Implemented the next missing parity slice around agent configurations.

tests/test_agent_registry.py

@@ -0,0 +1,75 @@
+from __future__ import annotations
+
+import os
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+from src.agent_registry import load_agent_registry, render_agent_detail, render_agents_report
+
+
+def _write_agent(path: Path, *, name: str, description: str, body: str, extra: str = '') -> None:
+    payload = (
+        '---\n'
+        f'name: {name}\n'
+        f'description: "{description}"\n'
+        f'{extra}'
+        '---\n\n'
+        f'{body}\n'
+    )
+    path.write_text(payload, encoding='utf-8')
+
+
+class AgentRegistryTests(unittest.TestCase):
+    def test_project_agent_overrides_built_in_agent(self) -> None:
+        with tempfile.TemporaryDirectory() as home_dir, tempfile.TemporaryDirectory() as tmp_dir:
+            workspace = Path(tmp_dir)
+            agents_dir = workspace / '.claude' / 'agents'
+            agents_dir.mkdir(parents=True)
+            _write_agent(
+                agents_dir / 'Explore.md',
+                name='Explore',
+                description='Project-specific explore agent.',
+                body='Search this repository carefully before answering.',
+                extra=(
+                    'tools: read_file, grep_search\n'
+                    'model: child-model\n'
+                    'initialPrompt: Begin with rg-style discovery.\n'
+                ),
+            )
+
+            with patch.dict(os.environ, {'HOME': home_dir}):
+                snapshot = load_agent_registry(workspace)
+
+            active = {agent.agent_type: agent for agent in snapshot.active_agents}
+            self.assertIn('Explore', active)
+            self.assertEqual(active['Explore'].source, 'projectSettings')
+            self.assertEqual(active['Explore'].model, 'child-model')
+            self.assertEqual(active['Explore'].tools, ('read_file', 'grep_search'))
+            self.assertEqual(active['Explore'].initial_prompt, 'Begin with rg-style discovery.')
+
+            report = render_agents_report(snapshot, cwd=workspace)
+            self.assertIn('Explore [projectSettings]', report)
+            self.assertIn('Shadowed Agents', report)
+
+            detail = render_agent_detail(snapshot, 'Explore')
+            self.assertIn('Project-specific explore agent.', detail)
+            self.assertIn('Begin with rg-style discovery.', detail)
+            self.assertIn('Search this repository carefully before answering.', detail)
+
+    def test_invalid_agent_file_is_reported(self) -> None:
+        with tempfile.TemporaryDirectory() as home_dir, tempfile.TemporaryDirectory() as tmp_dir:
+            workspace = Path(tmp_dir)
+            agents_dir = workspace / '.claude' / 'agents'
+            agents_dir.mkdir(parents=True)
+            (agents_dir / 'broken.md').write_text(
+                '---\nname: broken\n---\n',
+                encoding='utf-8',
+            )
+
+            with patch.dict(os.environ, {'HOME': home_dir}):
+                snapshot = load_agent_registry(workspace)
+
+            self.assertEqual(len(snapshot.failed_files), 1)
+            self.assertIn('missing a description', snapshot.failed_files[0].error)

tests/test_agent_runtime.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import json
+import os
 import tempfile
 import unittest
 from pathlib import Path
@@ -112,6 +113,37 @@ def make_recording_streaming_urlopen_side_effect(
 
