chore: Enforce unused-import linting with ruff and clean up src

.agents/skills/adk-unit-guide/SKILL.md

@@ -73,4 +73,4 @@ Use the following structure and instructions to create the guide for the code un
 
 - Mention any limitations of the code unit, if known.
 
-```
+```

.pre-commit-config.yaml

@@ -11,6 +11,12 @@ repos:
     rev: v2.24.0
     hooks:
       - id: pyproject-fmt
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.15.17
+    hooks:
+      - id: ruff
+        args: [--fix]
+        files: ^src/
   - repo: https://github.com/PyCQA/isort
     rev: 8.0.1
     hooks:

pyproject.toml

@@ -117,6 +117,7 @@ optional-dependencies.dev = [
   "pyink==25.12",
   "pylint>=2.6",
   "pyproject-fmt==2.24",
+  "ruff==0.15.17",
   "tox>=4.23.2",
   "tox-uv>=1.33.2",
 ]
@@ -260,6 +261,25 @@ module.include = [ "py.typed" ]
 sdist.include = [ "src/**/*", "README.md", "pyproject.toml", "LICENSE" ]
 sdist.exclude = [ "src/**/*.sh", "src/**/README.md" ]
 
+[tool.ruff]
+extend-exclude = [
+  "src/google/adk/cli/browser/",
+  # These hardcode googleapis.com endpoints and trip the check-file-contents
+  # mTLS policy check the moment they change. Excluded so unused-import
+  # cleanup does not pull them into a PR; clean them up when the mTLS policy
+  # is addressed.
+  "src/google/adk/integrations/bigquery/bigquery_credentials.py",
+  "src/google/adk/integrations/bigquery/data_insights_tool.py",
+  "src/google/adk/plugins/bigquery_agent_analytics_plugin.py",
+  "src/google/adk/tools/data_agent/data_agent_tool.py",
+  "src/google/adk/v1/",
+  "v1_tests/",
+]
+lint.select = [ "F401" ]
+# __init__.py files re-export symbols for the public API; unused imports
+# there are intentional, not dead code.
+lint.per-file-ignores."**/__init__.py" = [ "F401" ]
+
 [tool.isort]
 profile = "google"
 line_length = 200

scripts/run_precommit_checks.py

@@ -95,6 +95,11 @@ class HookSpec:
 # from its .pre-commit-hooks.yaml. The `local` hooks (addlicense,
 # check-new-py-prefix) are handled by _LOCAL_HOOKS below instead.
 _HOOK_SPECS: dict[str, HookSpec] = {
+    'ruff': HookSpec(
+        ['ruff', 'check', '--force-exclude'],
+        ['ruff', 'check', '--fix', '--force-exclude'],
+        _PY,
+    ),
     'isort': HookSpec(['isort', '--check-only', '--diff'], ['isort'], _PY),
     'pyink': HookSpec(['pyink', '--check', '--diff'], ['pyink'], _PY),
     'pyproject-fmt': HookSpec(
@@ -317,7 +322,11 @@ def run_standard_hook(
   if spec.is_fixer and not fix:
     return _run_fixer_in_check_mode(tool, files)
   command = spec.fix_cmd if (fix and spec.fix_cmd) else spec.check_cmd
-  return _run(command + hook.args, files)
+  # Drop `--fix` from the config args: check mode must not modify files, and
+  # fix mode already gets `--fix` from the spec's fix_cmd (passing it twice is
+  # an error, e.g. ruff rejects a repeated `--fix`).
+  args = [a for a in hook.args if a != '--fix']
+  return _run(command + args, files)
 
