Python SDK Reference¶

This page contains SDK documentation for the a2a-sdk Python package.

pip install a2a-sdk

Client¶

Client-side components for interacting with an A2A agent.

`ClientEvent = tuple[Task, UpdateEvent]` `module-attribute` ¶

`Consumer = Callable[[ClientEvent | Message, AgentCard], Coroutine[None, Any, Any]]` `module-attribute` ¶

`logger = logging.getLogger(name)` `module-attribute` ¶

`A2ACardResolver` ¶

Agent Card resolver.

`agent_card_path = agent_card_path.lstrip('/')` `instance-attribute` ¶

`base_url = base_url.rstrip('/')` `instance-attribute` ¶

`httpx_client = httpx_client` `instance-attribute` ¶

`get_agent_card(relative_card_path=None, http_kwargs=None)` `async` ¶

Fetches an agent card from a specified path relative to the base_url.

If relative_card_path is None, it defaults to the resolver's configured agent_card_path (for the public agent card).

Parameters:

Name	Type	Description	Default
`relative_card_path`	`str \| None`	Optional path to the agent card endpoint, relative to the base URL. If None, uses the default public agent card path.	`None`
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.get request.	`None`

Returns:

Type	Description
`AgentCard`	An `AgentCard` object representing the agent's capabilities.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated against the AgentCard schema.

`A2AClient` ¶

[DEPRECATED] Backwards compatibility wrapper for the JSON-RPC client.

`cancel_task(request, *, http_kwargs=None, context=None)` `async` ¶

Requests the agent to cancel a specific task.

Parameters:

Name	Type	Description	Default
`request`	`CancelTaskRequest`	The `CancelTaskRequest` object specifying the task ID.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`CancelTaskResponse`	A `CancelTaskResponse` object containing the updated Task with canceled status or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`get_card(*, http_kwargs=None, context=None)` `async` ¶

Retrieves the authenticated card (if necessary) or the public one.

Parameters:

Name	Type	Description	Default
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`AgentCard`	A `AgentCard` object containing the card or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`get_task(request, *, http_kwargs=None, context=None)` `async` ¶

Retrieves the current state and history of a specific task.

Parameters:

Name	Type	Description	Default
`request`	`GetTaskRequest`	The `GetTaskRequest` object specifying the task ID and history length.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`GetTaskResponse`	A `GetTaskResponse` object containing the Task or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`get_task_callback(request, *, http_kwargs=None, context=None)` `async` ¶

Retrieves the push notification configuration for a specific task.

Parameters:

Name	Type	Description	Default
`request`	`GetTaskPushNotificationConfigRequest`	The `GetTaskPushNotificationConfigRequest` object specifying the task ID.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`GetTaskPushNotificationConfigResponse`	A `GetTaskPushNotificationConfigResponse` object containing the configuration or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`resubscribe(request, *, http_kwargs=None, context=None)` `async` ¶

Reconnects to get task updates.

This method uses Server-Sent Events (SSE) to receive a stream of updates from the agent.

Parameters:

Name	Type	Description	Default
`request`	`TaskResubscriptionRequest`	The `TaskResubscriptionRequest` object containing the task information to reconnect to.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request. A default `timeout=None` is set but can be overridden.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Yields:

Type	Description
`AsyncGenerator[SendStreamingMessageResponse, None]`	`SendStreamingMessageResponse` objects as they are received in the SSE stream.
`AsyncGenerator[SendStreamingMessageResponse, None]`	These can be Task, Message, TaskStatusUpdateEvent, or TaskArtifactUpdateEvent.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP or SSE protocol error occurs during the request.
`A2AClientJSONError`	If an SSE event data cannot be decoded as JSON or validated.

`send_message(request, *, http_kwargs=None, context=None)` `async` ¶

Sends a non-streaming message request to the agent.

Parameters:

Name	Type	Description	Default
`request`	`SendMessageRequest`	The `SendMessageRequest` object containing the message and configuration.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`SendMessageResponse`	A `SendMessageResponse` object containing the agent's response (Task or Message) or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`send_message_streaming(request, *, http_kwargs=None, context=None)` `async` ¶

Sends a streaming message request to the agent and yields responses as they arrive.

This method uses Server-Sent Events (SSE) to receive a stream of updates from the agent.

Parameters:

Name	Type	Description	Default
`request`	`SendStreamingMessageRequest`	The `SendStreamingMessageRequest` object containing the message and configuration.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request. A default `timeout=None` is set but can be overridden.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Yields:

Type	Description
`AsyncGenerator[SendStreamingMessageResponse, None]`	`SendStreamingMessageResponse` objects as they are received in the SSE stream.
`AsyncGenerator[SendStreamingMessageResponse, None]`	These can be Task, Message, TaskStatusUpdateEvent, or TaskArtifactUpdateEvent.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP or SSE protocol error occurs during the request.
`A2AClientJSONError`	If an SSE event data cannot be decoded as JSON or validated.

`set_task_callback(request, *, http_kwargs=None, context=None)` `async` ¶

Sets or updates the push notification configuration for a specific task.

Parameters:

Name	Type	Description	Default
`request`	`SetTaskPushNotificationConfigRequest`	The `SetTaskPushNotificationConfigRequest` object specifying the task ID and configuration.	required
`http_kwargs`	`dict[str, Any] \| None`	Optional dictionary of keyword arguments to pass to the underlying httpx.post request.	`None`
`context`	`ClientCallContext \| None`	The client call context.	`None`

Returns:

Type	Description
`SetTaskPushNotificationConfigResponse`	A `SetTaskPushNotificationConfigResponse` object containing the confirmation or an error.

Raises:

Type	Description
`A2AClientHTTPError`	If an HTTP error occurs during the request.
`A2AClientJSONError`	If the response body cannot be decoded as JSON or validated.

`A2AClientError` ¶

Bases: Exception

Base exception for A2A Client errors.

`A2AClientHTTPError` ¶

Bases: A2AClientError

Client exception for HTTP errors received from the server.

`message = message` `instance-attribute` ¶

`status_code = status_code` `instance-attribute` ¶

`A2AClientJSONError` ¶

Bases: A2AClientError

Client exception for JSON errors during response parsing or validation.

`message = message` `instance-attribute` ¶

`A2AClientTimeoutError` ¶

Bases: A2AClientError

Client exception for timeout errors during a request.

`message = message` `instance-attribute` ¶

`A2AGrpcClient` ¶

Placeholder for A2AGrpcClient when dependencies are not installed.

`AuthInterceptor` ¶

Bases: ClientCallInterceptor

An interceptor that automatically adds authentication details to requests.

Based on the agent's security schemes.

`intercept(method_name, request_payload, http_kwargs, agent_card, context)` `async` ¶

Applies authentication headers to the request if credentials are available.

`Client` ¶

Bases: ABC

Abstract base class defining the interface for an A2A client.

This class provides a standard set of methods for interacting with an A2A agent, regardless of the underlying transport protocol (e.g., gRPC, JSON-RPC). It supports sending messages, managing tasks, and handling event streams.

