feat: Convert fields in types.py to use snake_case

pyproject.toml

@@ -43,7 +43,7 @@ grpc = ["grpcio>=1.60", "grpcio-tools>=1.60", "grpcio_reflection>=1.7.0", "proto
 homepage = "https://a2a-protocol.org/"
 repository = "https://github.com/a2aproject/a2a-python"
 changelog = "https://github.com/a2aproject/a2a-python/blob/main/CHANGELOG.md"
-documentation = "https://a2a-protocol.org/latest/sdk/python/"
+documentation = "https://a2a-protocol.org/sdk/python/"
 
 [tool.hatch.build.targets.wheel]
 packages = ["src/a2a"]
@@ -96,6 +96,9 @@ url = "https://test.pypi.org/simple/"
 publish-url = "https://test.pypi.org/legacy/"
 explicit = true
 
+[tool.mypy]
+plugins = ['pydantic.mypy']
+
 [tool.pyright]
 include = ["src"]
 exclude = [

scripts/generate_types.sh

@@ -33,7 +33,10 @@ uv run datamodel-codegen \
   --class-name A2A \
   --use-standard-collections \
   --use-subclass-enum \
-  --base-class a2a._base.A2ABaseModel
+  --base-class a2a._base.A2ABaseModel \
+  --field-constraints \
+  --snake-case-field \
+  --no-alias
 
 echo "Formatting generated file with ruff..."
 uv run ruff format "$GENERATED_FILE"

src/a2a/_base.py

@@ -1,4 +1,21 @@
 from pydantic import BaseModel, ConfigDict
+from pydantic.alias_generators import to_camel
+
+
+def to_camel_custom(snake: str) -> str:
+    """Convert a snake_case string to camelCase.
+
+    Args:
+        snake: The string to convert.
+
+    Returns:
+        The converted camelCase string.
+    """
+    # First, remove any trailing underscores. This is common for names that
+    # conflict with Python keywords, like 'in_' or 'from_'.
+    if snake.endswith('_'):
+        snake = snake.rstrip('_')
+    return to_camel(snake)
 
 
 class A2ABaseModel(BaseModel):
@@ -12,4 +29,6 @@ class A2ABaseModel(BaseModel):
         # SEE: https://docs.pydantic.dev/latest/api/config/#pydantic.config.ConfigDict.populate_by_name
         validate_by_name=True,
         validate_by_alias=True,
+        serialize_by_alias=True,
+        alias_generator=to_camel_custom,
     )

src/a2a/client/auth/interceptor.py

@@ -36,7 +36,7 @@ async def intercept(
         if (
             agent_card is None
             or agent_card.security is None
-            or agent_card.securitySchemes is None
+            or agent_card.security_schemes is None
         ):
             return request_payload, http_kwargs
 
@@ -45,8 +45,8 @@ async def intercept(
                 credential = await self._credential_service.get_credentials(
                     scheme_name, context
                 )
-                if credential and scheme_name in agent_card.securitySchemes:
-                    scheme_def_union = agent_card.securitySchemes.get(
+                if credential and scheme_name in agent_card.security_schemes:
+                    scheme_def_union = agent_card.security_schemes.get(
                         scheme_name
                     )
                     if not scheme_def_union:

src/a2a/client/helpers.py

@@ -15,8 +15,8 @@ def create_text_message_object(
         content: The text content of the message. Defaults to an empty string.
 
     Returns:
-        A `Message` object with a new UUID messageId.
+        A `Message` object with a new UUID message_id.
     """
     return Message(
-        role=role, parts=[Part(TextPart(text=content))], messageId=str(uuid4())
+        role=role, parts=[Part(TextPart(text=content))], message_id=str(uuid4())
     )

src/a2a/server/agent_execution/context.py

@@ -53,14 +53,14 @@ def __init__(  # noqa: PLR0913
         # match the request. Otherwise, create them
         if self._params:
             if task_id:
-                self._params.message.taskId = task_id
+                self._params.message.task_id = task_id
                 if task and task.id != task_id:
                     raise ServerError(InvalidParamsError(message='bad task id'))
             else:
                 self._check_or_generate_task_id()
             if context_id:
-                self._params.message.contextId = context_id
-                if task and task.contextId != context_id:
+                self._params.message.context_id = context_id
+                if task and task.context_id != context_id:
                     raise ServerError(
                         InvalidParamsError(message='bad context id')
                     )
@@ -148,17 +148,17 @@ def _check_or_generate_task_id(self) -> None:
         if not self._params:
             return
 
