fix: parse space-separated allowed-tools strings (fixes #327)

src/skillspector/nodes/analyzers/mcp_least_privilege.py

@@ -246,16 +246,20 @@ def _normalize_allowed_tools(
 ) -> list[str]:
     """Coerce a manifest ``allowed-tools`` value into a list of tool names.
 
-    Accepts the list form (``[Bash, Read]``) and the comma-separated string
-    form (``"Bash, Read"``). Anything else yields an empty list.
+    Accepts the list form (``[Bash, Read]``), the comma-separated string
+    form (``"Bash, Read"``), and the space-separated string form
+    (``"Bash Read"``). Anything else yields an empty list.
     """
     tools: list[str] = []
     if isinstance(value, list):
         candidates = iter(value)
     elif isinstance(value, str):
-        # A bounded split prevents a comma-dense declaration from creating an
-        # arbitrarily large temporary list before the analyzer can stop it.
-        candidates = iter(value.split(",", _MAX_DECLARATION_VALUES))
+        if "," in value:
+            # A bounded split prevents a comma-dense declaration from creating an
+            # arbitrarily large temporary list before the analyzer can stop it.
+            candidates = iter(value.split(",", _MAX_DECLARATION_VALUES))
+        else:
+            candidates = iter(value.split(None, _MAX_DECLARATION_VALUES))
     else:
         return tools
 

src/skillspector/nodes/build_context.py

@@ -1458,22 +1458,28 @@ def _string_list(value: object) -> list[str]:
 
     manifest["triggers"] = _string_list(data.get("triggers", []))
     manifest["permissions"] = _string_list(data.get("permissions", []))
+    # `allowed-tools` (Agent Skills standard) — accept list, comma string, or space-separated string.
     allowed_tools = data.get("allowed-tools", [])
     if isinstance(allowed_tools, str):
-        tools: list[str] = []
-        cursor = 0
-        while cursor <= len(allowed_tools):
-            _check()
-            separator = allowed_tools.find(",", cursor)
-            if separator < 0:
-                separator = len(allowed_tools)
-            item = allowed_tools[cursor:separator].strip()
-            if item:
-                tools.append(_scalar_text(item))
-            if separator == len(allowed_tools):
-                break
-            cursor = separator + 1
-        manifest["allowed-tools"] = tools
+        if "," in allowed_tools:
+            tools: list[str] = []
+            cursor = 0
+            while cursor <= len(allowed_tools):
+                _check()
+                separator = allowed_tools.find(",", cursor)
+                if separator < 0:
+                    separator = len(allowed_tools)
+                item = allowed_tools[cursor:separator].strip()
+                if item:
+                    tools.append(_scalar_text(item))
+                if separator == len(allowed_tools):
+                    break
+                cursor = separator + 1
+            manifest["allowed-tools"] = tools
+        else:
+            manifest["allowed-tools"] = [
+                _scalar_text(t) for t in allowed_tools.split() if t.strip()
+            ]
     elif isinstance(allowed_tools, list):
         manifest["allowed-tools"] = [
             item.strip() for item in _string_list(allowed_tools) if item.strip()

tests/nodes/test_build_context.py

@@ -892,6 +892,39 @@ def test_build_context_parses_allowed_tools_comma_string(tmp_path: Path) -> None
     assert result["manifest"]["allowed-tools"] == ["Bash", "Read"]
 
 
+def test_build_context_parses_allowed_tools_space_string(tmp_path: Path) -> None:
+    """`allowed-tools` space-separated string form is normalized to a list."""
+    (tmp_path / "SKILL.md").write_text(
+        "---\nname: deployer\ndescription: deploys services\nallowed-tools: Bash Read\n---\n",
+        encoding="utf-8",
+    )
+    state: SkillspectorState = {"skill_path": str(tmp_path)}
+    result = build_context(state)
+    assert result["manifest"]["allowed-tools"] == ["Bash", "Read"]
+
+
+def test_build_context_parses_allowed_tools_mixed_whitespace(tmp_path: Path) -> None:
+    """`allowed-tools` string with mixed whitespace (multiple spaces) is normalized."""
+    (tmp_path / "SKILL.md").write_text(
+        "---\nname: deployer\ndescription: deploys services\nallowed-tools: Bash  Read   Write\n---\n",
+        encoding="utf-8",
+    )
+    state: SkillspectorState = {"skill_path": str(tmp_path)}
+    result = build_context(state)
+    assert result["manifest"]["allowed-tools"] == ["Bash", "Read", "Write"]
+
+
+def test_build_context_parses_allowed_tools_single_space_string(tmp_path: Path) -> None:
+    """`allowed-tools` single tool as space-separated string yields one item."""
+    (tmp_path / "SKILL.md").write_text(
+        "---\nname: deployer\ndescription: deploys services\nallowed-tools: Bash\n---\n",
+        encoding="utf-8",
+    )
+    state: SkillspectorState = {"skill_path": str(tmp_path)}
+    result = build_context(state)
+    assert result["manifest"]["allowed-tools"] == ["Bash"]
+
+
 def test_build_context_reports_exclusion_boundary_without_descendants(tmp_path: Path) -> None:
     """Excluded directory trees produce one boundary record, not child records."""
     (tmp_path / "SKILL.md").write_text("# Skill\n", encoding="utf-8")

tests/test_mcp_least_privilege.py

@@ -286,6 +286,18 @@ def test_allowed_tools_comma_string_no_lp3(self):
             f"allowed-tools should satisfy LP3, got: {[f.rule_id for f in findings]}"
         )
 
+    def test_allowed_tools_space_string_no_lp3(self):
+        """allowed-tools space-string form ('Bash Read') is also a declaration → no LP3."""
+        state = _make_state("mcp_underdeclared_skill")
+        state["manifest"]["permissions"] = None
+        state["manifest"]["allowed-tools"] = "Bash Read"
+        result = mcp_least_privilege.node(state)
+        findings = result["findings"]
+        lp3_findings = [f for f in findings if f.rule_id == "LP3"]
+        assert lp3_findings == [], (
+            f"allowed-tools should satisfy LP3, got: {[f.rule_id for f in findings]}"
+        )
+
     def test_allowed_tools_underdeclared_fires_lp1(self):
         """allowed-tools: [Read] + Bash code → LP3 suppressed but LP1 fires HIGH for shell."""
         state = _make_state("mcp_underdeclared_skill")