`add_event_consumer(consumer)` `async` ¶

Attaches additional consumers to the Client.

`add_request_middleware(middleware)` `async` ¶

Attaches additional middleware to the Client.

`cancel_task(request, *, context=None)` `abstractmethod` `async` ¶

Requests the agent to cancel a specific task.

`consume(event, card)` `async` ¶

Processes the event via all the registered Consumers.

`get_card(*, context=None)` `abstractmethod` `async` ¶

Retrieves the agent's card.

`get_task(request, *, context=None)` `abstractmethod` `async` ¶

Retrieves the current state and history of a specific task.

`get_task_callback(request, *, context=None)` `abstractmethod` `async` ¶

Retrieves the push notification configuration for a specific task.

`resubscribe(request, *, context=None)` `abstractmethod` `async` ¶

Resubscribes to a task's event stream.

`send_message(request, *, context=None)` `abstractmethod` `async` ¶

Sends a message to the server.

This will automatically use the streaming or non-streaming approach as supported by the server and the client config. Client will aggregate update events and return an iterator of (Task,Update) pairs, or a Message. Client will also send these values to any configured Consumers in the client.

`set_task_callback(request, *, context=None)` `abstractmethod` `async` ¶

Sets or updates the push notification configuration for a specific task.

`ClientCallContext` ¶

Bases: BaseModel

A context passed with each client call, allowing for call-specific.

configuration and data passing. Such as authentication details or request deadlines.

`state = Field(default_factory=dict)` `class-attribute` `instance-attribute` ¶

`ClientCallInterceptor` ¶

Bases: ABC

An abstract base class for client-side call interceptors.

Interceptors can inspect and modify requests before they are sent, which is ideal for concerns like authentication, logging, or tracing.

`intercept(method_name, request_payload, http_kwargs, agent_card, context)` `abstractmethod` `async` ¶

Intercepts a client call before the request is sent.

Parameters:

Name	Type	Description	Default
`method_name`	`str`	The name of the RPC method (e.g., 'message/send').	required
`request_payload`	`dict[str, Any]`	The JSON RPC request payload dictionary.	required
`http_kwargs`	`dict[str, Any]`	The keyword arguments for the httpx request.	required
`agent_card`	`AgentCard \| None`	The AgentCard associated with the client.	required
`context`	`ClientCallContext \| None`	The ClientCallContext for this specific call.	required

Returns:

Type	Description
`dict[str, Any]`	A tuple containing the (potentially modified) request_payload
`dict[str, Any]`	and http_kwargs.

`ClientConfig` `dataclass` ¶

Configuration class for the A2AClient Factory.

`accepted_output_modes = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

The set of accepted output modes for the client.

`grpc_channel_factory = None` `class-attribute` `instance-attribute` ¶

Generates a grpc connection channel for a given url.

`httpx_client = None` `class-attribute` `instance-attribute` ¶

Http client to use to connect to agent.

`polling = False` `class-attribute` `instance-attribute` ¶

Whether client prefers to poll for updates from message:send. It is the callers job to check if the response is completed and if not run a polling loop.

`push_notification_configs = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

Push notification callbacks to use for every request.

`streaming = True` `class-attribute` `instance-attribute` ¶

Whether client supports streaming

`supported_transports = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

Ordered list of transports for connecting to agent (in order of preference). Empty implies JSONRPC only.

This is a string type to allow custom transports to exist in closed ecosystems.

`use_client_preference = False` `class-attribute` `instance-attribute` ¶

Whether to use client transport preferences over server preferences. Recommended to use server preferences in most situations.

`ClientFactory` ¶

ClientFactory is used to generate the appropriate client for the agent.

The factory is configured with a ClientConfig and optionally a list of Consumers to use for all generated Clients. The expected use is:

factory = ClientFactory(config, consumers)

Optionally register custom client implementations¶

factory.register('my_customer_transport', NewCustomTransportClient)

Then with an agent card make a client with additional consumers and¶

interceptors¶

client = factory.create(card, additional_consumers, interceptors)

Now the client can be used the same regardless of transport and¶

aligns client config with server capabilities.¶

`create(card, consumers=None, interceptors=None)` ¶

Create a new Client for the provided AgentCard.

Parameters:

Name	Type	Description	Default
`card`	`AgentCard`	An `AgentCard` defining the characteristics of the agent.	required
`consumers`	`list[Consumer] \| None`	A list of `Consumer` methods to pass responses to.	`None`
`interceptors`	`list[ClientCallInterceptor] \| None`	A list of interceptors to use for each request. These are used for things like attaching credentials or http headers to all outbound requests.	`None`

Returns:

Type	Description
`Client`	A `Client` object.

`register(label, generator)` ¶

Register a new transport producer for a given transport label.

`CredentialService` ¶

Bases: ABC

An abstract service for retrieving credentials.

`get_credentials(security_scheme_name, context)` `abstractmethod` `async` ¶

Retrieves a credential (e.g., token) for a security scheme.

`InMemoryContextCredentialStore` ¶

Bases: CredentialService

A simple in-memory store for session-keyed credentials.

This class uses the 'sessionId' from the ClientCallContext state to store and retrieve credentials...

`get_credentials(security_scheme_name, context)` `async` ¶

Retrieves credentials from the in-memory store.

Parameters:

Name	Type	Description	Default
`security_scheme_name`	`str`	The name of the security scheme.	required
`context`	`ClientCallContext \| None`	The client call context.	required

Returns:

Type	Description
`str \| None`	The credential string, or None if not found.

`set_credentials(session_id, security_scheme_name, credential)` `async` ¶

Method to populate the store.

`create_text_message_object(role=Role.user, content='')` ¶

Create a Message object containing a single TextPart.

Parameters:

Name	Type	Description	Default
`role`	`Role`	The role of the message sender (user or agent). Defaults to Role.user.	`user`
`content`	`str`	The text content of the message. Defaults to an empty string.	`''`

Returns:

Type	Description
`Message`	A `Message` object with a new UUID message_id.

`minimal_agent_card(url, transports=None)` ¶

Generates a minimal card to simplify bootstrapping client creation.

This minimal card is not viable itself to interact with the remote agent. Instead this is a short hand way to take a known url and transport option and interact with the get card endpoint of the agent server to get the correct agent card. This pattern is necessary for gRPC based card access as typically these servers won't expose a well known path card.

Server¶

Server-side components for implementing an A2A agent.

Types¶

`A2A` ¶

Bases: RootModel[Any]

`root` `instance-attribute` ¶

`A2AError` ¶

`root` `instance-attribute` ¶

A discriminated union of all standard JSON-RPC and A2A-specific error types.

`A2ARequest` ¶

`root` `instance-attribute` ¶

A discriminated union representing all possible JSON-RPC 2.0 requests supported by the A2A specification.

`APIKeySecurityScheme` ¶

Bases: A2ABaseModel

Defines a security scheme using an API key.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`in_` `instance-attribute` ¶

The location of the API key.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name` `instance-attribute` ¶

The name of the header, query, or cookie parameter to be used.