 
 # --- local hooks (no upstream tool; bespoke handling) -----------------------

src/google/adk/a2a/converters/from_adk_event.py

@@ -22,13 +22,11 @@
 from typing import Dict
 from typing import List
 from typing import Optional
-from typing import Tuple
 from typing import Union
 import uuid
 
 from a2a.server.events import Event as A2AEvent
 from a2a.types import Artifact
-from a2a.types import DataPart
 from a2a.types import Message
 from a2a.types import Part as A2APart
 from a2a.types import Role
@@ -39,11 +37,7 @@
 from a2a.types import TextPart
 
 from ...events.event import Event
-from ...flows.llm_flows.functions import REQUEST_EUC_FUNCTION_CALL_NAME
 from ..experimental import a2a_experimental
-from .part_converter import A2A_DATA_PART_METADATA_IS_LONG_RUNNING_KEY
-from .part_converter import A2A_DATA_PART_METADATA_TYPE_FUNCTION_CALL
-from .part_converter import A2A_DATA_PART_METADATA_TYPE_KEY
 from .part_converter import convert_genai_part_to_a2a_part
 from .part_converter import GenAIPartToA2APartConverter
 from .utils import _get_adk_metadata_key

src/google/adk/a2a/converters/part_converter.py

@@ -20,7 +20,6 @@
 
 import base64
 from collections.abc import Callable
-import json
 import logging
 from typing import List
 from typing import Optional

src/google/adk/a2a/executor/a2a_agent_executor_impl.py

@@ -26,9 +26,7 @@
 from a2a.server.agent_execution import AgentExecutor
 from a2a.server.agent_execution.context import RequestContext
 from a2a.server.events.event_queue import EventQueue
-from a2a.types import Artifact
 from a2a.types import Message
-from a2a.types import Part
 from a2a.types import Role
 from a2a.types import Task
 from a2a.types import TaskState
@@ -49,7 +47,6 @@
 from ..experimental import a2a_experimental
 from .config import A2aAgentExecutorConfig
 from .executor_context import ExecutorContext
-from .interceptors.include_artifacts_in_a2a_event import include_artifacts_in_a2a_event_interceptor
 from .utils import execute_after_agent_interceptors
 from .utils import execute_after_event_interceptors
 from .utils import execute_before_agent_interceptors

src/google/adk/a2a/executor/config.py

@@ -36,7 +36,6 @@
 from ..converters.part_converter import GenAIPartToA2APartConverter
 from ..converters.request_converter import A2ARequestToAgentRunRequestConverter
 from ..converters.request_converter import convert_a2a_request_to_agent_run_request
-from ..converters.utils import _get_adk_metadata_key
 from ..experimental import a2a_experimental
 from .executor_context import ExecutorContext
 

src/google/adk/a2a/executor/utils.py

@@ -20,7 +20,7 @@
 from a2a.types import TaskStatusUpdateEvent
 
 from ...events.event import Event
-from ..converters.utils import _get_adk_metadata_key
+from ..converters.utils import _get_adk_metadata_key as _get_adk_metadata_key
 from .config import ExecuteInterceptor
 from .executor_context import ExecutorContext
 

src/google/adk/a2a/utils/agent_to_a2a.py

@@ -36,7 +36,6 @@
 from ...sessions.in_memory_session_service import InMemorySessionService
 from ...workflow import Workflow
 from ..executor.a2a_agent_executor import A2aAgentExecutor
-from ..executor.config import A2aAgentExecutorConfig
 from ..experimental import a2a_experimental
 from .agent_card_builder import AgentCardBuilder
 

src/google/adk/agents/base_agent_config.py

@@ -17,8 +17,6 @@
 from typing import List
 from typing import Literal
 from typing import Optional
-from typing import Type
-from typing import TYPE_CHECKING
 from typing import TypeVar
 from typing import Union
 

src/google/adk/agents/callback_context.py

@@ -15,8 +15,8 @@
 from __future__ import annotations
 
 from .context import Context
+
 # Keep ReadonlyContext for backward compatibility
-from .readonly_context import ReadonlyContext
 
 # CallbackContext is unified into Context
 CallbackContext = Context

src/google/adk/agents/context.py

@@ -28,7 +28,6 @@
 
 if TYPE_CHECKING:
   from google.genai import types
-  from pydantic import BaseModel
 
   from ..artifacts.base_artifact_service import ArtifactVersion
   from ..auth.auth_credential import AuthCredential
@@ -220,12 +219,13 @@ def __init__(
         parent_ctx.isolation_scope if parent_ctx else None
     )
 