-        if not self._task_id and not self._params.message.taskId:
-            self._params.message.taskId = str(uuid.uuid4())
-        if self._params.message.taskId:
-            self._task_id = self._params.message.taskId
+        if not self._task_id and not self._params.message.task_id:
+            self._params.message.task_id = str(uuid.uuid4())
+        if self._params.message.task_id:
+            self._task_id = self._params.message.task_id
 
     def _check_or_generate_context_id(self) -> None:
         """Ensures a context ID is present, generating one if necessary."""
         if not self._params:
             return
 
-        if not self._context_id and not self._params.message.contextId:
-            self._params.message.contextId = str(uuid.uuid4())
-        if self._params.message.contextId:
-            self._context_id = self._params.message.contextId
+        if not self._context_id and not self._params.message.context_id:
+            self._params.message.context_id = str(uuid.uuid4())
+        if self._params.message.context_id:
+            self._context_id = self._params.message.context_id

src/a2a/server/agent_execution/simple_request_context_builder.py

@@ -18,7 +18,7 @@
 
         Args:
             should_populate_referred_tasks: If True, the builder will fetch tasks
-                referenced in `params.message.referenceTaskIds` and populate the
+                referenced in `params.message.reference_task_ids` and populate the
                 `related_tasks` field in the RequestContext. Defaults to False.
             task_store: The TaskStore instance to use for fetching referred tasks.
                 Required if `should_populate_referred_tasks` is True.
@@ -26,43 +26,43 @@
         self._task_store = task_store
         self._should_populate_referred_tasks = should_populate_referred_tasks
 
     async def build(
         self,
         params: MessageSendParams | None = None,
         task_id: str | None = None,
         context_id: str | None = None,
         task: Task | None = None,
         context: ServerCallContext | None = None,
     ) -> RequestContext:
         """Builds the request context for an agent execution.
 
         This method assembles the RequestContext object. If the builder was
         initialized with `should_populate_referred_tasks=True`, it fetches all tasks
-        referenced in `params.message.referenceTaskIds` from the `task_store`.
+        referenced in `params.message.reference_task_ids` from the `task_store`.
 
         Args:
             params: The parameters of the incoming message send request.
             task_id: The ID of the task being executed.
             context_id: The ID of the current execution context.
             task: The primary task object associated with the request.
             context: The server call context, containing metadata about the call.
 
         Returns:
             An instance of RequestContext populated with the provided information
             and potentially a list of related tasks.
         """
         related_tasks: list[Task] | None = None
 
         if (
             self._task_store
             and self._should_populate_referred_tasks
             and params
-            and params.message.referenceTaskIds
+            and params.message.reference_task_ids
         ):
             tasks = await asyncio.gather(
                 *[
                     self._task_store.get(task_id)
-                    for task_id in params.message.referenceTaskIds
+                    for task_id in params.message.reference_task_ids
                 ]
             )
             related_tasks = [x for x in tasks if x is not None]

src/a2a/server/apps/jsonrpc/fastapi_app.py

@@ -89,7 +89,7 @@ def add_routes_to_app(
         )(self._handle_requests)
         app.get(agent_card_url)(self._handle_get_agent_card)
 
-        if self.agent_card.supportsAuthenticatedExtendedCard:
+        if self.agent_card.supports_authenticated_extended_card:
             app.get(extended_agent_card_url)(
                 self._handle_get_authenticated_extended_agent_card
             )

src/a2a/server/apps/jsonrpc/jsonrpc_app.py

@@ -135,11 +135,11 @@ def __init__(
             agent_card=agent_card, request_handler=http_handler
         )
         if (
-            self.agent_card.supportsAuthenticatedExtendedCard
+            self.agent_card.supports_authenticated_extended_card
             and self.extended_agent_card is None
         ):
             logger.error(
-                'AgentCard.supportsAuthenticatedExtendedCard is True, but no extended_agent_card was provided. The /agent/authenticatedExtendedCard endpoint will return 404.'
+                'AgentCard.supports_authenticated_extended_card is True, but no extended_agent_card was provided. The /agent/authenticatedExtendedCard endpoint will return 404.'
             )
         self._context_builder = context_builder or DefaultCallContextBuilder()
 
