(MOT-4526) feat(cursor): add login-backed provider and agent worker

README.md

@@ -46,6 +46,7 @@ npx skills add iii-hq/iii --all
 | [`grok`](grok/) | Rust | xAI Grok CLI as an iii worker — `grok::*` spawn the grok CLI for headless turns (`grok --print --output-format streaming-json`), mirror raw events onto `grok::events`, and stream AgentEvent frames onto `agent::events`. |
 | [`devin`](devin/) | Rust | Devin as an iii worker: `devin::run` drives the local devin CLI and streams AgentEvent frames onto `agent::events`, `devin::session::*` wrap the Devin cloud session lifecycle, and `devin::api` reaches any v3 endpoint. |
 | [`claude-code`](claude-code/) | Node | Claude Code as an iii worker — `claude::*` runs headless Claude Code turns, mirrors raw messages onto `claude::events`, and streams AgentEvent frames onto `agent::events`. |
+| [`cursor`](cursor/) | Node | Cursor through normal Cursor CLI login as a text-only LLM Router provider plus a coding-agent worker for local ACP turns, with the optional `sdk.v1` Bridge for cloud/API-key agent sessions. |
 | [`pi`](pi/) | Node | Pi coding agent as an iii worker — `pi::*` run headless Pi turns, mirror raw events onto `pi::events`, and stream AgentEvent frames onto `agent::events`. |
 | [`hermes`](hermes/) | Python | Hermes agent as an iii worker — `hermes::run` runs headless turns with the iii runtime context, `hermes::send` delivers to 27+ messaging platforms, and inbound platform/webhook events republish via `hermes::inbound`. |
 | [`opencode`](opencode/) | Node | OpenCode as an iii worker — `opencode::*` run headless OpenCode turns via `opencode run --format json`, mirror raw JSON events onto `opencode::events`, and stream AgentEvent frames (with usage + cost) onto `agent::events`. |

acp/Cargo.toml

@@ -2,7 +2,7 @@
 
 [package]
 name = "iii-acp"
-version = "0.2.2"
+version = "0.3.0"
 edition = "2024"
 description = "Agent Client Protocol worker for iii-engine"
 license = "Apache-2.0"

acp/README.md

@@ -8,7 +8,7 @@ Editors and clients that already speak ACP launch `iii-acp` as a subprocess
 and drive it through their native agent UI. No editor plugin, no fork, no
 bespoke per-client integration.
 
-> Status: 0.1.0. Server-side only (`acp-client` for consuming external ACP
+> Status: 0.3.0. Server-side only (`acp-client` for consuming external ACP
 > agents ships separately). All eleven client→agent methods are implemented
 > (`initialize`, `authenticate`, `session/{new,load,resume,list,prompt,cancel,close,set_mode,set_config_option}`)
 > plus the `session/update` agent→client notification. Reverse-RPC paths
@@ -17,6 +17,10 @@ bespoke per-client integration.
 > internal iii brains use iii primitives directly for filesystem and
 > terminal access. Full per-method status in the [Methods](#methods) table.
 
+## Upgrading from 0.2
+
+Version 0.3 stores records, history, ownership, and prompt claims in the isolated `acp-v0.3` state scope. Existing 0.2 sessions remain untouched but are not listed or loadable through 0.3. This deliberate compatibility fence prevents mixed 0.2 and 0.3 processes from mutating the same history or dispatching overlapping prompts; finish or close important 0.2 sessions before upgrading.
+
 ## Why this exists (vs MCP, skills, agent workers)
 
 These are stack-able layers, not alternatives. ACP fills the slot that the
@@ -147,6 +151,7 @@ iii-acp --use-canonical-brain --model claude-sonnet-4-5-20250929 --provider anth
 | `--engine-url` (`-e`, `IIIACP_ENGINE_URL`) | iii engine WebSocket URL. Default `ws://localhost:49134`. |
 | `--debug` (`-d`) | Verbose tracing on stderr. |
 | `--brain-fn` (`IIIACP_BRAIN_FN`) | iii function id that runs the prompt turn. Falls back to a built-in echo brain when unset. Canonical value is `run::start_and_wait` (turn-orchestrator). |
+| `--brain-stop-fn` (`IIIACP_BRAIN_STOP_FN`) | Optional iii function id called with `session_id` when ACP cancels an external brain turn. |
 | `--use-canonical-brain` (`IIIACP_USE_CANONICAL_BRAIN`) | Shortcut for `--brain-fn run::start_and_wait`. |
 | `--model` (`IIIACP_MODEL`) | Model id forwarded to the brain (e.g. `claude-sonnet-4-5-20250929`). |
 | `--provider` (`IIIACP_PROVIDER`) | Provider id forwarded to the brain (e.g. `anthropic`). Routes to `provider::<provider>::complete`. |
@@ -291,17 +296,17 @@ already subscribe to. **No bespoke iii-acp publish protocol.**
 
 ## State layout
 
-All keys live in scope `acp`. `connId` is regenerated per subprocess so
-concurrent editors don't collide.
+All keys live in scope `acp-v0.3`. Session IDs are global UUIDs, while
+`conn_id` is stored as ownership metadata and regenerated per subprocess.
 
-```
-<connId>:sessions:_index           = ["sess_a", "sess_b", ...]
-<connId>:sessions:<sessId>         = { sessionId, connId, cwd, mcpServers, created_at_ms, last_activity_ms }
-<connId>:sessions:<sessId>:history = [ session/update entries ... ]
+```text
+sessions:_index            = ["sess_a", "sess_b", ...]
+sessions:<session_id>      = { session_id, conn_id, cwd, mcp_servers, created_at_ms, last_activity_ms, mode, config_options }
+sessions:<session_id>:history = { entries, cursor_item_ids, owner_conn_id, active_prompt, closed, closed_by_conn_id }
 ```
 
 Streaming wire: `agent::events` (per-session events), per-connection topic
-`acp:<connId>:session:<sessId>:cancel` (best-effort cancel signal).
+`acp:<conn_id>:session:<session_id>:cancel` (best-effort cancel signal).
 
 ## Wire example (raw stdio)
 
@@ -318,5 +323,5 @@ Replies stream on stdout, one JSON frame per line.
 cargo test
 ```
 
-17 lib + 7 protocol envelope tests. Integration smoke against a live engine
+37 lib + 10 protocol envelope tests. Integration smoke against a live engine
 lives in the iii test harness.