 
 class AgentRuntimeTests(unittest.TestCase):
+    def test_custom_project_agent_is_resolved_for_child_agent_configuration(self) -> None:
+        with tempfile.TemporaryDirectory() as home_dir, tempfile.TemporaryDirectory() as tmp_dir:
+            workspace = Path(tmp_dir)
+            agents_dir = workspace / '.claude' / 'agents'
+            agents_dir.mkdir(parents=True)
+            (agents_dir / 'Explore.md').write_text(
+                (
+                    '---\n'
+                    'name: Explore\n'
+                    'description: "Project-specific explore agent."\n'
+                    'tools: read_file, grep_search\n'
+                    'model: child-model\n'
+                    'initialPrompt: Start with a repository scan.\n'
+                    '---\n\n'
+                    'Search the repository and report findings.\n'
+                ),
+                encoding='utf-8',
+            )
+            with patch.dict(os.environ, {'HOME': home_dir}):
+                agent = LocalCodingAgent(
+                    model_config=ModelConfig(model='parent-model'),
+                    runtime_config=AgentRuntimeConfig(cwd=workspace),
+                )
+                agent_def = agent._resolve_agent_definition({'subagent_type': 'Explore'})
+                child_model = agent._resolve_child_model_config({}, agent_def)
+                child_tools = agent._filter_tools_for_agent(agent_def)
+            self.assertEqual(agent_def.source, 'projectSettings')
+            self.assertEqual(agent_def.initial_prompt, 'Start with a repository scan.')
+            self.assertEqual(child_model.model, 'child-model')
+            self.assertEqual(sorted(child_tools), ['grep_search', 'read_file'])
+
     def test_openai_client_parses_tool_calls(self) -> None:
         responses = [
             {

tests/test_agent_slash_commands.py

@@ -4,6 +4,7 @@ import tempfile
 import unittest
 import json
 import sys
+import os
 from pathlib import Path
 from unittest.mock import patch
 
@@ -119,6 +120,35 @@ class AgentSlashCommandTests(unittest.TestCase):
         self.assertIn('Hard input limit', result.final_output)
         self.assertIn('Auto-compact buffer', result.final_output)
 
+    def test_agents_command_lists_and_shows_custom_agents(self) -> None:
+        with tempfile.TemporaryDirectory() as home_dir, tempfile.TemporaryDirectory() as tmp_dir:
+            workspace = Path(tmp_dir)
+            agents_dir = workspace / '.claude' / 'agents'
+            agents_dir.mkdir(parents=True)
+            (agents_dir / 'reviewer.md').write_text(
+                (
+                    '---\n'
+                    'name: reviewer\n'
+                    'description: "Review implementation changes carefully."\n'
+                    'tools: read_file, grep_search\n'
+                    'model: test-child-model\n'
+                    '---\n\n'
+                    'Inspect code changes and summarize risks.\n'
+                ),
+                encoding='utf-8',
+            )
+            with patch.dict(os.environ, {'HOME': home_dir}):
+                agent = LocalCodingAgent(
+                    model_config=ModelConfig(model='test-model'),
+                    runtime_config=AgentRuntimeConfig(cwd=workspace),
+                )
+                list_result = agent.run('/agents')
+                detail_result = agent.run('/agents show reviewer')
+        self.assertIn('# Agents', list_result.final_output)
+        self.assertIn('reviewer [projectSettings]', list_result.final_output)
+        self.assertIn('# Agent: reviewer', detail_result.final_output)
+        self.assertIn('Inspect code changes and summarize risks.', detail_result.final_output)
+
     def test_mcp_and_resource_commands_render_local_reports(self) -> None:
         with tempfile.TemporaryDirectory() as tmp_dir:
             workspace = Path(tmp_dir)

tests/test_main.py

@@ -213,6 +213,14 @@ class MainCliTests(unittest.TestCase):
         self.assertEqual(args.command, 'token-budget')
         self.assertEqual(args.cwd, '.')
 
+    def test_parser_accepts_agents_command(self) -> None:
+        parser = build_parser()
+        args = parser.parse_args(['agents', 'reviewer', '--cwd', '.', '--all'])
+        self.assertEqual(args.command, 'agents')
+        self.assertEqual(args.agent_type, 'reviewer')
+        self.assertTrue(args.all)
+        self.assertEqual(args.cwd, '.')
+
     def test_parser_accepts_team_runtime_commands(self) -> None:
         parser = build_parser()
         args = parser.parse_args(['team-create', 'reviewers', '--member', 'alice', '--cwd', '.'])