that already produced a result (`rollback_tail`; written to the store, so a resume continues from them instead of re-running them) — side effects are not re-run on `/retry`, and only unfinished assistant text is dropped; Ctrl+C cancels the in-flight turn (a session-scoped asyncio SIGINT handler routes it, `cli/interrupt.py` — a stray Ctrl+C while the loop waits never tears the REPL down); TTY confirms/ask prompts run off-loop and register their own SIGINT target, so Ctrl+C there cancels just the poll-based read (`wait` reports `cancelled by user`) or is ignored with a hint for readline prompts (`ask_user_*`, confirms) — never the turn, never the loop; auto-retry waits 5s/10s/15s/20s then +10s (10 attempts), its countdown is Ctrl+C-cancellable, and the budget **resets when an attempt completes a model round** (connection recovered); then `/retry`.
 - Pretty tool lines: every builtin tool prints its `* Verb 'target' ` prefix as the call starts and appends the outcome (`L1-4 (done)`, `(exit code 0)`, `(session 3)`) when the result lands, so a blocking tool stays visible while it runs; namespaced MCP tools share one generic line (`* MCP <server>:<tool> (done)`). Plugin tools and custom tool calls keep the `[tool] …` / `[tool ok] …` whole-line style. Interactive TTY only (`interactive_terminal()`): piped/plain output and `--verbose` keep whole lines. A second call before the first result (parallel batch), or a prompt box printed while the tool runs, *ends* the open prefix as its own line and falls back to whole lines for the rest of the batch — the cursor is never moved, so a prefix wider than the terminal cannot be half-erased.
 - **`plyngent providers`**, **`config path|edit`**. Config open: `$VISUAL`/`$EDITOR` (wait), else system default (`xdg-open` / `open` / `startfile`, non-blocking). `/edit` stays blocking-only. No providers → optional edit then reload when waited.
 - Tools default on; workspace defaults to cwd; `--max-rounds` default 32. Readline history under platformdirs (`repl_history`). PTY: `close_all` on chat exit.