fix: Rename type to kind

.gitignore

@@ -8,3 +8,4 @@ __pycache__
 .venv
 coverage.xml
 .nox
+spec.json

development.md

@@ -0,0 +1,9 @@
+# Development
+
+## Type generation from spec
+
+<!-- TODO replace spec.json with the public url so we always get the latest version-->
+
+```bash
+uv run datamodel-codegen --input ./spec.json --input-file-type jsonschema --output ./src/a2a/types.py --target-python-version 3.10 --output-model-type pydantic_v2.BaseModel --disable-timestamp --use-schema-description --use-union-operator --use-field-description --use-default --use-default-kwarg --use-one-literal-as-default --class-name A2A --use-standard-collections
+```

examples/helloworld/test_client.py

@@ -18,7 +18,7 @@ async def main() -> None:
             'message': {
                 'role': 'user',
                 'parts': [
-                    {'type': 'text', 'text': 'how much is 10 USD in INR?'}
+                    {'kind': 'text', 'text': 'how much is 10 USD in INR?'}
                 ],
                 'messageId': uuid4().hex,
             },

examples/langgraph/test_client.py

@@ -26,7 +26,7 @@ def create_send_message_payload(
     payload: dict[str, Any] = {
         'message': {
             'role': 'user',
-            'parts': [{'type': 'text', 'text': text}],
+            'parts': [{'kind': 'text', 'text': text}],
             'messageId': uuid4().hex,
         },
     }

src/a2a/types.py

@@ -133,13 +133,13 @@ class DataPart(BaseModel):
     """
     Structured data content
     """
-    metadata: dict[str, Any] | None = None
+    kind: Literal['data'] = 'data'
     """
-    Optional metadata associated with the part.
+    Part type - data for DataParts
     """
-    type: Literal['data'] = 'data'
+    metadata: dict[str, Any] | None = None
     """
-    Part type - data for DataParts
+    Optional metadata associated with the part.
     """
 
 
@@ -577,11 +577,11 @@ class TaskState(Enum):
     submitted = 'submitted'
     working = 'working'
     input_required = 'input-required'
-    auth_required = 'auth-required'
     completed = 'completed'
     canceled = 'canceled'
     failed = 'failed'
     rejected = 'rejected'
+    auth_required = 'auth-required'
     unknown = 'unknown'
 
 
@@ -590,6 +590,10 @@ class TextPart(BaseModel):
     Represents a text segment within parts.
     """
 
+    kind: Literal['text'] = 'text'
+    """
+    Part type - text for TextParts
+    """
     metadata: dict[str, Any] | None = None
     """
     Optional metadata associated with the part.
@@ -598,10 +602,6 @@ class TextPart(BaseModel):
     """
     Text content
     """
-    type: Literal['text'] = 'text'
-    """
-    Part type - text for TextParts
-    """
 
 
 class UnsupportedOperationError(BaseModel):
@@ -745,13 +745,13 @@ class FilePart(BaseModel):
     """
     File content either as url or bytes
     """
-    metadata: dict[str, Any] | None = None
+    kind: Literal['file'] = 'file'
     """
-    Optional metadata associated with the part.
+    Part type - file for FileParts
     """
-    type: Literal['file'] = 'file'
+    metadata: dict[str, Any] | None = None
     """
-    Part type - file for FileParts
+    Optional metadata associated with the part.
     """
 
 
@@ -933,7 +933,7 @@ class SetTaskPushNotificationConfigSuccessResponse(BaseModel):
 
 class Artifact(BaseModel):
     """
-    Represents an artifact generated for a task.
+    Represents an artifact generated for a task task.
     """
 
     artifactId: str
@@ -959,9 +959,7 @@ class Artifact(BaseModel):
 
 
 class GetTaskPushNotificationConfigResponse(
-    RootModel[
-        JSONRPCErrorResponse | GetTaskPushNotificationConfigSuccessResponse
-    ]
+    RootModel[JSONRPCErrorResponse | GetTaskPushNotificationConfigSuccessResponse]
 ):
     root: JSONRPCErrorResponse | GetTaskPushNotificationConfigSuccessResponse
     """
@@ -978,9 +976,9 @@ class Message(BaseModel):
     """
     the context the message is associated with
     """
-    final: bool | None = None
+    kind: Literal['message'] = 'message'
     """
-    indicates the end of the event stream
+    event type
     """
     messageId: str
     """
@@ -1002,10 +1000,6 @@ class Message(BaseModel):
     """
     identifier of task the message is related to
     """
-    type: Literal['message'] = 'message'
-    """
-    event type
-    """
 
 
 class MessageSendParams(BaseModel):
@@ -1076,9 +1070,7 @@ class SendStreamingMessageRequest(BaseModel):
 