`type = 'apiKey'` `class-attribute` `instance-attribute` ¶

The type of the security scheme. Must be 'apiKey'.

`AgentCapabilities` ¶

Bases: A2ABaseModel

Defines optional capabilities supported by an agent.

`extensions = None` `class-attribute` `instance-attribute` ¶

A list of protocol extensions supported by the agent.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notifications = None` `class-attribute` `instance-attribute` ¶

Indicates if the agent supports sending push notifications for asynchronous task updates.

`state_transition_history = None` `class-attribute` `instance-attribute` ¶

Indicates if the agent provides a history of state transitions for a task.

`streaming = None` `class-attribute` `instance-attribute` ¶

Indicates if the agent supports Server-Sent Events (SSE) for streaming responses.

`AgentCard` ¶

Bases: A2ABaseModel

The AgentCard is a self-describing manifest for an agent. It provides essential metadata including the agent's identity, capabilities, skills, supported communication methods, and security requirements.

`additional_interfaces = None` `class-attribute` `instance-attribute` ¶

A list of additional supported interfaces (transport and URL combinations). This allows agents to expose multiple transports, potentially at different URLs.

Best practices: - SHOULD include all supported transports for completeness - SHOULD include an entry matching the main 'url' and 'preferredTransport' - MAY reuse URLs if multiple transports are available at the same endpoint - MUST accurately declare the transport available at each URL

Clients can select any interface from this list based on their transport capabilities and preferences. This enables transport negotiation and fallback scenarios.

`capabilities` `instance-attribute` ¶

A declaration of optional capabilities supported by the agent.

`default_input_modes` `instance-attribute` ¶

Default set of supported input MIME types for all skills, which can be overridden on a per-skill basis.

`default_output_modes` `instance-attribute` ¶

Default set of supported output MIME types for all skills, which can be overridden on a per-skill basis.

`description = Field(..., examples=['Agent that helps users with recipes and cooking.'])` `class-attribute` `instance-attribute` ¶

A human-readable description of the agent, assisting users and other agents in understanding its purpose.

`documentation_url = None` `class-attribute` `instance-attribute` ¶

An optional URL to the agent's documentation.

`icon_url = None` `class-attribute` `instance-attribute` ¶

An optional URL to an icon for the agent.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name = Field(..., examples=['Recipe Agent'])` `class-attribute` `instance-attribute` ¶

A human-readable name for the agent.

`preferred_transport = Field(default='JSONRPC', examples=['JSONRPC', 'GRPC', 'HTTP+JSON'])` `class-attribute` `instance-attribute` ¶

The transport protocol for the preferred endpoint (the main 'url' field). If not specified, defaults to 'JSONRPC'.

IMPORTANT: The transport specified here MUST be available at the main 'url'. This creates a binding between the main URL and its supported transport protocol. Clients should prefer this transport and URL combination when both are supported.

`protocol_version = '0.3.0'` `class-attribute` `instance-attribute` ¶

The version of the A2A protocol this agent supports.

`provider = None` `class-attribute` `instance-attribute` ¶

Information about the agent's service provider.

`security = Field(default=None, examples=[[{'oauth': ['read']}, {'api-key': [], 'mtls': []}]])` `class-attribute` `instance-attribute` ¶

A list of security requirement objects that apply to all agent interactions. Each object lists security schemes that can be used. Follows the OpenAPI 3.0 Security Requirement Object. This list can be seen as an OR of ANDs. Each object in the list describes one possible set of security requirements that must be present on a request. This allows specifying, for example, "callers must either use OAuth OR an API Key AND mTLS."

`security_schemes = None` `class-attribute` `instance-attribute` ¶

A declaration of the security schemes available to authorize requests. The key is the scheme name. Follows the OpenAPI 3.0 Security Scheme Object.

`signatures = None` `class-attribute` `instance-attribute` ¶

JSON Web Signatures computed for this AgentCard.

`skills` `instance-attribute` ¶

The set of skills, or distinct capabilities, that the agent can perform.

`supports_authenticated_extended_card = None` `class-attribute` `instance-attribute` ¶

If true, the agent can provide an extended agent card with additional details to authenticated users. Defaults to false.

`url = Field(..., examples=['https://api.example.com/a2a/v1'])` `class-attribute` `instance-attribute` ¶

The preferred endpoint URL for interacting with the agent. This URL MUST support the transport specified by 'preferredTransport'.

`version = Field(..., examples=['1.0.0'])` `class-attribute` `instance-attribute` ¶

The agent's own version number. The format is defined by the provider.

`AgentCardSignature` ¶

Bases: A2ABaseModel

AgentCardSignature represents a JWS signature of an AgentCard. This follows the JSON format of an RFC 7515 JSON Web Signature (JWS).

`header = None` `class-attribute` `instance-attribute` ¶

The unprotected JWS header values.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`protected` `instance-attribute` ¶

The protected JWS header for the signature. This is a Base64url-encoded JSON object, as per RFC 7515.

`signature` `instance-attribute` ¶

The computed signature, Base64url-encoded.

`AgentExtension` ¶

Bases: A2ABaseModel

A declaration of a protocol extension supported by an Agent.

`description = None` `class-attribute` `instance-attribute` ¶

A human-readable description of how this agent uses the extension.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params = None` `class-attribute` `instance-attribute` ¶

Optional, extension-specific configuration parameters.

`required = None` `class-attribute` `instance-attribute` ¶

If true, the client must understand and comply with the extension's requirements to interact with the agent.

`uri` `instance-attribute` ¶

The unique URI identifying the extension.

`AgentInterface` ¶

Bases: A2ABaseModel

Declares a combination of a target URL and a transport protocol for interacting with the agent. This allows agents to expose the same functionality over multiple transport mechanisms.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`transport = Field(..., examples=['JSONRPC', 'GRPC', 'HTTP+JSON'])` `class-attribute` `instance-attribute` ¶

The transport protocol supported at this URL.

`url = Field(..., examples=['https://api.example.com/a2a/v1', 'https://grpc.example.com/a2a', 'https://rest.example.com/v1'])` `class-attribute` `instance-attribute` ¶

The URL where this interface is available. Must be a valid absolute HTTPS URL in production.

`AgentProvider` ¶

Bases: A2ABaseModel

Represents the service provider of an agent.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`organization` `instance-attribute` ¶

The name of the agent provider's organization.

`url` `instance-attribute` ¶

A URL for the agent provider's website or relevant documentation.

`AgentSkill` ¶

Bases: A2ABaseModel

Represents a distinct capability or function that an agent can perform.

`description` `instance-attribute` ¶

A detailed description of the skill, intended to help clients or users understand its purpose and functionality.

`examples = Field(default=None, examples=[['I need a recipe for bread']])` `class-attribute` `instance-attribute` ¶

Example prompts or scenarios that this skill can handle. Provides a hint to the client on how to use the skill.