@@ -421,7 +421,7 @@ async def _handle_get_authenticated_extended_agent_card(
         self, request: Request
     ) -> JSONResponse:
         """Handles GET requests for the authenticated extended agent card."""
-        if not self.agent_card.supportsAuthenticatedExtendedCard:
+        if not self.agent_card.supports_authenticated_extended_card:
             return JSONResponse(
                 {'error': 'Extended agent card not supported or not enabled.'},
                 status_code=404,
@@ -435,7 +435,7 @@ async def _handle_get_authenticated_extended_agent_card(
                     by_alias=True,
                 )
             )
-        # If supportsAuthenticatedExtendedCard is true, but no specific
+        # If supports_authenticated_extended_card is true, but no specific
         # extended_agent_card was provided during server initialization,
         # return a 404
         return JSONResponse(

src/a2a/server/apps/jsonrpc/starlette_app.py

@@ -86,7 +86,7 @@ def routes(
             ),
         ]
 
-        if self.agent_card.supportsAuthenticatedExtendedCard:
+        if self.agent_card.supports_authenticated_extended_card:
             app_routes.append(
                 Route(
                     extended_agent_card_url,

src/a2a/server/models.py

@@ -123,7 +123,7 @@ class TaskMixin:
     """Mixin providing standard task columns with proper type handling."""
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, index=True)
-    contextId: Mapped[str] = mapped_column(String(36), nullable=False)  # noqa: N815
+    context_id: Mapped[str] = mapped_column(String(36), nullable=False)
     kind: Mapped[str] = mapped_column(
         String(16), nullable=False, default='task'
     )
@@ -148,12 +148,12 @@ def task_metadata(cls) -> Mapped[dict[str, Any] | None]:
     def __repr__(self) -> str:
         """Return a string representation of the task."""
         repr_template = (
-            '<{CLS}(id="{ID}", contextId="{CTX_ID}", status="{STATUS}")>'
+            '<{CLS}(id="{ID}", context_id="{CTX_ID}", status="{STATUS}")>'
         )
         return repr_template.format(
             CLS=self.__class__.__name__,
             ID=self.id,
-            CTX_ID=self.contextId,
+            CTX_ID=self.context_id,
             STATUS=self.status,
         )
 
@@ -188,11 +188,11 @@ class TaskModel(TaskMixin, base):
         @override
         def __repr__(self) -> str:
             """Return a string representation of the task."""
-            repr_template = '<TaskModel[{TABLE}](id="{ID}", contextId="{CTX_ID}", status="{STATUS}")>'
+            repr_template = '<TaskModel[{TABLE}](id="{ID}", context_id="{CTX_ID}", status="{STATUS}")>'
             return repr_template.format(
                 TABLE=table_name,
                 ID=self.id,
-                CTX_ID=self.contextId,
+                CTX_ID=self.context_id,
                 STATUS=self.status,
             )
 

src/a2a/server/request_handlers/default_request_handler.py

@@ -122,25 +122,25 @@
         """
         task: Task | None = await self.task_store.get(params.id)
         if not task:
             raise ServerError(error=TaskNotFoundError())
 
         task_manager = TaskManager(
             task_id=task.id,
-            context_id=task.contextId,
+            context_id=task.context_id,
             task_store=self.task_store,
             initial_message=None,
         )
         result_aggregator = ResultAggregator(task_manager)
 
         queue = await self._queue_manager.tap(task.id)
         if not queue:
             queue = EventQueue()
 
         await self.agent_executor.cancel(
             RequestContext(
                 None,
                 task_id=task.id,
-                context_id=task.contextId,
+                context_id=task.context_id,
                 task=task,
             ),
             queue,
@@ -184,8 +184,8 @@
         """
         # Create task manager and validate existing task
         task_manager = TaskManager(
-            task_id=params.message.taskId,
-            context_id=params.message.contextId,
+            task_id=params.message.task_id,
+            context_id=params.message.context_id,
             task_store=self.task_store,
             initial_message=params.message,
         )
@@ -205,7 +205,7 @@
         request_context = await self._request_context_builder.build(
             params=params,
             task_id=task.id if task else None,
-            context_id=params.message.contextId,
+            context_id=params.message.context_id,
             task=task,
             context=context,
         )
@@ -218,10 +218,10 @@
         if (
             self._push_config_store
             and params.configuration
-            and params.configuration.pushNotificationConfig
+            and params.configuration.push_notification_config
         ):
             await self._push_config_store.set_info(
-                task_id, params.configuration.pushNotificationConfig
+                task_id, params.configuration.push_notification_config
             )
 
