detect: exclude fixture dirs by default

docs/agent-recipes.md

@@ -67,6 +67,11 @@ agents-shipgate apply-patches \
 
 Consume the response to decide whether to proceed. Key fields:
 
+- Detection silently skips common fixture corpus directories such as
+  `fixtures/`, `_fixtures/`, `__fixtures__/`, `testdata/`, `test_data/`,
+  `test-fixtures/`, `test_fixtures/`, `golden/`, and `goldens/` when they
+  are below the selected workspace. Point `--workspace` directly at a
+  fixture project if you intentionally want to classify that fixture itself.
 - `is_agent_project` — `true` when at least one Python framework
   scored ≥ 2.0 with a strong signal.
 - `frameworks[]` — per-framework scores + evidence + candidate file

docs/zero-install.md

@@ -31,12 +31,14 @@ The script's output is a **structural subset** of `agents-shipgate detect --json
   "codex_plugin_candidates": [{"mode": "package", "path": "..."}],
   "next_action": "agents-shipgate init --workspace .",
   "workspace_signals": {...},
-  "script_version": "0.2.0"
+  "script_version": "0.2.1"
 }
 ```
 
 Like the canonical CLI, the script parse-probes each glob-matched MCP/OpenAPI candidate before suggesting it — a filename match is not a guarantee. A Cursor plugin `mcp.json` is an `mcpServers`-style host config, not an MCP tools-array export; suggesting it would make the next `init --write` → `scan` step fail. Rejected candidates appear under `excluded_sources` (`{type, path, reason}`) instead of `suggested_sources`. The probe is **JSON-only** (stdlib has no YAML parser): a `.json` candidate the adapters would reject is excluded here too, while a `.yaml`/`.yml` OpenAPI spec is always kept as a suggestion (never wrongly dropped). The real-world miss this guards against — `mcpServers`-style host configs — is always JSON, so the probe is exact where it matters.
 
+Like `agents-shipgate detect`, the script silently skips common fixture corpus directories such as `fixtures/`, `_fixtures/`, `__fixtures__/`, `testdata/`, `test_data/`, `test-fixtures/`, `test_fixtures/`, `golden/`, and `goldens/` when they are below the selected workspace. Point `--workspace` directly at a fixture project if you intentionally want to classify that fixture itself.
+
 The script and the canonical CLI are pinned to **structural verdict parity** by [`tests/test_zero_install_detector.py`](https://github.com/ThreeMoonsLab/agents-shipgate/blob/main/tests/test_zero_install_detector.py): same `is_agent_project`, same fired frameworks, same suggested sources, same excluded sources, and same Codex plugin candidates for every sample in `samples/`. Field-by-field byte parity is not pinned and not promised — the script is not a drop-in replacement for the CLI.
 
 **When to use this:** you're a coding agent (Claude Code, Codex, Cursor) deciding *whether* to propose Shipgate. The script tells you in one fetch + one Python invocation. The full flow (`init`, `scan`, `apply-patches`) requires the actual install.

llms-full.txt

@@ -717,6 +717,11 @@ agents-shipgate apply-patches \
 
 Consume the response to decide whether to proceed. Key fields:
 
+- Detection silently skips common fixture corpus directories such as
+  `fixtures/`, `_fixtures/`, `__fixtures__/`, `testdata/`, `test_data/`,
+  `test-fixtures/`, `test_fixtures/`, `golden/`, and `goldens/` when they
+  are below the selected workspace. Point `--workspace` directly at a
+  fixture project if you intentionally want to classify that fixture itself.
 - `is_agent_project` — `true` when at least one Python framework
   scored ≥ 2.0 with a strong signal.