`id` `instance-attribute` ¶

A unique identifier for the agent's skill.

`input_modes = None` `class-attribute` `instance-attribute` ¶

The set of supported input MIME types for this skill, overriding the agent's defaults.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name` `instance-attribute` ¶

A human-readable name for the skill.

`output_modes = None` `class-attribute` `instance-attribute` ¶

The set of supported output MIME types for this skill, overriding the agent's defaults.

`security = Field(default=None, examples=[[{'google': ['oidc']}]])` `class-attribute` `instance-attribute` ¶

Security schemes necessary for the agent to leverage this skill. As in the overall AgentCard.security, this list represents a logical OR of security requirement objects. Each object is a set of security schemes that must be used together (a logical AND).

`tags = Field(..., examples=[['cooking', 'customer support', 'billing']])` `class-attribute` `instance-attribute` ¶

A set of keywords describing the skill's capabilities.

`Artifact` ¶

Bases: A2ABaseModel

Represents a file, data structure, or other resource generated by an agent during a task.

`artifact_id` `instance-attribute` ¶

A unique identifier (e.g. UUID) for the artifact within the scope of the task.

`description = None` `class-attribute` `instance-attribute` ¶

An optional, human-readable description of the artifact.

`extensions = None` `class-attribute` `instance-attribute` ¶

The URIs of extensions that are relevant to this artifact.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions. The key is an extension-specific identifier.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name = None` `class-attribute` `instance-attribute` ¶

An optional, human-readable name for the artifact.

`parts` `instance-attribute` ¶

An array of content parts that make up the artifact.

`AuthenticatedExtendedCardNotConfiguredError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the agent does not have an Authenticated Extended Card configured

`code = -32007` `class-attribute` `instance-attribute` ¶

The error code for when an authenticated extended card is not configured.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Authenticated Extended Card is not configured'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`AuthorizationCodeOAuthFlow` ¶

Bases: A2ABaseModel

Defines configuration details for the OAuth 2.0 Authorization Code flow.

`authorization_url` `instance-attribute` ¶

The authorization URL to be used for this flow. This MUST be a URL and use TLS.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`refresh_url = None` `class-attribute` `instance-attribute` ¶

The URL to be used for obtaining refresh tokens. This MUST be a URL and use TLS.

`scopes` `instance-attribute` ¶

The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it.

`token_url` `instance-attribute` ¶

The token URL to be used for this flow. This MUST be a URL and use TLS.

`CancelTaskRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/cancel method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/cancel'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/cancel'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters identifying the task to cancel.

`CancelTaskResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | CancelTaskSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/cancel method.

`CancelTaskSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/cancel method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, containing the final state of the canceled Task object.

`ClientCredentialsOAuthFlow` ¶

Bases: A2ABaseModel

Defines configuration details for the OAuth 2.0 Client Credentials flow.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`refresh_url = None` `class-attribute` `instance-attribute` ¶

The URL to be used for obtaining refresh tokens. This MUST be a URL.

`scopes` `instance-attribute` ¶

The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it.

`token_url` `instance-attribute` ¶

The token URL to be used for this flow. This MUST be a URL.

`ContentTypeNotSupportedError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating an incompatibility between the requested content types and the agent's capabilities.

`code = -32005` `class-attribute` `instance-attribute` ¶

The error code for an unsupported content type.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Incompatible content types'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`DataPart` ¶

Bases: A2ABaseModel

Represents a structured data segment (e.g., JSON) within a message or artifact.

`data` `instance-attribute` ¶

The structured data content.

`kind = 'data'` `class-attribute` `instance-attribute` ¶

The type of this part, used as a discriminator. Always 'data'.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with this part.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`DeleteTaskPushNotificationConfigParams` ¶

Bases: A2ABaseModel

Defines parameters for deleting a specific push notification configuration for a task.

`id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with the request.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notification_config_id` `instance-attribute` ¶

The ID of the push notification configuration to delete.

`DeleteTaskPushNotificationConfigRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/pushNotificationConfig/delete method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/pushNotificationConfig/delete'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/pushNotificationConfig/delete'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters identifying the push notification configuration to delete.

`DeleteTaskPushNotificationConfigResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | DeleteTaskPushNotificationConfigSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/pushNotificationConfig/delete method.

`DeleteTaskPushNotificationConfigSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/pushNotificationConfig/delete method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result is null on successful deletion.

`FileBase` ¶

Bases: A2ABaseModel

Defines base properties for a file.

`mime_type = None` `class-attribute` `instance-attribute` ¶

The MIME type of the file (e.g., "application/pdf").

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name = None` `class-attribute` `instance-attribute` ¶

An optional name for the file (e.g., "document.pdf").

`FilePart` ¶

Bases: A2ABaseModel

Represents a file segment within a message or artifact. The file content can be provided either directly as bytes or as a URI.

`file` `instance-attribute` ¶

The file content, represented as either a URI or as base64-encoded bytes.

`kind = 'file'` `class-attribute` `instance-attribute` ¶

The type of this part, used as a discriminator. Always 'file'.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with this part.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`FileWithBytes` ¶

Bases: A2ABaseModel

Represents a file with its content provided directly as a base64-encoded string.

`bytes` `instance-attribute` ¶

The base64-encoded content of the file.

`mime_type = None` `class-attribute` `instance-attribute` ¶

The MIME type of the file (e.g., "application/pdf").

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name = None` `class-attribute` `instance-attribute` ¶

An optional name for the file (e.g., "document.pdf").

`FileWithUri` ¶

Bases: A2ABaseModel

Represents a file with its content located at a specific URI.

`mime_type = None` `class-attribute` `instance-attribute` ¶

The MIME type of the file (e.g., "application/pdf").

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name = None` `class-attribute` `instance-attribute` ¶

An optional name for the file (e.g., "document.pdf").

`uri` `instance-attribute` ¶

A URL pointing to the file's content.

`GetAuthenticatedExtendedCardRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the agent/getAuthenticatedExtendedCard method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'agent/getAuthenticatedExtendedCard'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'agent/getAuthenticatedExtendedCard'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`GetAuthenticatedExtendedCardResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | GetAuthenticatedExtendedCardSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the agent/getAuthenticatedExtendedCard method.

`GetAuthenticatedExtendedCardSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the agent/getAuthenticatedExtendedCard method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result is an Agent Card object.

`GetTaskPushNotificationConfigParams` ¶

Bases: A2ABaseModel

Defines parameters for fetching a specific push notification configuration for a task.

`id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with the request.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notification_config_id = None` `class-attribute` `instance-attribute` ¶

The ID of the push notification configuration to retrieve.

`GetTaskPushNotificationConfigRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/pushNotificationConfig/get method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/pushNotificationConfig/get'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/pushNotificationConfig/get'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters for getting a push notification configuration.

`GetTaskPushNotificationConfigResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | GetTaskPushNotificationConfigSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/pushNotificationConfig/get method.

`GetTaskPushNotificationConfigSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/pushNotificationConfig/get method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, containing the requested push notification configuration.

`GetTaskRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/get method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/get'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/get'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters for querying a task.

`GetTaskResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | GetTaskSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/get method.

`GetTaskSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/get method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, containing the requested Task object.

`HTTPAuthSecurityScheme` ¶

Bases: A2ABaseModel

Defines a security scheme using HTTP authentication.

`bearer_format = None` `class-attribute` `instance-attribute` ¶

A hint to the client to identify how the bearer token is formatted (e.g., "JWT"). This is primarily for documentation purposes.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`scheme` `instance-attribute` ¶

The name of the HTTP Authentication scheme to be used in the Authorization header, as defined in RFC7235 (e.g., "Bearer"). This value should be registered in the IANA Authentication Scheme registry.

`type = 'http'` `class-attribute` `instance-attribute` ¶

The type of the security scheme. Must be 'http'.

`ImplicitOAuthFlow` ¶

Bases: A2ABaseModel

Defines configuration details for the OAuth 2.0 Implicit flow.

`authorization_url` `instance-attribute` ¶

The authorization URL to be used for this flow. This MUST be a URL.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`refresh_url = None` `class-attribute` `instance-attribute` ¶

The URL to be used for obtaining refresh tokens. This MUST be a URL.

`scopes` `instance-attribute` ¶

The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it.

`In` ¶

Bases: str, Enum

The location of the API key.

`cookie = 'cookie'` `class-attribute` `instance-attribute` ¶

`header = 'header'` `class-attribute` `instance-attribute` ¶

`query = 'query'` `class-attribute` `instance-attribute` ¶

`InternalError` ¶

Bases: A2ABaseModel

An error indicating an internal error on the server.

`code = -32603` `class-attribute` `instance-attribute` ¶

The error code for an internal server error.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Internal error'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`InvalidAgentResponseError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the agent returned a response that does not conform to the specification for the current method.

`code = -32006` `class-attribute` `instance-attribute` ¶

The error code for an invalid agent response.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Invalid agent response'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`InvalidParamsError` ¶

Bases: A2ABaseModel

An error indicating that the method parameters are invalid.

`code = -32602` `class-attribute` `instance-attribute` ¶

The error code for an invalid parameters error.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Invalid parameters'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`InvalidRequestError` ¶

Bases: A2ABaseModel

An error indicating that the JSON sent is not a valid Request object.

`code = -32600` `class-attribute` `instance-attribute` ¶

The error code for an invalid request.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Request payload validation error'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`JSONParseError` ¶

Bases: A2ABaseModel

An error indicating that the server received invalid JSON.

`code = -32700` `class-attribute` `instance-attribute` ¶

The error code for a JSON parse error.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Invalid JSON payload'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`JSONRPCError` ¶

Bases: A2ABaseModel

Represents a JSON-RPC 2.0 Error object, included in an error response.

`code` `instance-attribute` ¶

A number that indicates the error type that occurred.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message` `instance-attribute` ¶

A string providing a short description of the error.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`JSONRPCErrorResponse` ¶

Bases: A2ABaseModel

Represents a JSON-RPC 2.0 Error Response object.

`error` `instance-attribute` ¶

An object describing the error that occurred.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`JSONRPCMessage` ¶

Bases: A2ABaseModel

Defines the base structure for any JSON-RPC 2.0 request, response, or notification.

`id = None` `class-attribute` `instance-attribute` ¶

A unique identifier established by the client. It must be a String, a Number, or null. The server must reply with the same value in the response. This property is omitted for notifications.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`JSONRPCRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC 2.0 Request object.

`id = None` `class-attribute` `instance-attribute` ¶

A unique identifier established by the client. It must be a String, a Number, or null. The server must reply with the same value in the response. This property is omitted for notifications.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method` `instance-attribute` ¶

A string containing the name of the method to be invoked.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params = None` `class-attribute` `instance-attribute` ¶

A structured value holding the parameter values to be used during the method invocation.

`JSONRPCResponse` ¶

`root` `instance-attribute` ¶

A discriminated union representing all possible JSON-RPC 2.0 responses for the A2A specification methods.

`JSONRPCSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC 2.0 Response object.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The value of this member is determined by the method invoked on the Server.

`ListTaskPushNotificationConfigParams` ¶

Bases: A2ABaseModel

Defines parameters for listing all push notification configurations associated with a task.

`id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with the request.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`ListTaskPushNotificationConfigRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/pushNotificationConfig/list method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/pushNotificationConfig/list'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/pushNotificationConfig/list'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters identifying the task whose configurations are to be listed.

`ListTaskPushNotificationConfigResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | ListTaskPushNotificationConfigSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/pushNotificationConfig/list method.

`ListTaskPushNotificationConfigSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/pushNotificationConfig/list method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, containing an array of all push notification configurations for the task.

`Message` ¶

Bases: A2ABaseModel

Represents a single message in the conversation between a user and an agent.

`context_id = None` `class-attribute` `instance-attribute` ¶

The context ID for this message, used to group related interactions.

`extensions = None` `class-attribute` `instance-attribute` ¶

The URIs of extensions that are relevant to this message.

`kind = 'message'` `class-attribute` `instance-attribute` ¶

The type of this object, used as a discriminator. Always 'message' for a Message.

`message_id` `instance-attribute` ¶

A unique identifier for the message, typically a UUID, generated by the sender.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions. The key is an extension-specific identifier.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`parts` `instance-attribute` ¶

An array of content parts that form the message body. A message can be composed of multiple parts of different types (e.g., text and files).

`reference_task_ids = None` `class-attribute` `instance-attribute` ¶

A list of other task IDs that this message references for additional context.

`role` `instance-attribute` ¶

Identifies the sender of the message. user for the client, agent for the service.

`task_id = None` `class-attribute` `instance-attribute` ¶

The ID of the task this message is part of. Can be omitted for the first message of a new task.

`MessageSendConfiguration` ¶

Bases: A2ABaseModel

Defines configuration options for a message/send or message/stream request.

`accepted_output_modes = None` `class-attribute` `instance-attribute` ¶

A list of output MIME types the client is prepared to accept in the response.

`blocking = None` `class-attribute` `instance-attribute` ¶

If true, the client will wait for the task to complete. The server may reject this if the task is long-running.

`history_length = None` `class-attribute` `instance-attribute` ¶

The number of most recent messages from the task's history to retrieve in the response.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notification_config = None` `class-attribute` `instance-attribute` ¶

Configuration for the agent to send push notifications for updates after the initial response.

`MessageSendParams` ¶

Bases: A2ABaseModel

Defines the parameters for a request to send a message to an agent. This can be used to create a new task, continue an existing one, or restart a task.

`configuration = None` `class-attribute` `instance-attribute` ¶

Optional configuration for the send request.

`message` `instance-attribute` ¶

The message object being sent to the agent.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`MethodNotFoundError` ¶

Bases: A2ABaseModel

An error indicating that the requested method does not exist or is not available.

