chore: remove init=False from default literals

Remove `init=False` from default literals to improve compatibility with
existing code.

Minimise changes by using literal strings instead of enum.

Author: stevenh

python-sdk/ag_ui/core/events.py

@@ -3,10 +3,11 @@
 """
 
 from enum import Enum
-from typing import Any, List, Literal, Optional, Union, Annotated
+from typing import Annotated, Any, List, Literal, Optional, Union
+
 from pydantic import Field
 
-from .types import Message, State, ConfiguredBaseModel, Role
+from .types import ConfiguredBaseModel, Message, State
 
 
 class EventType(str, Enum):
@@ -46,16 +47,16 @@ class TextMessageStartEvent(BaseEvent):
     """
     Event indicating the start of a text message.
     """
-    type: Literal[EventType.TEXT_MESSAGE_START] = Field(EventType.TEXT_MESSAGE_START, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TEXT_MESSAGE_START] = EventType.TEXT_MESSAGE_START  # pyright: ignore[reportIncompatibleVariableOverride]
     message_id: str
-    role: Literal[Role.ASSISTANT] = Field(Role.ASSISTANT, init=False)
+    role: Literal["assistant"] = "assistant"
 
 
 class TextMessageContentEvent(BaseEvent):
     """
     Event containing a piece of text message content.
     """
-    type: Literal[EventType.TEXT_MESSAGE_CONTENT] = Field(EventType.TEXT_MESSAGE_CONTENT, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TEXT_MESSAGE_CONTENT] = EventType.TEXT_MESSAGE_CONTENT  # pyright: ignore[reportIncompatibleVariableOverride]
     message_id: str
     delta: str = Field(min_length=1)
 
@@ -64,14 +65,14 @@ class TextMessageEndEvent(BaseEvent):
     """
     Event indicating the end of a text message.
     """
-    type: Literal[EventType.TEXT_MESSAGE_END] = Field(EventType.TEXT_MESSAGE_END, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TEXT_MESSAGE_END] = EventType.TEXT_MESSAGE_END  # pyright: ignore[reportIncompatibleVariableOverride]
     message_id: str
 
 class TextMessageChunkEvent(BaseEvent):
     """
     Event containing a chunk of text message content.
     """
-    type: Literal[EventType.TEXT_MESSAGE_CHUNK] = Field(EventType.TEXT_MESSAGE_CHUNK, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TEXT_MESSAGE_CHUNK] = EventType.TEXT_MESSAGE_CHUNK  # pyright: ignore[reportIncompatibleVariableOverride]
     message_id: Optional[str] = None
     role: Optional[Literal["assistant"]] = None
     delta: Optional[str] = None
@@ -80,7 +81,7 @@ class ToolCallStartEvent(BaseEvent):
     """
     Event indicating the start of a tool call.
     """
-    type: Literal[EventType.TOOL_CALL_START] = Field(EventType.TOOL_CALL_START, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TOOL_CALL_START] = EventType.TOOL_CALL_START  # pyright: ignore[reportIncompatibleVariableOverride]
     tool_call_id: str
     tool_call_name: str
     parent_message_id: Optional[str] = None
@@ -90,7 +91,7 @@ class ToolCallArgsEvent(BaseEvent):
     """
     Event containing tool call arguments.
     """
-    type: Literal[EventType.TOOL_CALL_ARGS] = Field(EventType.TOOL_CALL_ARGS, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TOOL_CALL_ARGS] = EventType.TOOL_CALL_ARGS  # pyright: ignore[reportIncompatibleVariableOverride]
     tool_call_id: str
     delta: str
 
@@ -99,14 +100,14 @@ class ToolCallEndEvent(BaseEvent):
     """
     Event indicating the end of a tool call.
     """
-    type: Literal[EventType.TOOL_CALL_END] = Field(EventType.TOOL_CALL_END, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TOOL_CALL_END] = EventType.TOOL_CALL_END  # pyright: ignore[reportIncompatibleVariableOverride]
     tool_call_id: str
 
 class ToolCallChunkEvent(BaseEvent):
     """
     Event containing a chunk of tool call content.
     """
-    type: Literal[EventType.TOOL_CALL_CHUNK] = Field(EventType.TOOL_CALL_CHUNK, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.TOOL_CALL_CHUNK] = EventType.TOOL_CALL_CHUNK  # pyright: ignore[reportIncompatibleVariableOverride]
     tool_call_id: Optional[str] = None
     tool_call_name: Optional[str] = None
     parent_message_id: Optional[str] = None
@@ -116,31 +117,31 @@ class StateSnapshotEvent(BaseEvent):
     """
     Event containing a snapshot of the state.
     """
-    type: Literal[EventType.STATE_SNAPSHOT] = Field(EventType.STATE_SNAPSHOT, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.STATE_SNAPSHOT] = EventType.STATE_SNAPSHOT  # pyright: ignore[reportIncompatibleVariableOverride]
     snapshot: State
 
 
 class StateDeltaEvent(BaseEvent):
     """
     Event containing a delta of the state.
     """
-    type: Literal[EventType.STATE_DELTA] = Field(EventType.STATE_DELTA, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.STATE_DELTA] = EventType.STATE_DELTA  # pyright: ignore[reportIncompatibleVariableOverride]
     delta: List[Any]  # JSON Patch (RFC 6902)
 
 
 class MessagesSnapshotEvent(BaseEvent):
     """
     Event containing a snapshot of the messages.
     """
-    type: Literal[EventType.MESSAGES_SNAPSHOT] = Field(EventType.MESSAGES_SNAPSHOT, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.MESSAGES_SNAPSHOT] = EventType.MESSAGES_SNAPSHOT  # pyright: ignore[reportIncompatibleVariableOverride]
     messages: List[Message]
 
 
 class RawEvent(BaseEvent):
     """
     Event containing a raw event.
     """
-    type: Literal[EventType.RAW] = Field(EventType.RAW, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.RAW] = EventType.RAW  # pyright: ignore[reportIncompatibleVariableOverride]
     event: Any
     source: Optional[str] = None
 