+    self._output_for_ancestors: list[str]
     if use_as_output and parent_ctx:
-      self._output_for_ancestors: list[str] = [parent_ctx.node_path] + list(
+      self._output_for_ancestors = [parent_ctx.node_path] + list(
           parent_ctx._output_for_ancestors or []
       )
     else:
-      self._output_for_ancestors: list[str] = []
+      self._output_for_ancestors = []
     self._error: Exception | None = None
     self._error_node_path: str = ''
 

src/google/adk/agents/live_request_queue.py

@@ -20,7 +20,6 @@
 from google.genai import types
 from pydantic import BaseModel
 from pydantic import ConfigDict
-from pydantic import field_validator
 
 
 class LiveRequest(BaseModel):

src/google/adk/agents/llm/task/_finish_task_tool.py

@@ -28,7 +28,6 @@
 from ....tools.base_tool import BaseTool
 from ....utils._schema_utils import SchemaType
 from ._task_models import _DefaultTaskOutput
-from ._task_models import TaskResult
 
 if TYPE_CHECKING:
   from ....models.llm_request import LlmRequest

src/google/adk/agents/remote_a2a_agent.py

@@ -31,21 +31,17 @@
 from a2a.client.client import ClientConfig as A2AClientConfig
 from a2a.client.client_factory import ClientFactory as A2AClientFactory
 from a2a.client.errors import A2AClientHTTPError
-from a2a.client.middleware import ClientCallContext
 from a2a.types import AgentCard
 from a2a.types import Message as A2AMessage
-from a2a.types import MessageSendConfiguration
 from a2a.types import Part as A2APart
 from a2a.types import Role
-from a2a.types import Task as A2ATask
 from a2a.types import TaskArtifactUpdateEvent as A2ATaskArtifactUpdateEvent
 from a2a.types import TaskState
 from a2a.types import TaskStatusUpdateEvent as A2ATaskStatusUpdateEvent
 from a2a.types import TransportProtocol as A2ATransport
 from google.adk.platform import uuid as platform_uuid
 from google.genai import types as genai_types
 import httpx
-from pydantic import BaseModel
 
 try:
   from a2a.utils.constants import AGENT_CARD_WELL_KNOWN_PATH
@@ -68,7 +64,6 @@
 from ..a2a.converters.to_adk_event import _create_mock_function_call_for_required_user_input
 from ..a2a.converters.to_adk_event import MOCK_FUNCTION_CALL_FOR_REQUIRED_USER_AUTH
 from ..a2a.converters.to_adk_event import MOCK_FUNCTION_CALL_FOR_REQUIRED_USER_INPUT
-from ..a2a.converters.utils import _get_adk_metadata_key
 from ..a2a.experimental import a2a_experimental
 from ..a2a.logs.log_utils import build_a2a_request_log
 from ..a2a.logs.log_utils import build_a2a_response_log

src/google/adk/apps/base_events_summarizer.py

@@ -16,8 +16,6 @@
 import abc
 from typing import Optional
 
-from google.genai.types import Content
-
 from ..events.event import Event
 from ..utils.feature_decorator import experimental
 

src/google/adk/apps/llm_event_summarizer.py

@@ -15,7 +15,6 @@
 
 from typing import Optional
 
-from google.genai import types
 from google.genai.types import Content
 from google.genai.types import Part
 

src/google/adk/artifacts/base_artifact_service.py

@@ -15,7 +15,6 @@
 
 from abc import ABC
 from abc import abstractmethod
-from datetime import datetime
 import logging
 from typing import Any
 from typing import Optional

src/google/adk/auth/credential_manager.py

@@ -35,7 +35,6 @@
 from .auth_tool import AuthConfig
 from .base_auth_provider import BaseAuthProvider
 from .exchanger.base_credential_exchanger import BaseCredentialExchanger
-from .exchanger.base_credential_exchanger import ExchangeResult
 from .exchanger.credential_exchanger_registry import CredentialExchangerRegistry
 from .oauth2_discovery import OAuth2DiscoveryManager
 from .refresher.credential_refresher_registry import CredentialRefresherRegistry

src/google/adk/auth/exchanger/oauth2_credential_exchanger.py

@@ -34,7 +34,7 @@
 from .base_credential_exchanger import ExchangeResult
 
 try:
-  from authlib.integrations.requests_client import OAuth2Session
+  from authlib.integrations.requests_client import OAuth2Session  # noqa: F401
 
