Add cursor agent preset for Auto vs static model comparison

CHANGES

@@ -1,5 +1,8 @@
 # Changelog
 
+## v1.5.0 — 2026-08-21
+- Add built-in `cursor` agent preset (`agent -p --force --trust`) using Cursor Auto when `--model` is omitted; document comparing Auto to other agents (claude/codex/etc.), optional `cursor-composer` example, and `CURSOR_API_KEY` auth (README, `config.example.yaml`, Docker Compose)
+
 ## v1.4.5 — 2026-05-22
 - Fix: commit missing `token_accum` parameter in `run_agent_loop` that caused a TypeError when tool-use models ran queries
 

README.md

@@ -27,7 +27,44 @@ uv pip install -e ".[dev]"
 
 ## Configuration
 
-Copy `config.example.yaml` to `agent-tester.yaml` (or `agent-tester.yml`) in your target repo to customize agents. Built-in presets are available for `claude`, `aider`, and `codex`.
+Copy `config.example.yaml` to `agent-tester.yaml` (or `agent-tester.yml`) in your target repo to customize agents. Built-in presets are available for `claude`, `aider`, `codex`, and `cursor`.
+
+### Comparing Cursor Auto to another agent
+
+The `cursor` preset runs the [Cursor CLI](https://cursor.com/docs/cli/overview) in print mode without `--model`, which uses **Auto** (the model router). Run it alongside any other agent (a static Claude/Codex/Aider setup, or another Cursor invocation with `--model`) in the same pass:
+
+```bash
+# Cursor Auto vs Claude
+agent-tester run "Refactor the auth module" --agents cursor,claude
+
+# Cursor Auto vs Codex
+agent-tester run "Refactor the auth module" --agents cursor,codex
+```
+
+You can also pin a Cursor model (or any other CLI agent) as a separate config entry — useful when you want two Cursor variants, or to show that any agent tool works the same way:
+
+```yaml
+agents:
+  cursor:
+    command: "agent -p --force --trust {prompt}"
+    commit_style: auto
+    timeout: 600
+    # Prefer exporting CURSOR_API_KEY in the shell / Docker env.
+    # Or set it here (do not commit secrets):
+    # env:
+    #   CURSOR_API_KEY: "..."
+
+  cursor-composer:
+    command: "agent -p --force --trust --model composer-2.5 {prompt}"
+    commit_style: auto
+    timeout: 600
+```
+
+```bash
+agent-tester run "Refactor the auth module" --agents cursor,cursor-composer
+```
+
+Do not pass Cursor's `-w`/`--worktree` flag — AgentTester already isolates each agent in its own git worktree. See [Cursor CLI authentication](#cursor-cli) for `CURSOR_API_KEY` / `agent login`.
 
 ### Config file discovery
 
@@ -108,6 +145,29 @@ your-repo/.agent-tester/skills/style.md   # adds a new skill for this project
 
 ## Authentication
 
+### Cursor CLI
+
+The `cursor` shell agent uses the Cursor CLI (`agent`), not the `providers:` block. Authenticate in one of these ways:
+
+1. **Interactive:** run `agent login` once on the host (stores credentials for later runs).
+2. **API key:** export `CURSOR_API_KEY` in the environment (recommended for CI / Docker / headless). AgentTester forwards the process environment to each agent; `docker-compose.yaml` also passes `CURSOR_API_KEY` through from the host.
+3. **Per-agent config:** set `env.CURSOR_API_KEY` on an agent entry in YAML (useful for remote hosts). Prefer the environment over committing secrets to config.
+
+```bash
+export CURSOR_API_KEY=your_api_key_here
+agent-tester run "…" --agents cursor,claude
+```
+
+```yaml
+agents:
+  cursor:
+    command: "agent -p --force --trust {prompt}"
+    env:
+      CURSOR_API_KEY: "your_api_key_here"   # prefer env / Docker; do not commit
+```
+
+### Providers (evaluators and REPL models)
+
 Define a `providers` block to share credentials across evaluators and REPL model agents. Each provider type reads credentials from a standard environment variable automatically — no `api_key_env` required unless you want to override the default.
 
 | `type` | Description | Default env var | Install |
@@ -337,7 +397,7 @@ The command walks through two phases — select sessions to delete entirely, the
 