         queue = await self._queue_manager.create_or_tap(task_id)
@@ -366,13 +366,13 @@
         if not self._push_config_store:
             raise ServerError(error=UnsupportedOperationError())
 
-        task: Task | None = await self.task_store.get(params.taskId)
+        task: Task | None = await self.task_store.get(params.task_id)
         if not task:
             raise ServerError(error=TaskNotFoundError())
 
         await self._push_config_store.set_info(
-            params.taskId,
-            params.pushNotificationConfig,
+            params.task_id,
+            params.push_notification_config,
         )
 
         return params
@@ -404,7 +404,8 @@
             )
 
         return TaskPushNotificationConfig(
-            taskId=params.id, pushNotificationConfig=push_notification_config[0]
+            task_id=params.id,
+            push_notification_config=push_notification_config[0],
         )
 
     async def on_resubscribe_to_task(
@@ -425,21 +426,21 @@
             raise ServerError(
                 error=InvalidParamsError(
                     message=f'Task {task.id} is in terminal state: {task.status.state}'
                 )
             )
 
         task_manager = TaskManager(
             task_id=task.id,
-            context_id=task.contextId,
+            context_id=task.context_id,
             task_store=self.task_store,
             initial_message=None,
         )
 
         result_aggregator = ResultAggregator(task_manager)
 
         queue = await self._queue_manager.tap(task.id)
         if not queue:
             raise ServerError(error=TaskNotFoundError())
 
         consumer = EventConsumer(queue)
         async for event in result_aggregator.consume_and_emit(consumer):
@@ -470,7 +471,7 @@
             for config in push_notification_config_list:
                 task_push_notification_config.append(
                     TaskPushNotificationConfig(
-                        taskId=params.id, pushNotificationConfig=config
+                        task_id=params.id, push_notification_config=config
                     )
                 )
 
@@ -493,5 +494,5 @@
             raise ServerError(error=TaskNotFoundError())
 
         await self._push_config_store.delete_info(
-            params.id, params.pushNotificationConfigId
+            params.id, params.push_notification_config_id
         )

src/a2a/server/request_handlers/grpc_handler.py

@@ -232,7 +232,7 @@ async def GetTaskPushNotificationConfig(
         return a2a_pb2.TaskPushNotificationConfig()
 
     @validate(
-        lambda self: self.agent_card.capabilities.pushNotifications,
+        lambda self: self.agent_card.capabilities.push_notifications,
         'Push notifications are not supported by the agent',
     )
     async def CreateTaskPushNotificationConfig(

src/a2a/server/request_handlers/jsonrpc_handler.py

@@ -255,7 +255,7 @@ async def get_push_notification_config(
             )
 
     @validate(
-        lambda self: self.agent_card.capabilities.pushNotifications,
+        lambda self: self.agent_card.capabilities.push_notifications,
         'Push notifications are not supported by the agent',
     )
     async def set_push_notification_config(

src/a2a/server/tasks/database_task_store.py

@@ -95,7 +95,7 @@ def _to_orm(self, task: Task) -> TaskModel:
         """Maps a Pydantic Task to a SQLAlchemy TaskModel instance."""
         return self.task_model(
             id=task.id,
-            contextId=task.contextId,
+            context_id=task.context_id,
             kind=task.kind,
             status=task.status,
             artifacts=task.artifacts,
@@ -108,7 +108,7 @@ def _from_orm(self, task_model: TaskModel) -> Task:
         # Map database columns to Pydantic model fields
         task_data_from_db = {
             'id': task_model.id,
-            'contextId': task_model.contextId,
+            'context_id': task_model.context_id,
             'kind': task_model.kind,
             'status': task_model.status,
             'artifacts': task_model.artifacts,