Improve WebUI streaming and Python tooling

tests/test_python_exec_tool.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import sys
 import tempfile
 from pathlib import Path
 from unittest import TestCase
@@ -29,6 +30,97 @@ class PythonExecToolTests(TestCase):
         self.assertEqual(result.metadata.get('action'), 'python_exec')
         self.assertEqual(result.metadata.get('mode'), 'code')
 
+    def test_python_exec_exposes_session_scratchpad(self) -> None:
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            root = Path(tmp_dir)
+            scratchpad = (root / 'session' / 'scratchpad').resolve()
+            scratchpad.mkdir(parents=True)
+            config = AgentRuntimeConfig(
+                cwd=root,
+                permissions=AgentPermissions(allow_shell_commands=True),
+            )
+            context = build_tool_context(config, scratchpad_directory=scratchpad)
+            result = execute_tool(
+                default_tool_registry(),
+                'python_exec',
+                {'code': 'import os\nprint(os.environ["PYTHON_EXEC_SCRATCHPAD"])'},
+                context,
+            )
+
+        self.assertTrue(result.ok)
+        self.assertIn(str(scratchpad), result.content)
+        self.assertEqual(result.metadata.get('scratchpad_directory'), str(scratchpad))
+
+    def test_python_exec_prefers_user_python_env(self) -> None:
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            root = Path(tmp_dir)
+            user_env = (root / 'account' / 'python' / '.venv').resolve()
+            bin_dir = user_env / 'bin'
+            bin_dir.mkdir(parents=True)
+            python_bin = bin_dir / 'python'
+            try:
+                python_bin.symlink_to(sys.executable)
+            except OSError:
+                python_bin.write_text(
+                    '#!/bin/sh\nexec "$PYTHON_EXEC_TEST_REAL_PYTHON" "$@"\n',
+                    encoding='utf-8',
+                )
+                python_bin.chmod(0o755)
+            config = AgentRuntimeConfig(
+                cwd=root,
+                permissions=AgentPermissions(allow_shell_commands=True),
+                python_env_dir=user_env,
+            )
+            context = build_tool_context(
+                config,
+                extra_env={'PYTHON_EXEC_TEST_REAL_PYTHON': sys.executable},
+            )
+            result = execute_tool(
+                default_tool_registry(),
+                'python_exec',
+                {'code': 'import os, sys\nprint(sys.executable)\nprint(os.environ["PYTHON_EXEC_VENV"])'},
+                context,
+            )
+
+        self.assertTrue(result.ok)
+        self.assertIn(str(user_env), result.content)
+        self.assertEqual(result.metadata.get('python_env_dir'), str(user_env))
+
+    def test_python_package_show_uses_user_python_env(self) -> None:
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            root = Path(tmp_dir)
+            user_env = (root / 'account' / 'python' / '.venv').resolve()
+            bin_dir = user_env / 'bin'
+            bin_dir.mkdir(parents=True)
+            python_bin = bin_dir / 'python'
+            try:
+                python_bin.symlink_to(sys.executable)
+            except OSError:
+                python_bin.write_text(
+                    '#!/bin/sh\nexec "$PYTHON_EXEC_TEST_REAL_PYTHON" "$@"\n',
+                    encoding='utf-8',
+                )
+                python_bin.chmod(0o755)
+            config = AgentRuntimeConfig(
+                cwd=root,
+                permissions=AgentPermissions(allow_shell_commands=True),
+                python_env_dir=user_env,
+            )
+            context = build_tool_context(
+                config,
+                extra_env={'PYTHON_EXEC_TEST_REAL_PYTHON': sys.executable},
+            )
+            result = execute_tool(
+                default_tool_registry(),
+                'python_package',
+                {'action': 'show'},
+                context,
+            )
+
+        self.assertTrue(result.ok)
+        self.assertIn(str(user_env), result.content)
+        self.assertEqual(result.metadata.get('python_env_dir'), str(user_env))
+
     def test_python_exec_is_blocked_without_shell_permission(self) -> None:
         with tempfile.TemporaryDirectory() as tmp_dir:
             config = AgentRuntimeConfig(cwd=Path(tmp_dir))
@@ -67,4 +159,3 @@ class PythonExecToolTests(TestCase):
         self.assertTrue(result.ok)
         self.assertIn('a|b', result.content)
         self.assertEqual(result.metadata.get('mode'), 'script')
-