 ## Docker
 
-Provider API keys are forwarded automatically from the host environment — set any of `ANTHROPIC_API_KEY`, `AZURE_OPENAI_API_KEY`, `GOOGLE_API_KEY`, `BEDROCK_API_KEY`, or the standard `AWS_*` variables before running.
+Provider and agent API keys are forwarded automatically from the host environment — set any of `CURSOR_API_KEY`, `ANTHROPIC_API_KEY`, `AZURE_OPENAI_API_KEY`, `GOOGLE_API_KEY`, `BEDROCK_API_KEY`, or the standard `AWS_*` variables before running.
 
 ```bash
 # Open REPL against the current directory

config.example.yaml

@@ -1,6 +1,6 @@
 # AgentTester configuration
 # Copy to agent-tester.yaml in your target repo.
-# Entries here override built-in presets (claude, aider, codex).
+# Entries here override built-in presets (claude, aider, codex, cursor).
 #
 # host: "localhost" (default) runs locally; set to "user@server" for SSH.
 
@@ -23,6 +23,33 @@ agents:
     commit_style: auto
     timeout: 600
 
+  # Cursor CLI (install: https://cursor.com/docs/cli/overview).
+  # Omitting --model uses Auto (the model router). Compare against any
+  # other agent, e.g.:
+  #   agent-tester run "…" --agents cursor,claude
+  # Auth: export CURSOR_API_KEY, or `agent login`, or set env below.
+  # Do not pass Cursor's -w/--worktree — AgentTester already isolates
+  # each agent in its own worktree.
+  cursor:
+    command: "agent -p --force --trust {prompt}"
+    host: localhost
+    commit_style: auto
+    timeout: 600
+    # env:
+    #   CURSOR_API_KEY: "..."   # prefer exporting in the shell / Docker
+
+  # Optional: pin a Cursor model (same CLI, static --model). Shows that
+  # any agent tool can be added the same way — not required for Auto vs
+  # Claude/Codex comparisons.
+  #   agent-tester run "…" --agents cursor,cursor-composer
+  # cursor-composer:
+  #   command: "agent -p --force --trust --model composer-2.5 {prompt}"
+  #   host: localhost
+  #   commit_style: auto
+  #   timeout: 600
+  #   env:
+  #     CURSOR_API_KEY: "..."
+
   # Example: agent running on a remote GPU box
   # remote-claude:
   #   command: 'claude -p {prompt} --allowedTools "Bash,Read,Edit"'

docker-compose.yaml

@@ -10,6 +10,7 @@ services:
     environment:
       - SSH_AUTH_SOCK=/ssh-agent
       # Pass API keys through to agents
+      - CURSOR_API_KEY
       - ANTHROPIC_API_KEY
       - OPENAI_API_KEY
       # Azure AI Foundry / Azure OpenAI

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "agenttester"
-version = "1.4.5"
+version = "1.5.0"
 description = "Run a prompt against multiple coding agents in parallel and compare results"
 readme = "README.md"
 requires-python = ">=3.10"

src/agenttester/cli.py

@@ -457,7 +457,7 @@ def list_agents(
     all_agents = load_config(config)
     console.print("[bold]Available agents:[/bold]\n")
     for name, agent in sorted(all_agents.items()):
-        preset_names = ("claude", "aider", "codex")
+        preset_names = ("claude", "aider", "codex", "cursor")
         tag = "[dim](preset)[/dim]" if name in preset_names else ""
         console.print(f"  [bold]{name}[/bold] {tag}")
         console.print(f"    command: [dim]{agent.command}[/dim]")

src/agenttester/presets.py

@@ -22,4 +22,14 @@
         "commit_style": "auto",
         "timeout": 600,
     },
+    # Uses Cursor Auto (model router) when --model is omitted.
+    # Compare against any other agent (claude, codex, …) or a second
+    # Cursor entry with --model <id> (see `agent models`). Auth via
+    # CURSOR_API_KEY or `agent login`. Do not pass Cursor's -w/--worktree —
+    # AgentTester already isolates worktrees.
+    "cursor": {
+        "command": "agent -p --force --trust {prompt}",
+        "commit_style": "auto",
+        "timeout": 600,
+    },
 }

tests/test_cli.py

@@ -45,6 +45,7 @@ def test_lists_presets(self) -> None:
         assert "claude" in result.output
         assert "aider" in result.output
         assert "codex" in result.output
+        assert "cursor" in result.output
 
 
 class TestRunValidation:

tests/test_config.py

@@ -47,6 +47,7 @@ def test_includes_builtin_presets(self) -> None:
         assert "claude" in agents
         assert "aider" in agents
         assert "codex" in agents
+        assert "cursor" in agents
 
     def test_preset_types(self) -> None:
         agents = load_config()
@@ -61,6 +62,14 @@ def test_aider_preset_has_manual_commit(self) -> None:
         agents = load_config()
         assert agents["aider"].commit_style == "manual"
 
+    def test_cursor_preset_uses_auto_router(self) -> None:
+        agents = load_config()
+        assert agents["cursor"].commit_style == "auto"
+        assert "--model" not in agents["cursor"].command
+        assert "agent -p" in agents["cursor"].command
+        assert "--force" in agents["cursor"].command
+        assert "--trust" in agents["cursor"].command
+
     def test_presets_default_to_localhost(self) -> None:
         agents = load_config()
         for agent in agents.values():
@@ -125,11 +134,11 @@ def test_yaml_with_env(self, tmp_path: Path) -> None:
     def test_missing_config_file_returns_presets(self) -> None:
         agents = load_config(Path("/nonexistent/config.yaml"))
         assert "claude" in agents
-        assert len(agents) == 3  # only presets
+        assert len(agents) == 4  # only presets
 
     def test_none_config_returns_presets(self) -> None:
         agents = load_config(None)
-        assert len(agents) >= 3
+        assert len(agents) >= 4
 
     def test_loads_agent_tester_filename(self, tmp_path: Path) -> None:
         config_file = tmp_path / "agent-tester.yaml"