   AUTHLIB_AVAILABLE = True
 except ImportError:

src/google/adk/auth/refresher/oauth2_credential_refresher.py

@@ -16,7 +16,6 @@
 
 from __future__ import annotations
 
-import json
 import logging
 from typing import Optional
 
@@ -25,8 +24,6 @@
 from google.adk.auth.oauth2_credential_util import create_oauth2_session
 from google.adk.auth.oauth2_credential_util import update_credential_with_tokens
 from google.adk.utils.feature_decorator import experimental
-from google.auth.transport.requests import Request
-from google.oauth2.credentials import Credentials
 from typing_extensions import override
 
 from .base_credential_refresher import BaseCredentialRefresher

src/google/adk/cli/adk_web_server.py

@@ -18,8 +18,8 @@
 
 from typing_extensions import deprecated
 
-from .api_server import _parse_cors_origins
-from .api_server import RunAgentRequest
+from .api_server import _parse_cors_origins as _parse_cors_origins
+from .api_server import RunAgentRequest as RunAgentRequest
 from .dev_server import DevServer
 from .utils.base_agent_loader import BaseAgentLoader as BaseAgentLoader
 

src/google/adk/cli/agent_test_runner.py

@@ -728,11 +728,9 @@ def rebuild_tests(path: str):
   """Discovers test files and rebuilds them by running the agent live."""
   import json
   import sys
-  import time
 
   from google.adk.apps.app import App
   from google.adk.events.event import Event as AdkEvent
-  from google.genai import types
 
   path_obj = Path(path)
   if path_obj.is_dir():

src/google/adk/cli/built_in_agents/tools/delete_files.py

@@ -17,7 +17,6 @@
 from __future__ import annotations
 
 from datetime import datetime
-from pathlib import Path
 import shutil
 from typing import Any
 from typing import Dict

src/google/adk/cli/built_in_agents/tools/read_files.py

@@ -16,7 +16,6 @@
 
 from __future__ import annotations
 
-from pathlib import Path
 from typing import Any
 from typing import Dict
 from typing import List

src/google/adk/cli/cli_tools_click.py

@@ -963,7 +963,7 @@ def cli_eval(
   logs.setup_adk_logger(getattr(logging, log_level.upper()))
 
   try:
-    import importlib
+    import importlib  # noqa: F401
 
     from ..evaluation.base_eval_service import InferenceConfig
     from ..evaluation.base_eval_service import InferenceRequest
@@ -1215,14 +1215,14 @@ def cli_optimize(
   logs.setup_adk_logger(getattr(logging, log_level.upper()))
 
   try:
-    from ..evaluation.custom_metric_evaluator import _CustomMetricEvaluator
+    from ..evaluation.custom_metric_evaluator import _CustomMetricEvaluator  # noqa: F401
     from ..evaluation.local_eval_sets_manager import LocalEvalSetsManager
     from ..optimization.gepa_root_agent_prompt_optimizer import GEPARootAgentPromptOptimizer
     from ..optimization.gepa_root_agent_prompt_optimizer import GEPARootAgentPromptOptimizerConfig
     from ..optimization.local_eval_sampler import LocalEvalSampler
     from ..optimization.local_eval_sampler import LocalEvalSamplerConfig
-    from .cli_eval import _collect_eval_results
-    from .cli_eval import _collect_inferences
+    from .cli_eval import _collect_eval_results  # noqa: F401
+    from .cli_eval import _collect_inferences  # noqa: F401
     from .cli_eval import get_root_agent
 
   except ModuleNotFoundError as mnf:

src/google/adk/cli/conformance/cli_test.py

@@ -17,7 +17,6 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from enum import Enum
 from pathlib import Path
 import textwrap
 from typing import Optional