 - `frameworks[]` — per-framework scores + evidence + candidate file

src/agents_shipgate/cli/discovery/artifacts.py

@@ -88,8 +88,17 @@
     "build",
     "dist",
     "env",
+    "fixtures",
+    "_fixtures",
+    "__fixtures__",
+    "golden",
+    "goldens",
     "node_modules",
     "target",
+    "test-fixtures",
+    "test_fixtures",
+    "test_data",
+    "testdata",
     "venv",
 }
 SKIP_DIR_PREFIXES = (".venv",)

tests/test_adapter_static_only.py

@@ -193,7 +193,7 @@ class AllowedException:
     AllowedException(
         relative_path="cli/discovery/artifacts.py",
         surface="attr_call:subprocess.run",
-        line=430,
+        line=439,
         snippet=(
             "subprocess.run(['git', '-C', str(workspace), 'rev-parse', "
             "'--show-toplevel'], check=False, capture_output=True, "
@@ -208,7 +208,7 @@ class AllowedException:
     AllowedException(
         relative_path="cli/discovery/artifacts.py",
         surface="attr_call:subprocess.run",
-        line=446,
+        line=455,
         snippet=(
             "subprocess.run(['git', '-C', str(workspace), 'ls-files', "
             "'-co', '--exclude-standard', '--full-name', '-z', '--', "
@@ -1283,7 +1283,7 @@ def test_allowed_exceptions_pin_subprocess_run_per_call_site() -> None:
     ``subprocess.run`` AllowedException entries (one per call site at
     lines 480, 481, 486), not one blanket entry that permits all
     occurrences. Same for ``cli/discovery/artifacts.py`` (two call
-    sites at 361 and 377). Adding a fourth ``subprocess.run`` to
+    sites at 439 and 455). Adding a fourth ``subprocess.run`` to
     ``triggers.py`` must require adding a new ALLOWED_EXCEPTIONS entry.
 
     If the test fails because lines drifted, that is the intended
@@ -1312,7 +1312,7 @@ def test_allowed_exceptions_pin_subprocess_run_per_call_site() -> None:
     assert len(artifacts_subprocess_run) == 2, (
         f"Expected 2 distinct AllowedException entries for "
         f"cli/discovery/artifacts.py subprocess.run calls (one per "
-        f"call site at lines 361 and 377), got "
+        f"call site at lines 439 and 455), got "
         f"{len(artifacts_subprocess_run)}."
     )
     verify_subprocess_run = by_file_surface.get(

tests/test_detect.py

@@ -13,6 +13,41 @@
 from agents_shipgate.schemas.detect import DetectResult
 
 SAMPLES = Path(__file__).resolve().parent.parent / "samples"
+FIXTURE_SKIP_DIR_NAMES = (
+    "fixtures",
+    "_fixtures",
+    "__fixtures__",
+    "testdata",
+    "test_data",
+    "test-fixtures",
+    "test_fixtures",
+    "golden",
+    "goldens",
+)
+
+
+def _write_skipped_fixture_signals(root: Path) -> None:
+    root.mkdir(parents=True, exist_ok=True)
+    (root / "agent.py").write_text(
+        "from langchain.tools import tool\n\n@tool\ndef lookup():\n    return 'x'\n",
+        encoding="utf-8",
+    )
+    tools = root / "tools"
+    tools.mkdir()
+    (tools / "payments-mcp.json").write_text(
+        '{"tools": [{"name": "create_payment_link", "description": "Create link."}]}',
+        encoding="utf-8",
+    )
+    (root / "broken-mcp.json").write_text("{not json", encoding="utf-8")
+    specs = root / "specs"
+    specs.mkdir()
+    (specs / "support.openapi.yaml").write_text(
+        "openapi: 3.1.0\ninfo:\n  title: T\n  version: '1'\npaths: {}\n",
+        encoding="utf-8",
+    )
+    plugin = root / "plugin" / ".codex-plugin"
+    plugin.mkdir(parents=True)
+    (plugin / "plugin.json").write_text("{}", encoding="utf-8")
 
 
 def test_detects_langchain_sample() -> None:
@@ -153,6 +188,21 @@ def test_detect_ignores_local_private_and_virtualenv_fixtures(tmp_path: Path) ->
     assert result.suggested_sources == []
 
 
+def test_detect_excludes_common_fixture_dirs_by_default(tmp_path: Path) -> None:
+    """Fixture corpora should not make an otherwise empty workspace look agentic."""
