Package org.a2aproject.sdk.spec

Class A2AError

java.lang.Object

java.lang.Throwable

java.lang.Exception

java.lang.RuntimeException

org.a2aproject.sdk.spec.A2AError

All Implemented Interfaces:

Serializable, Event

Direct Known Subclasses:

A2AProtocolError, InternalError, InvalidParamsError, InvalidRequestError, JSONParseError, MethodNotFoundError

public class A2AError
extends RuntimeException
implements Event

Marker interface for A2A Protocol error events.

This interface extends Event to allow errors to be transmitted as events in the A2A Protocol's event stream. All protocol-level errors implement this interface, enabling uniform error handling across both streaming and non-streaming communication.

A2A errors typically extend A2AError to provide JSON-RPC 2.0 compliant error responses with standard error codes, messages, and optional additional data.

Common implementations include:

• InvalidParamsError - Invalid method parameters
• InvalidRequestError - Malformed request
• MethodNotFoundError - Unknown method
• InternalError - Server-side error
• TaskNotFoundError - Task does not exist
• And others for specific protocol error conditions

See Also:

• for the base event interface
• for the base error implementation
• JSON-RPC 2.0 Error Object
• A2A Protocol Specification
• Serialized Form

Constructor Summary

Constructors

Constructor	Description
A2AError(Integer code, String message, @Nullable Map<String,Object> details)	Constructs a JSON-RPC error with the specified code, message, and optional details.

Method Summary

Modifier and Type	Method	Description
Integer	getCode()	Gets the numeric error code indicating the error type.
Map<String,Object>	getDetails()	Gets additional details about the error as key-value pairs.

Methods inherited from class java.lang.Throwable

addSuppressed, fillInStackTrace, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

A2AError

public A2AError(Integer code,
 String message,
 @Nullable Map<String,Object> details)

Constructs a JSON-RPC error with the specified code, message, and optional details.

This constructor is used by Jackson for JSON deserialization.

Parameters:

code - the numeric error code (required, see JSON-RPC 2.0 spec for standard codes)

message - the human-readable error message (required)

details - additional error details as key-value pairs (defaults to empty map if null)

Throws:

IllegalArgumentException - if code or message is null

Method Details

getCode

public Integer getCode()

Gets the numeric error code indicating the error type.

Standard JSON-RPC 2.0 error codes:

• -32700: Parse error
• -32600: Invalid Request
• -32601: Method not found
• -32602: Invalid params
• -32603: Internal error
• -32000 to -32099: Server error (implementation-defined)

Returns:

the error code

getDetails

public Map<String,Object> getDetails()

Gets additional details about the error as key-value pairs.

Returns:

the error details, never null (empty map if no details provided)