`code = -32601` `class-attribute` `instance-attribute` ¶

The error code for a method not found error.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Method not found'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`MutualTLSSecurityScheme` ¶

Bases: A2ABaseModel

Defines a security scheme using mTLS authentication.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`type = 'mutualTLS'` `class-attribute` `instance-attribute` ¶

The type of the security scheme. Must be 'mutualTLS'.

`OAuth2SecurityScheme` ¶

Bases: A2ABaseModel

Defines a security scheme using OAuth 2.0.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`flows` `instance-attribute` ¶

An object containing configuration information for the supported OAuth 2.0 flows.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`oauth2_metadata_url = None` `class-attribute` `instance-attribute` ¶

URL to the oauth2 authorization server metadata RFC8414. TLS is required.

`type = 'oauth2'` `class-attribute` `instance-attribute` ¶

The type of the security scheme. Must be 'oauth2'.

`OAuthFlows` ¶

Bases: A2ABaseModel

Defines the configuration for the supported OAuth 2.0 flows.

`authorization_code = None` `class-attribute` `instance-attribute` ¶

Configuration for the OAuth Authorization Code flow. Previously called accessCode in OpenAPI 2.0.

`client_credentials = None` `class-attribute` `instance-attribute` ¶

Configuration for the OAuth Client Credentials flow. Previously called application in OpenAPI 2.0.

`implicit = None` `class-attribute` `instance-attribute` ¶

Configuration for the OAuth Implicit flow.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`password = None` `class-attribute` `instance-attribute` ¶

Configuration for the OAuth Resource Owner Password flow.

`OpenIdConnectSecurityScheme` ¶

Bases: A2ABaseModel

Defines a security scheme using OpenID Connect.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`open_id_connect_url` `instance-attribute` ¶

The OpenID Connect Discovery URL for the OIDC provider's metadata.

`type = 'openIdConnect'` `class-attribute` `instance-attribute` ¶

The type of the security scheme. Must be 'openIdConnect'.

`Part` ¶

Bases: RootModel[TextPart | FilePart | DataPart]

`root` `instance-attribute` ¶

A discriminated union representing a part of a message or artifact, which can be text, a file, or structured data.

`PartBase` ¶

Bases: A2ABaseModel

Defines base properties common to all message or artifact parts.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with this part.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`PasswordOAuthFlow` ¶

Bases: A2ABaseModel

Defines configuration details for the OAuth 2.0 Resource Owner Password flow.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`refresh_url = None` `class-attribute` `instance-attribute` ¶

The URL to be used for obtaining refresh tokens. This MUST be a URL.

`scopes` `instance-attribute` ¶

The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it.

`token_url` `instance-attribute` ¶

The token URL to be used for this flow. This MUST be a URL.

`PushNotificationAuthenticationInfo` ¶

Bases: A2ABaseModel

Defines authentication details for a push notification endpoint.

`credentials = None` `class-attribute` `instance-attribute` ¶

Optional credentials required by the push notification endpoint.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`schemes` `instance-attribute` ¶

A list of supported authentication schemes (e.g., 'Basic', 'Bearer').

`PushNotificationConfig` ¶

Bases: A2ABaseModel

Defines the configuration for setting up push notifications for task updates.

`authentication = None` `class-attribute` `instance-attribute` ¶

Optional authentication details for the agent to use when calling the notification URL.

`id = None` `class-attribute` `instance-attribute` ¶

A unique identifier (e.g. UUID) for the push notification configuration, set by the client to support multiple notification callbacks.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`token = None` `class-attribute` `instance-attribute` ¶

A unique token for this task or session to validate incoming push notifications.

`url` `instance-attribute` ¶

The callback URL where the agent should send push notifications.

`PushNotificationNotSupportedError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the agent does not support push notifications.

`code = -32003` `class-attribute` `instance-attribute` ¶

The error code for when push notifications are not supported.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Push Notification is not supported'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`Role` ¶

Bases: str, Enum

Identifies the sender of the message. user for the client, agent for the service.

`agent = 'agent'` `class-attribute` `instance-attribute` ¶

`user = 'user'` `class-attribute` `instance-attribute` ¶

`SecurityScheme` ¶

Bases: RootModel[APIKeySecurityScheme | HTTPAuthSecurityScheme | OAuth2SecurityScheme | OpenIdConnectSecurityScheme | MutualTLSSecurityScheme]

`root` `instance-attribute` ¶

Defines a security scheme that can be used to secure an agent's endpoints. This is a discriminated union type based on the OpenAPI 3.0 Security Scheme Object.

`SecuritySchemeBase` ¶

Bases: A2ABaseModel

Defines base properties shared by all security scheme objects.

`description = None` `class-attribute` `instance-attribute` ¶

An optional description for the security scheme.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`SendMessageRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the message/send method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'message/send'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'message/send'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters for sending a message.

`SendMessageResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | SendMessageSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the message/send method.

`SendMessageSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the message/send method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, which can be a direct reply Message or the initial Task object.

`SendStreamingMessageRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the message/stream method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'message/stream'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'message/stream'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters for sending a message.

`SendStreamingMessageResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | SendStreamingMessageSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the message/stream method.

`SendStreamingMessageSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the message/stream method. The server may send multiple response objects for a single request.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, which can be a Message, Task, or a streaming update event.

`SetTaskPushNotificationConfigRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/pushNotificationConfig/set method.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/pushNotificationConfig/set'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/pushNotificationConfig/set'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters for setting the push notification configuration.

`SetTaskPushNotificationConfigResponse` ¶

Bases: RootModel[JSONRPCErrorResponse | SetTaskPushNotificationConfigSuccessResponse]

`root` `instance-attribute` ¶

Represents a JSON-RPC response for the tasks/pushNotificationConfig/set method.

`SetTaskPushNotificationConfigSuccessResponse` ¶

Bases: A2ABaseModel

Represents a successful JSON-RPC response for the tasks/pushNotificationConfig/set method.

`id = None` `class-attribute` `instance-attribute` ¶

The identifier established by the client.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`result` `instance-attribute` ¶

The result, containing the configured push notification settings.

`Task` ¶

Bases: A2ABaseModel

Represents a single, stateful operation or conversation between a client and an agent.

`artifacts = None` `class-attribute` `instance-attribute` ¶

A collection of artifacts generated by the agent during the execution of the task.

`context_id` `instance-attribute` ¶

A server-generated unique identifier (e.g. UUID) for maintaining context across multiple related tasks or interactions.

`history = None` `class-attribute` `instance-attribute` ¶

An array of messages exchanged during the task, representing the conversation history.

`id` `instance-attribute` ¶

A unique identifier (e.g. UUID) for the task, generated by the server for a new task.

`kind = 'task'` `class-attribute` `instance-attribute` ¶

The type of this object, used as a discriminator. Always 'task' for a Task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions. The key is an extension-specific identifier.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`status` `instance-attribute` ¶

The current status of the task, including its state and a descriptive message.

`TaskArtifactUpdateEvent` ¶

Bases: A2ABaseModel

An event sent by the agent to notify the client that an artifact has been generated or updated. This is typically used in streaming models.