+    for dirname in FIXTURE_SKIP_DIR_NAMES:
+        _write_skipped_fixture_signals(tmp_path / dirname)
+
+    result = detect_workspace(tmp_path)
+
+    assert result.is_agent_project is False
+    assert result.frameworks == []
+    assert result.suggested_sources == []
+    assert result.excluded_sources == []
+    assert result.codex_plugin_candidates == []
+    assert result.workspace_signals.python_file_count == 0
+
+
 def test_detect_does_not_skip_workspace_because_parent_is_skipped_name(
     tmp_path: Path,
 ) -> None:
@@ -170,6 +220,22 @@ def test_detect_does_not_skip_workspace_because_parent_is_skipped_name(
     assert langchain.candidate_files == ["agent.py"]
 
 
+def test_detect_does_not_skip_workspace_named_fixtures(tmp_path: Path) -> None:
+    workspace = tmp_path / "fixtures"
+    workspace.mkdir()
+    (workspace / "agent.py").write_text(
+        "from langchain.tools import tool\n\n@tool\ndef lookup():\n    return 'x'\n",
+        encoding="utf-8",
+    )
+
+    result = detect_workspace(workspace)
+
+    assert result.is_agent_project is True
+    langchain = next(fw for fw in result.frameworks if fw.type == "langchain")
+    assert langchain.candidate_files == ["agent.py"]
+    assert result.workspace_signals.python_file_count == 1
+
+
 def test_detect_respects_gitignored_nested_agent_artifacts(tmp_path: Path) -> None:
     if not shutil.which("git"):
         pytest.skip("git is required for git-aware discovery regression coverage")
@@ -199,6 +265,25 @@ def test_detect_respects_gitignored_nested_agent_artifacts(tmp_path: Path) -> No
     assert result.suggested_sources == []
 
 
+def test_detect_excludes_common_fixture_dirs_with_git_candidates(
+    tmp_path: Path,
+) -> None:
+    if not shutil.which("git"):
+        pytest.skip("git is required for git-aware discovery regression coverage")
+
+    subprocess.run(["git", "init", "-q"], cwd=tmp_path, check=True)
+    _write_skipped_fixture_signals(tmp_path / "fixtures")
+
+    result = detect_workspace(tmp_path)
+
+    assert result.is_agent_project is False
+    assert result.frameworks == []
+    assert result.suggested_sources == []
+    assert result.excluded_sources == []
+    assert result.codex_plugin_candidates == []
+    assert result.workspace_signals.python_file_count == 0
+
+
 def test_pyproject_seeds_project_name_not_agent_name(tmp_path: Path) -> None:
     """pyproject [project].name → project_name_candidates, NOT
     agent_name_candidates (post-review correction)."""