 
 class SetTaskPushNotificationConfigResponse(
-    RootModel[
-        JSONRPCErrorResponse | SetTaskPushNotificationConfigSuccessResponse
-    ]
+    RootModel[JSONRPCErrorResponse | SetTaskPushNotificationConfigSuccessResponse]
 ):
     root: JSONRPCErrorResponse | SetTaskPushNotificationConfigSuccessResponse
     """
@@ -1103,6 +1095,10 @@ class TaskArtifactUpdateEvent(BaseModel):
     """
     the context the task is associated with
     """
+    kind: Literal['artifact-update'] = 'artifact-update'
+    """
+    event type
+    """
     lastChunk: bool | None = None
     """
     Indicates if this is the last chunk of the artifact
@@ -1115,10 +1111,6 @@ class TaskArtifactUpdateEvent(BaseModel):
     """
     Task id
     """
-    type: Literal['artifact-update'] = 'artifact-update'
-    """
-    event type
-    """
 
 
 class TaskStatus(BaseModel):
@@ -1150,6 +1142,10 @@ class TaskStatusUpdateEvent(BaseModel):
     """
     indicates the end of the event stream
     """
+    kind: Literal['status-update'] = 'status-update'
+    """
+    event type
+    """
     metadata: dict[str, Any] | None = None
     """
     extension metadata
@@ -1162,10 +1158,6 @@ class TaskStatusUpdateEvent(BaseModel):
     """
     Task id
     """
-    type: Literal['status-update'] = 'status-update'
-    """
-    event type
-    """
 
 
 class A2ARequest(
@@ -1207,6 +1199,10 @@ class Task(BaseModel):
     """
     unique identifier for the task
     """
+    kind: Literal['task'] = 'task'
+    """
+    event type
+    """
     metadata: dict[str, Any] | None = None
     """
     extension metadata
@@ -1215,10 +1211,6 @@ class Task(BaseModel):
     """
     current status of the task
     """
-    type: Literal['task'] = 'task'
-    """
-    event type
-    """
 
 
 class CancelTaskSuccessResponse(BaseModel):
@@ -1301,9 +1293,7 @@ class SendStreamingMessageSuccessResponse(BaseModel):
     """
 
 
-class CancelTaskResponse(
-    RootModel[JSONRPCErrorResponse | CancelTaskSuccessResponse]
-):
+class CancelTaskResponse(RootModel[JSONRPCErrorResponse | CancelTaskSuccessResponse]):
     root: JSONRPCErrorResponse | CancelTaskSuccessResponse
     """
     JSON-RPC response for the 'tasks/cancel' method.
@@ -1342,9 +1332,7 @@ class JSONRPCResponse(
     """
 
 
-class SendMessageResponse(
-    RootModel[JSONRPCErrorResponse | SendMessageSuccessResponse]
-):
+class SendMessageResponse(RootModel[JSONRPCErrorResponse | SendMessageSuccessResponse]):
     root: JSONRPCErrorResponse | SendMessageSuccessResponse
     """
     JSON-RPC response model for the 'message/send' method.

tests/client/test_client.py

@@ -63,14 +63,14 @@
     'id': 'task-abc',
     'contextId': 'session-xyz',
     'status': {'state': 'working'},
-    'type': 'task',
+    'kind': 'task',
 }
 
 MINIMAL_CANCELLED_TASK: dict[str, Any] = {
     'id': 'task-abc',
     'contextId': 'session-xyz',
     'status': {'state': 'canceled'},
-    'type': 'task',
+    'kind': 'task',
 }
 
 
@@ -237,7 +237,7 @@
         client = A2AClient(
             httpx_client=mock_httpx_client,
             agent_card=mock_agent_card,
             url='http://otherurl.com',
         )
         assert (
             client.url == mock_agent_card.url

tests/server/events/test_event_consumer.py

@@ -28,7 +28,7 @@
     'id': '123',
     'contextId': 'session-xyz',
     'status': {'state': 'submitted'},
-    'type': 'task',
+    'kind': 'task',
 }
 
 MESSAGE_PAYLOAD: dict[str, Any] = {

tests/server/events/test_event_queue.py

@@ -21,7 +21,7 @@
     'id': '123',
     'contextId': 'session-xyz',
     'status': {'state': 'submitted'},
-    'type': 'task',
+    'kind': 'task',
 }
 MESSAGE_PAYLOAD: dict[str, Any] = {
     'role': 'agent',

tests/server/request_handlers/test_jsonrpc_handler.py

@@ -62,7 +62,7 @@
     'id': 'task_123',
     'contextId': 'session-xyz',
     'status': {'state': 'submitted'},
-    'type': 'task',
+    'kind': 'task',
 }
 MESSAGE_PAYLOAD: dict[str, Any] = {
     'role': 'agent',

tests/server/tasks/test_inmemory_task_store.py

@@ -10,7 +10,7 @@
     'id': 'task-abc',
     'contextId': 'session-xyz',
     'status': {'state': 'submitted'},
-    'type': 'task',
+    'kind': 'task',
 }
 
 

tests/server/tasks/test_task_manager.py

@@ -22,7 +22,7 @@
     'id': 'task-abc',
     'contextId': 'session-xyz',
     'status': {'state': 'submitted'},
-    'type': 'task',
+    'kind': 'task',
 }
 
 
@@ -205,7 +205,7 @@ async def test_save_task_event_new_task_no_task_id(
         'id': 'new-task-id',
         'contextId': 'some-context',
         'status': {'state': 'working'},
-        'type': 'task',
+        'kind': 'task',
     }
     task = Task(**task_data)
     await task_manager_without_id.save_task_event(task)