`append = None` `class-attribute` `instance-attribute` ¶

If true, the content of this artifact should be appended to a previously sent artifact with the same ID.

`artifact` `instance-attribute` ¶

The artifact that was generated or updated.

`context_id` `instance-attribute` ¶

The context ID associated with the task.

`kind = 'artifact-update'` `class-attribute` `instance-attribute` ¶

The type of this event, used as a discriminator. Always 'artifact-update'.

`last_chunk = None` `class-attribute` `instance-attribute` ¶

If true, this is the final chunk of the artifact.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`task_id` `instance-attribute` ¶

The ID of the task this artifact belongs to.

`TaskIdParams` ¶

Bases: A2ABaseModel

Defines parameters containing a task ID, used for simple task operations.

`id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with the request.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`TaskNotCancelableError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the task is in a state where it cannot be canceled.

`code = -32002` `class-attribute` `instance-attribute` ¶

The error code for a task that cannot be canceled.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Task cannot be canceled'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`TaskNotFoundError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the requested task ID was not found.

`code = -32001` `class-attribute` `instance-attribute` ¶

The error code for a task not found error.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'Task not found'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`TaskPushNotificationConfig` ¶

Bases: A2ABaseModel

A container associating a push notification configuration with a specific task.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notification_config` `instance-attribute` ¶

The push notification configuration for this task.

`task_id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`TaskQueryParams` ¶

Bases: A2ABaseModel

Defines parameters for querying a task, with an option to limit history length.

`history_length = None` `class-attribute` `instance-attribute` ¶

The number of most recent messages from the task's history to retrieve.

`id` `instance-attribute` ¶

The unique identifier (e.g. UUID) of the task.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with the request.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`TaskResubscriptionRequest` ¶

Bases: A2ABaseModel

Represents a JSON-RPC request for the tasks/resubscribe method, used to resume a streaming connection.

`id` `instance-attribute` ¶

The identifier for this request.

`jsonrpc = '2.0'` `class-attribute` `instance-attribute` ¶

The version of the JSON-RPC protocol. MUST be exactly "2.0".

`method = 'tasks/resubscribe'` `class-attribute` `instance-attribute` ¶

The method name. Must be 'tasks/resubscribe'.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`params` `instance-attribute` ¶

The parameters identifying the task to resubscribe to.

`TaskState` ¶

Bases: str, Enum

Defines the lifecycle states of a Task.

`auth_required = 'auth-required'` `class-attribute` `instance-attribute` ¶

`canceled = 'canceled'` `class-attribute` `instance-attribute` ¶

`completed = 'completed'` `class-attribute` `instance-attribute` ¶

`failed = 'failed'` `class-attribute` `instance-attribute` ¶

`input_required = 'input-required'` `class-attribute` `instance-attribute` ¶

`rejected = 'rejected'` `class-attribute` `instance-attribute` ¶

`submitted = 'submitted'` `class-attribute` `instance-attribute` ¶

`unknown = 'unknown'` `class-attribute` `instance-attribute` ¶

`working = 'working'` `class-attribute` `instance-attribute` ¶

`TaskStatus` ¶

Bases: A2ABaseModel

Represents the status of a task at a specific point in time.

`message = None` `class-attribute` `instance-attribute` ¶

An optional, human-readable message providing more details about the current status.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`state` `instance-attribute` ¶

The current state of the task's lifecycle.

`timestamp = Field(default=None, examples=['2023-10-27T10:00:00Z'])` `class-attribute` `instance-attribute` ¶

An ISO 8601 datetime string indicating when this status was recorded.

`TaskStatusUpdateEvent` ¶

Bases: A2ABaseModel

An event sent by the agent to notify the client of a change in a task's status. This is typically used in streaming or subscription models.

`context_id` `instance-attribute` ¶

The context ID associated with the task.

`final` `instance-attribute` ¶

If true, this is the final event in the stream for this interaction.

`kind = 'status-update'` `class-attribute` `instance-attribute` ¶

The type of this event, used as a discriminator. Always 'status-update'.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata for extensions.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`status` `instance-attribute` ¶

The new status of the task.

`task_id` `instance-attribute` ¶

The ID of the task that was updated.

`TextPart` ¶

Bases: A2ABaseModel

Represents a text segment within a message or artifact.

`kind = 'text'` `class-attribute` `instance-attribute` ¶

The type of this part, used as a discriminator. Always 'text'.

`metadata = None` `class-attribute` `instance-attribute` ¶

Optional metadata associated with this part.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`text` `instance-attribute` ¶

The string content of the text part.

`TransportProtocol` ¶

Bases: str, Enum

Supported A2A transport protocols.

`grpc = 'GRPC'` `class-attribute` `instance-attribute` ¶

`http_json = 'HTTP+JSON'` `class-attribute` `instance-attribute` ¶

`jsonrpc = 'JSONRPC'` `class-attribute` `instance-attribute` ¶

`UnsupportedOperationError` ¶

Bases: A2ABaseModel

An A2A-specific error indicating that the requested operation is not supported by the agent.

`code = -32004` `class-attribute` `instance-attribute` ¶

The error code for an unsupported operation.

`data = None` `class-attribute` `instance-attribute` ¶

A primitive or structured value containing additional information about the error. This may be omitted.

`message = 'This operation is not supported'` `class-attribute` `instance-attribute` ¶

The error message.

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

Python SDK Reference¶

Client¶

ClientEvent = tuple[Task, UpdateEvent] module-attribute ¶

Consumer = Callable[[ClientEvent | Message, AgentCard], Coroutine[None, Any, Any]] module-attribute ¶

logger = logging.getLogger(__name__) module-attribute ¶

A2ACardResolver ¶

agent_card_path = agent_card_path.lstrip('/') instance-attribute ¶

base_url = base_url.rstrip('/') instance-attribute ¶

httpx_client = httpx_client instance-attribute ¶

get_agent_card(relative_card_path=None, http_kwargs=None) async ¶

A2AClient ¶

cancel_task(request, *, http_kwargs=None, context=None) async ¶

get_card(*, http_kwargs=None, context=None) async ¶

get_task(request, *, http_kwargs=None, context=None) async ¶

get_task_callback(request, *, http_kwargs=None, context=None) async ¶

resubscribe(request, *, http_kwargs=None, context=None) async ¶

send_message(request, *, http_kwargs=None, context=None) async ¶

send_message_streaming(request, *, http_kwargs=None, context=None) async ¶

set_task_callback(request, *, http_kwargs=None, context=None) async ¶

A2AClientError ¶

A2AClientHTTPError ¶

message = message instance-attribute ¶

status_code = status_code instance-attribute ¶

A2AClientJSONError ¶

message = message instance-attribute ¶

A2AClientTimeoutError ¶

message = message instance-attribute ¶

A2AGrpcClient ¶

AuthInterceptor ¶

intercept(method_name, request_payload, http_kwargs, agent_card, context) async ¶

