v0.2.0 to v0.3.0

---

name: daemon-backend-cursor

description: >

Nested daemon-cli-backends reference for the Cursor daemon backend's flag

surface. Read this only when a daemon task needs Cursor-specific CLI flags

(model selection, output/tooling switches): it routes you to the installed

CLI's live help via shell and shows how to translate that help into the

generic `backend_options` mechanism. It is not a flag catalog.

related_files:

- src/lingtai/tools/daemon/manual/reference/cli-backends/SKILL.md

maintenance: |

Tracks the Cursor daemon backend flag-discovery topic it documents; update when that integration changes.

---

# Cursor Daemon Backend — Flag Discovery Entrypoint

The installed CLI's own help is the authority for Cursor Agent flags; this page

is only the entrypoint. Conversion rules live in the parent

[`reference/cli-backends/SKILL.md`](../../../SKILL.md).

## Discover flags from the installed CLI

so root help is authoritative (keychain errors happen before help on some builds).

conversion rules (nothing Cursor-specific is added).

## Example: model selection via the generic route

`backend_options` keys become long flags, inserted after the harness-owned

flags and before the task prompt:

```jsonc

{

"backend": "cursor",

"tasks": [{

"task": "Implement and validate the change.",

"tools": [],

"backend_options": {

"model": "opus"

}

}]

}

// argv: --model opus

```

The flag and model vocabulary belong to the installed CLI — LingTai does

not validate, enumerate, or simulate them. Confirm `--model` and its

accepted values in your installed `agent --help` before relying on this; an

unknown flag or value is the CLI's error, not the daemon's.

## Source-pinned stream-json usage

For installed `agent-cli@2026.05.28-a70ca7c`, accept usage only from `type=result`, `subtype=success`, `is_error=false` with all four non-negative integer fields: `inputTokens`, `outputTokens`, `cacheReadTokens`, `cacheWriteTokens`.

`inputTokens` is already net; UI-only `cli_tokens` adds read + write as cached, preserves raw usage, ignores invalid/all-zero blocks, and counts duplicate terminal results once.

Join model only from a preceding matching `system/init` by `session_id`; provider stays unknown because this source emits no provider identity (do not infer it from `apiKeySource`, model, backend, credentials, or environment). This is version-pinned, not a cross-release claim.

## Subscription & auth

Cursor account/subscription (keychain login); LingTai does not inject

credentials — the CLI must be signed in.

Official docs: https://docs.cursor.com/agent

## Harness boundary

Cursor declares no reserved-flag list at validation, so nothing is refused

beyond generic key/value safety rules. Still, do not re-set harness-owned

surfaces: `-p` (non-interactive

print mode), `--force` (allows file modifications in print mode),

`--output-format stream-json` (one JSON event per stdout line — the daemon's

progress/result parser and the session-id capture depend on it), and

`--resume` (owned by `ask` follow-ups, which replay the captured session id).

Session and completion: the first session-id-shaped stream event is stored

as `cursor_session_id`; `ask` resumes with

`agent -p --force --resume <cursor_session_id> --output-format stream-json

<message>` (one follow-up in flight per session). Per-run MCP injection is

not wired for this backend yet, so no `finish` contract: success comes from

the stream's final result event and the process exit code.

`backend_options` is honored only at `emanate` time; `ask` follow-ups reuse the

session without re-passing it.