claude: run /analyze in a forked subagent

src/specify_cli/integrations/claude/__init__.py

@@ -34,6 +34,15 @@
     "taskstoissues": "Optional filter or label for GitHub issues",
 }
 
+# Per-command frontmatter overrides for skills that should run in a forked
+# subagent context. Read-only analysis commands are good candidates: the
+# heavy reads (spec/plan/tasks artefacts) collapse to a short summary,
+# so isolating them keeps the main conversation context clean.
+# See https://code.claude.com/docs/en/skills#run-skills-in-a-subagent
+FORK_CONTEXT_COMMANDS: dict[str, dict[str, str]] = {
+    "analyze": {"context": "fork", "agent": "general-purpose"},
+}
+
 
 class ClaudeIntegration(SkillsIntegration):
     """Integration for Claude Code skills."""
@@ -232,6 +241,11 @@ def setup(
             if hint:
                 updated = self.inject_argument_hint(updated, hint)
 
+            fork_config = FORK_CONTEXT_COMMANDS.get(stem)
+            if fork_config:
+                for key, value in fork_config.items():
+                    updated = self._inject_frontmatter_flag(updated, key, value)
+
             if updated != content:
                 path.write_bytes(updated.encode("utf-8"))
                 self.record_file_in_manifest(path, project_root, manifest)

tests/integrations/test_integration_claude.py

@@ -9,7 +9,7 @@
 
 from specify_cli.integrations import INTEGRATION_REGISTRY, get_integration
 from specify_cli.integrations.base import IntegrationBase
-from specify_cli.integrations.claude import ARGUMENT_HINTS
+from specify_cli.integrations.claude import ARGUMENT_HINTS, FORK_CONTEXT_COMMANDS
 from specify_cli.integrations.manifest import IntegrationManifest
 
 
@@ -496,6 +496,72 @@ def test_non_claude_post_process_is_identity(self, tmp_path):
         assert codex.post_process_skill_content(content) == content
 
 
+class TestClaudeForkContext:
+    """Verify context: fork is injected only for commands listed in FORK_CONTEXT_COMMANDS."""
+
+    def test_analyze_skill_runs_in_forked_subagent(self, tmp_path):
+        """speckit-analyze must opt into context: fork + agent."""
+        i = get_integration("claude")
+        m = IntegrationManifest("claude", tmp_path)
+        i.setup(tmp_path, m, script_type="sh")
+        analyze_skill = tmp_path / ".claude/skills/speckit-analyze/SKILL.md"
+        assert analyze_skill.exists()
+        content = analyze_skill.read_text(encoding="utf-8")
+        parts = content.split("---", 2)
+        parsed = yaml.safe_load(parts[1])
+        assert parsed.get("context") == "fork"
+        assert parsed.get("agent") == "general-purpose"
+
+    def test_other_skills_do_not_fork(self, tmp_path):
+        """Skills not in FORK_CONTEXT_COMMANDS must not get context: fork."""
+        i = get_integration("claude")
+        m = IntegrationManifest("claude", tmp_path)
+        created = i.setup(tmp_path, m, script_type="sh")
+        skill_files = [f for f in created if f.name == "SKILL.md"]
+        for f in skill_files:
+            stem = f.parent.name
+            if stem.startswith("speckit-"):
+                stem = stem[len("speckit-"):]
+            if stem in FORK_CONTEXT_COMMANDS:
+                continue
+            content = f.read_text(encoding="utf-8")
+            parts = content.split("---", 2)
+            parsed = yaml.safe_load(parts[1])
+            assert "context" not in parsed, (
+                f"{f.parent.name}: must not have context frontmatter"
+            )
+            assert "agent" not in parsed, (
+                f"{f.parent.name}: must not have agent frontmatter"
+            )
+
+    def test_fork_flags_inside_frontmatter(self, tmp_path):
+        """context/agent must appear in the frontmatter, not in the body."""
+        i = get_integration("claude")
+        m = IntegrationManifest("claude", tmp_path)
+        i.setup(tmp_path, m, script_type="sh")
+        analyze_skill = tmp_path / ".claude/skills/speckit-analyze/SKILL.md"
+        content = analyze_skill.read_text(encoding="utf-8")
+        parts = content.split("---", 2)
+        assert len(parts) >= 3
+        frontmatter = parts[1]
+        body = parts[2]
+        assert "context: fork" in frontmatter
+        assert "agent: general-purpose" in frontmatter
+        assert "context: fork" not in body
+        assert "agent: general-purpose" not in body
+
+    def test_fork_injection_idempotent(self, tmp_path):
+        """Re-running setup must not duplicate the fork frontmatter keys."""
+        i = get_integration("claude")
+        m = IntegrationManifest("claude", tmp_path)
+        i.setup(tmp_path, m, script_type="sh")
+        i.setup(tmp_path, m, script_type="sh")
+        analyze_skill = tmp_path / ".claude/skills/speckit-analyze/SKILL.md"
+        content = analyze_skill.read_text(encoding="utf-8")
+        assert content.count("context: fork") == 1
+        assert content.count("agent: general-purpose") == 1
+
+
 class TestClaudeHookCommandNote:
     """Verify dot-to-hyphen normalization note is injected in hook sections."""