@@ -149,7 +150,7 @@ class CustomEvent(BaseEvent):
     """
     Event containing a custom event.
     """
-    type: Literal[EventType.CUSTOM] = Field(EventType.CUSTOM, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.CUSTOM] = EventType.CUSTOM  # pyright: ignore[reportIncompatibleVariableOverride]
     name: str
     value: Any
 
@@ -158,7 +159,7 @@ class RunStartedEvent(BaseEvent):
     """
     Event indicating that a run has started.
     """
-    type: Literal[EventType.RUN_STARTED] = Field(EventType.RUN_STARTED, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.RUN_STARTED] = EventType.RUN_STARTED  # pyright: ignore[reportIncompatibleVariableOverride]
     thread_id: str
     run_id: str
 
@@ -167,7 +168,7 @@ class RunFinishedEvent(BaseEvent):
     """
     Event indicating that a run has finished.
     """
-    type: Literal[EventType.RUN_FINISHED] = Field(EventType.RUN_FINISHED, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.RUN_FINISHED] = EventType.RUN_FINISHED  # pyright: ignore[reportIncompatibleVariableOverride]
     thread_id: str
     run_id: str
 
@@ -176,7 +177,7 @@ class RunErrorEvent(BaseEvent):
     """
     Event indicating that a run has encountered an error.
     """
-    type: Literal[EventType.RUN_ERROR] = Field(EventType.RUN_ERROR, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.RUN_ERROR] = EventType.RUN_ERROR  # pyright: ignore[reportIncompatibleVariableOverride]
     message: str
     code: Optional[str] = None
 
@@ -185,15 +186,15 @@ class StepStartedEvent(BaseEvent):
     """
     Event indicating that a step has started.
     """
-    type: Literal[EventType.STEP_STARTED] = Field(EventType.STEP_STARTED, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.STEP_STARTED] = EventType.STEP_STARTED  # pyright: ignore[reportIncompatibleVariableOverride]
     step_name: str
 
 
 class StepFinishedEvent(BaseEvent):
     """
     Event indicating that a step has finished.
     """
-    type: Literal[EventType.STEP_FINISHED] = Field(EventType.STEP_FINISHED, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal[EventType.STEP_FINISHED] = EventType.STEP_FINISHED  # pyright: ignore[reportIncompatibleVariableOverride]
     step_name: str
 
 

python-sdk/ag_ui/core/types.py

@@ -2,21 +2,10 @@
 This module contains the types for the Agent User Interaction Protocol Python SDK.
 """
 
-from enum import Enum
-from typing import Any, List, Literal, Optional, Union, Annotated
-from pydantic import BaseModel, Field, ConfigDict
-from pydantic.alias_generators import to_camel
-
+from typing import Annotated, Any, List, Literal, Optional, Union
 
-class Role(str, Enum):
-    """
-    The role of an actor.
-    """
-    DEVELOPER = "developer"
-    SYSTEM = "system"
-    ASSISTANT = "assistant"
-    USER = "user"
-    TOOL = "tool"
+from pydantic import BaseModel, ConfigDict, Field
+from pydantic.alias_generators import to_camel
 
 
 class ConfiguredBaseModel(BaseModel):
@@ -44,7 +33,7 @@ class ToolCall(ConfiguredBaseModel):
     A tool call, modelled after OpenAI tool calls.
     """
     id: str
-    type: Literal["function"] = Field("function", init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    type: Literal["function"] = "function"  # pyright: ignore[reportIncompatibleVariableOverride]
     function: FunctionCall
 
 
@@ -62,30 +51,31 @@ class DeveloperMessage(BaseMessage):
     """
     A developer message.
     """
-    role: Literal[Role.DEVELOPER] = Field(Role.DEVELOPER, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    role: Literal["developer"] = "developer"  # pyright: ignore[reportIncompatibleVariableOverride]
     content: str
 
 
 class SystemMessage(BaseMessage):
     """
     A system message.
     """
-    role: Literal[Role.SYSTEM] = Field(Role.SYSTEM, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    role: Literal["system"] = "system"  # pyright: ignore[reportIncompatibleVariableOverride]
     content: str
 
 
 class AssistantMessage(BaseMessage):
     """
     An assistant message.
     """
-    role: Literal[Role.ASSISTANT] = Field(Role.ASSISTANT, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    role: Literal["assistant"] = "assistant"  # pyright: ignore[reportIncompatibleVariableOverride]
     tool_calls: Optional[List[ToolCall]] = None
 
+
 class UserMessage(BaseMessage):
     """
     A user message.
     """
-    role: Literal[Role.USER] = Field(Role.USER, init=False)  # pyright: ignore[reportIncompatibleVariableOverride]
+    role: Literal["user"] = "user" # pyright: ignore[reportIncompatibleVariableOverride]
     content: str
 
 
@@ -94,7 +84,7 @@ class ToolMessage(ConfiguredBaseModel):
     A tool result message.
     """
     id: str
-    role: Literal[Role.TOOL] = Field(Role.TOOL, init=False)
+    role: Literal["tool"] = "tool"
     content: str
     tool_call_id: str
 
@@ -104,6 +94,8 @@ class ToolMessage(ConfiguredBaseModel):
     Field(discriminator="role")
 ]
 
+Role = Literal["developer", "system", "assistant", "user", "tool"]
+
 
 class Context(ConfiguredBaseModel):
     """