Client ¶

add_event_consumer(consumer) async ¶

add_request_middleware(middleware) async ¶

cancel_task(request, *, context=None) abstractmethod async ¶

consume(event, card) async ¶

get_card(*, context=None) abstractmethod async ¶

get_task(request, *, context=None) abstractmethod async ¶

get_task_callback(request, *, context=None) abstractmethod async ¶

resubscribe(request, *, context=None) abstractmethod async ¶

send_message(request, *, context=None) abstractmethod async ¶

set_task_callback(request, *, context=None) abstractmethod async ¶

ClientCallContext ¶

state = Field(default_factory=dict) class-attribute instance-attribute ¶

ClientCallInterceptor ¶

intercept(method_name, request_payload, http_kwargs, agent_card, context) abstractmethod async ¶

ClientConfig dataclass ¶

accepted_output_modes = dataclasses.field(default_factory=list) class-attribute instance-attribute ¶

grpc_channel_factory = None class-attribute instance-attribute ¶

httpx_client = None class-attribute instance-attribute ¶

polling = False class-attribute instance-attribute ¶

push_notification_configs = dataclasses.field(default_factory=list) class-attribute instance-attribute ¶

streaming = True class-attribute instance-attribute ¶

supported_transports = dataclasses.field(default_factory=list) class-attribute instance-attribute ¶

use_client_preference = False class-attribute instance-attribute ¶

ClientFactory ¶

Optionally register custom client implementations¶

Then with an agent card make a client with additional consumers and¶

interceptors¶

Now the client can be used the same regardless of transport and¶

aligns client config with server capabilities.¶

create(card, consumers=None, interceptors=None) ¶

register(label, generator) ¶

CredentialService ¶

get_credentials(security_scheme_name, context) abstractmethod async ¶

InMemoryContextCredentialStore ¶

get_credentials(security_scheme_name, context) async ¶

set_credentials(session_id, security_scheme_name, credential) async ¶

create_text_message_object(role=Role.user, content='') ¶

minimal_agent_card(url, transports=None) ¶

Server¶

Types¶

A2A ¶

root instance-attribute ¶

A2AError ¶

root instance-attribute ¶

A2ARequest ¶

root instance-attribute ¶

APIKeySecurityScheme ¶

description = None class-attribute instance-attribute ¶

in_ instance-attribute ¶

`ClientEvent = tuple[Task, UpdateEvent]` `module-attribute` ¶

`Consumer = Callable[[ClientEvent | Message, AgentCard], Coroutine[None, Any, Any]]` `module-attribute` ¶

`logger = logging.getLogger(name)` `module-attribute` ¶

`A2ACardResolver` ¶

`agent_card_path = agent_card_path.lstrip('/')` `instance-attribute` ¶

`base_url = base_url.rstrip('/')` `instance-attribute` ¶

`httpx_client = httpx_client` `instance-attribute` ¶

`get_agent_card(relative_card_path=None, http_kwargs=None)` `async` ¶

`A2AClient` ¶

`cancel_task(request, *, http_kwargs=None, context=None)` `async` ¶

`get_card(*, http_kwargs=None, context=None)` `async` ¶

`get_task(request, *, http_kwargs=None, context=None)` `async` ¶

`get_task_callback(request, *, http_kwargs=None, context=None)` `async` ¶

`resubscribe(request, *, http_kwargs=None, context=None)` `async` ¶

`send_message(request, *, http_kwargs=None, context=None)` `async` ¶

`send_message_streaming(request, *, http_kwargs=None, context=None)` `async` ¶

`set_task_callback(request, *, http_kwargs=None, context=None)` `async` ¶

`A2AClientError` ¶

`A2AClientHTTPError` ¶

`message = message` `instance-attribute` ¶

`status_code = status_code` `instance-attribute` ¶

`A2AClientJSONError` ¶

`message = message` `instance-attribute` ¶

`A2AClientTimeoutError` ¶

`message = message` `instance-attribute` ¶

`A2AGrpcClient` ¶

`AuthInterceptor` ¶

`intercept(method_name, request_payload, http_kwargs, agent_card, context)` `async` ¶

`Client` ¶

`add_event_consumer(consumer)` `async` ¶

`add_request_middleware(middleware)` `async` ¶

`cancel_task(request, *, context=None)` `abstractmethod` `async` ¶

`consume(event, card)` `async` ¶

`get_card(*, context=None)` `abstractmethod` `async` ¶

`get_task(request, *, context=None)` `abstractmethod` `async` ¶

`get_task_callback(request, *, context=None)` `abstractmethod` `async` ¶

`resubscribe(request, *, context=None)` `abstractmethod` `async` ¶

`send_message(request, *, context=None)` `abstractmethod` `async` ¶

`set_task_callback(request, *, context=None)` `abstractmethod` `async` ¶

`ClientCallContext` ¶

`state = Field(default_factory=dict)` `class-attribute` `instance-attribute` ¶

`ClientCallInterceptor` ¶

`intercept(method_name, request_payload, http_kwargs, agent_card, context)` `abstractmethod` `async` ¶

`ClientConfig` `dataclass` ¶

`accepted_output_modes = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

`grpc_channel_factory = None` `class-attribute` `instance-attribute` ¶

`httpx_client = None` `class-attribute` `instance-attribute` ¶

`polling = False` `class-attribute` `instance-attribute` ¶

`push_notification_configs = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

`streaming = True` `class-attribute` `instance-attribute` ¶

`supported_transports = dataclasses.field(default_factory=list)` `class-attribute` `instance-attribute` ¶

`use_client_preference = False` `class-attribute` `instance-attribute` ¶

`ClientFactory` ¶

`create(card, consumers=None, interceptors=None)` ¶

`register(label, generator)` ¶

`CredentialService` ¶

`get_credentials(security_scheme_name, context)` `abstractmethod` `async` ¶

`InMemoryContextCredentialStore` ¶

`get_credentials(security_scheme_name, context)` `async` ¶

`set_credentials(session_id, security_scheme_name, credential)` `async` ¶

`create_text_message_object(role=Role.user, content='')` ¶

`minimal_agent_card(url, transports=None)` ¶

`A2A` ¶

`root` `instance-attribute` ¶

`A2AError` ¶

`root` `instance-attribute` ¶

`A2ARequest` ¶

`root` `instance-attribute` ¶

`APIKeySecurityScheme` ¶

`description = None` `class-attribute` `instance-attribute` ¶

`in_` `instance-attribute` ¶

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`name` `instance-attribute` ¶

`type = 'apiKey'` `class-attribute` `instance-attribute` ¶

`AgentCapabilities` ¶

`extensions = None` `class-attribute` `instance-attribute` ¶

`model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, serialize_by_alias=True, alias_generator=to_camel_custom)` `class-attribute` `instance-attribute` ¶

`push_notifications = None` `class-attribute` `instance-attribute` ¶

`state_transition_history = None` `class-attribute` `instance-attribute` ¶

`streaming = None` `class-attribute` `instance-attribute` ¶