tests/test_zero_install_detector.py

@@ -134,6 +134,24 @@ def test_script_emits_canonical_top_level_keys(script_module):
 SCRIPT_PARITY_GAPS: frozenset[str] = frozenset({"n8n_workflow_agent"})
 
 
+def _write_skipped_fixture_signals(root: Path) -> None:
+    root.mkdir(parents=True, exist_ok=True)
+    (root / "agent.py").write_text(
+        "from langchain.tools import tool\n\n@tool\ndef lookup():\n    return 'x'\n",
+        encoding="utf-8",
+    )
+    tools = root / "tools"
+    tools.mkdir()
+    (tools / "payments-mcp.json").write_text(
+        '{"tools": [{"name": "create_payment_link", "description": "Create link."}]}',
+        encoding="utf-8",
+    )
+    (root / "broken-mcp.json").write_text("{not json", encoding="utf-8")
+    plugin = root / "plugin" / ".codex-plugin"
+    plugin.mkdir(parents=True)
+    (plugin / "plugin.json").write_text("{}", encoding="utf-8")
+
+
 @pytest.mark.parametrize("sample_dir", _sample_dirs(), ids=_sample_ids())
 def test_script_verdict_matches_cli(script_module, sample_dir):
     """Structural parity: for every sample, the zero-install script
@@ -226,6 +244,40 @@ def test_script_finds_at_least_one_python_file_when_cli_does(
         )
 
 
+def test_script_and_cli_skip_common_fixture_dirs(script_module, tmp_path):
+    _write_skipped_fixture_signals(tmp_path / "fixtures")
+
+    script_result = script_module.detect(tmp_path)
+    cli_result = detect_workspace(tmp_path.resolve()).model_dump(mode="json")
+
+    for result in (script_result, cli_result):
+        assert result["is_agent_project"] is False
+        assert result["frameworks"] == []
+        assert result["suggested_sources"] == []
+        assert result["excluded_sources"] == []
+        assert result["codex_plugin_candidates"] == []
+        assert result["workspace_signals"]["python_file_count"] == 0
+
+
+def test_script_detects_workspace_named_fixture_dir(script_module, tmp_path):
+    workspace = tmp_path / "fixtures"
+    workspace.mkdir()
+    (workspace / "agent.py").write_text(
+        "from langchain.tools import tool\n\n@tool\ndef lookup():\n    return 'x'\n",
+        encoding="utf-8",
+    )
+
+    script_result = script_module.detect(workspace)
+    cli_result = detect_workspace(workspace.resolve()).model_dump(mode="json")
+
+    assert script_result["is_agent_project"] is True
+    assert cli_result["is_agent_project"] is True
+    assert [fw["type"] for fw in script_result["frameworks"]] == ["langchain"]
+    assert [fw["type"] for fw in cli_result["frameworks"]] == ["langchain"]
+    assert script_result["workspace_signals"]["python_file_count"] == 1
+    assert cli_result["workspace_signals"]["python_file_count"] == 1
+
+
 def test_script_excludes_mcpservers_config_like_cli(script_module, tmp_path):
     """The load-bearing parse-probe case: a Cursor-style ``mcpServers``
     host config matches the ``*mcp*.json`` glob but is not a tools-array

tools/shipgate-detect.py

@@ -22,6 +22,11 @@
 every sample in ``samples/``, so the two cannot drift on the load-bearing
 fields.
 
+Both this script and the canonical CLI silently skip common fixture corpus
+directories (for example ``fixtures/``, ``testdata/``, and ``golden/``) when
+those directories are below the selected workspace. Point ``--workspace``
+directly at a fixture project to detect that fixture itself.
+
 Like the canonical CLI, glob-matched MCP/OpenAPI candidates are
 parse-probed before they are suggested: a filename is a glob match, not a
 guarantee. A Cursor plugin ``mcp.json`` is an ``mcpServers``-style host
@@ -59,7 +64,7 @@
 from pathlib import Path
 from typing import Any
 
-SCRIPT_VERSION = "0.2.0"
+SCRIPT_VERSION = "0.2.1"
 
 # Framework signal vocabulary (mirror of cli/discovery/signals.py).
 LANGCHAIN_IMPORTS = {
@@ -120,7 +125,8 @@
     ".nox", ".svn", ".mypy_cache", ".next", ".pnpm-store", ".pytest_cache",
     ".ruff_cache", ".turbo", ".tox", ".venv", "__pycache__",
     "agents-shipgate-reports", "build", "dist", "env", "node_modules",
-    "target", "venv",
+    "target", "venv", "fixtures", "_fixtures", "__fixtures__", "golden",
+    "goldens", "test-fixtures", "test_fixtures", "test_data", "testdata",
 }
 PYPROJECT_NAME_RE = re.compile(r'^\s*name\s*=\s*["\']([^"\']+)["\']', re.MULTILINE)
 REQ_TOKEN_RE = re.compile(r"^\s*([A-Za-z0-9_.\-]+)", re.MULTILINE)