$schema: http://json-schema.org/draft-07/schema# definitions: A2AError: anyOf: - $ref: '#/definitions/JSONParseError' - $ref: '#/definitions/InvalidRequestError' - $ref: '#/definitions/MethodNotFoundError' - $ref: '#/definitions/InvalidParamsError' - $ref: '#/definitions/InternalError' - $ref: '#/definitions/TaskNotFoundError' - $ref: '#/definitions/TaskNotCancelableError' - $ref: '#/definitions/PushNotificationNotSupportedError' - $ref: '#/definitions/UnsupportedOperationError' - $ref: '#/definitions/ContentTypeNotSupportedError' - $ref: '#/definitions/InvalidAgentResponseError' - $ref: '#/definitions/AuthenticatedExtendedCardNotConfiguredError' description: A discriminated union of all standard JSON-RPC and A2A-specific error types. A2ARequest: anyOf: - $ref: '#/definitions/SendMessageRequest' - $ref: '#/definitions/SendStreamingMessageRequest' - $ref: '#/definitions/GetTaskRequest' - $ref: '#/definitions/CancelTaskRequest' - $ref: '#/definitions/SetTaskPushNotificationConfigRequest' - $ref: '#/definitions/GetTaskPushNotificationConfigRequest' - $ref: '#/definitions/TaskResubscriptionRequest' - $ref: '#/definitions/ListTaskPushNotificationConfigRequest' - $ref: '#/definitions/DeleteTaskPushNotificationConfigRequest' - $ref: '#/definitions/GetAuthenticatedExtendedCardRequest' description: A discriminated union representing all possible JSON-RPC 2.0 requests supported by the A2A specification. APIKeySecurityScheme: description: Defines a security scheme using an API key. properties: description: description: An optional description for the security scheme. type: string in: description: The location of the API key. enum: - cookie - header - query type: string name: description: The name of the header, query, or cookie parameter to be used. type: string type: const: apiKey description: The type of the security scheme. Must be 'apiKey'. type: string required: - in - name - type type: object AgentCapabilities: description: Defines optional capabilities supported by an agent. properties: extensions: description: A list of protocol extensions supported by the agent. items: $ref: '#/definitions/AgentExtension' type: array pushNotifications: description: Indicates if the agent supports sending push notifications for asynchronous task updates. type: boolean stateTransitionHistory: description: Indicates if the agent provides a history of state transitions for a task. type: boolean streaming: description: Indicates if the agent supports Server-Sent Events (SSE) for streaming responses. type: boolean type: object AgentCard: description: |- 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. properties: additionalInterfaces: description: |- 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. items: $ref: '#/definitions/AgentInterface' type: array capabilities: $ref: '#/definitions/AgentCapabilities' description: A declaration of optional capabilities supported by the agent. defaultInputModes: description: |- Default set of supported input MIME types for all skills, which can be overridden on a per-skill basis. items: type: string type: array defaultOutputModes: description: |- Default set of supported output MIME types for all skills, which can be overridden on a per-skill basis. items: type: string type: array description: description: |- A human-readable description of the agent, assisting users and other agents in understanding its purpose. examples: - Agent that helps users with recipes and cooking. type: string documentationUrl: description: An optional URL to the agent's documentation. type: string iconUrl: description: An optional URL to an icon for the agent. type: string name: description: A human-readable name for the agent. examples: - Recipe Agent type: string preferredTransport: default: JSONRPC description: |- 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. examples: - JSONRPC - GRPC - HTTP+JSON type: string protocolVersion: default: 0.3.0 description: The version of the A2A protocol this agent supports. type: string provider: $ref: '#/definitions/AgentProvider' description: Information about the agent's service provider. security: description: |- 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." examples: - - oauth: - read - api-key: [] mtls: [] items: additionalProperties: items: type: string type: array type: object type: array securitySchemes: additionalProperties: $ref: '#/definitions/SecurityScheme' description: |- A declaration of the security schemes available to authorize requests. The key is the scheme name. Follows the OpenAPI 3.0 Security Scheme Object. type: object signatures: description: JSON Web Signatures computed for this AgentCard. items: $ref: '#/definitions/AgentCardSignature' type: array skills: description: The set of skills, or distinct capabilities, that the agent can perform. items: $ref: '#/definitions/AgentSkill' type: array supportsAuthenticatedExtendedCard: description: |- If true, the agent can provide an extended agent card with additional details to authenticated users. Defaults to false. type: boolean url: description: |- The preferred endpoint URL for interacting with the agent. This URL MUST support the transport specified by 'preferredTransport'. examples: - https://api.example.com/a2a/v1 type: string version: description: The agent's own version number. The format is defined by the provider. examples: - 1.0.0 type: string required: - capabilities - defaultInputModes - defaultOutputModes - description - name - protocolVersion - skills - url - version type: object AgentCardSignature: description: |- AgentCardSignature represents a JWS signature of an AgentCard. This follows the JSON format of an RFC 7515 JSON Web Signature (JWS). properties: header: additionalProperties: {} description: The unprotected JWS header values. type: object protected: description: |- The protected JWS header for the signature. This is a Base64url-encoded JSON object, as per RFC 7515. type: string signature: description: The computed signature, Base64url-encoded. type: string required: - protected - signature type: object AgentExtension: description: A declaration of a protocol extension supported by an Agent. examples: - description: Google OAuth 2.0 authentication required: false uri: https://developers.google.com/identity/protocols/oauth2 properties: description: description: A human-readable description of how this agent uses the extension. type: string params: additionalProperties: {} description: Optional, extension-specific configuration parameters. type: object required: description: |- If true, the client must understand and comply with the extension's requirements to interact with the agent. type: boolean uri: description: The unique URI identifying the extension. type: string required: - uri type: object AgentInterface: description: |- 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. properties: transport: description: The transport protocol supported at this URL. examples: - JSONRPC - GRPC - HTTP+JSON type: string url: description: The URL where this interface is available. Must be a valid absolute HTTPS URL in production. examples: - https://api.example.com/a2a/v1 - https://grpc.example.com/a2a - https://rest.example.com/v1 type: string required: - transport - url type: object AgentProvider: description: Represents the service provider of an agent. examples: - organization: Google url: https://ai.google.dev properties: organization: description: The name of the agent provider's organization. type: string url: description: A URL for the agent provider's website or relevant documentation. type: string required: - organization - url type: object AgentSkill: description: Represents a distinct capability or function that an agent can perform. properties: description: description: |- A detailed description of the skill, intended to help clients or users understand its purpose and functionality. type: string examples: description: |- Example prompts or scenarios that this skill can handle. Provides a hint to the client on how to use the skill. examples: - - I need a recipe for bread items: type: string type: array id: description: A unique identifier for the agent's skill. type: string inputModes: description: The set of supported input MIME types for this skill, overriding the agent's defaults. items: type: string type: array name: description: A human-readable name for the skill. type: string outputModes: description: The set of supported output MIME types for this skill, overriding the agent's defaults. items: type: string type: array security: description: |- 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). examples: - - google: - oidc items: additionalProperties: items: type: string type: array type: object type: array tags: description: A set of keywords describing the skill's capabilities. examples: - - cooking - customer support - billing items: type: string type: array required: - description - id - name - tags type: object Artifact: description: Represents a file, data structure, or other resource generated by an agent during a task. properties: artifactId: description: A unique identifier (e.g. UUID) for the artifact within the scope of the task. type: string description: description: An optional, human-readable description of the artifact. type: string extensions: description: The URIs of extensions that are relevant to this artifact. items: type: string type: array metadata: additionalProperties: {} description: Optional metadata for extensions. The key is an extension-specific identifier. type: object name: description: An optional, human-readable name for the artifact. type: string parts: description: An array of content parts that make up the artifact. items: $ref: '#/definitions/Part' type: array required: - artifactId - parts type: object AuthenticatedExtendedCardNotConfiguredError: description: An A2A-specific error indicating that the agent does not have an Authenticated Extended Card configured properties: code: const: -32007 description: The error code for when an authenticated extended card is not configured. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Authenticated Extended Card is not configured description: The error message. type: string required: - code - message type: object AuthorizationCodeOAuthFlow: description: Defines configuration details for the OAuth 2.0 Authorization Code flow. properties: authorizationUrl: description: |- The authorization URL to be used for this flow. This MUST be a URL and use TLS. type: string refreshUrl: description: |- The URL to be used for obtaining refresh tokens. This MUST be a URL and use TLS. type: string scopes: additionalProperties: type: string description: |- The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it. type: object tokenUrl: description: |- The token URL to be used for this flow. This MUST be a URL and use TLS. type: string required: - authorizationUrl - scopes - tokenUrl type: object CancelTaskRequest: description: Represents a JSON-RPC request for the `tasks/cancel` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/cancel description: The method name. Must be 'tasks/cancel'. type: string params: $ref: '#/definitions/TaskIdParams' description: The parameters identifying the task to cancel. required: - id - jsonrpc - method - params type: object CancelTaskResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/CancelTaskSuccessResponse' description: Represents a JSON-RPC response for the `tasks/cancel` method. CancelTaskSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/cancel` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: $ref: '#/definitions/Task' description: The result, containing the final state of the canceled Task object. required: - id - jsonrpc - result type: object ClientCredentialsOAuthFlow: description: Defines configuration details for the OAuth 2.0 Client Credentials flow. properties: refreshUrl: description: The URL to be used for obtaining refresh tokens. This MUST be a URL. type: string scopes: additionalProperties: type: string description: |- The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it. type: object tokenUrl: description: The token URL to be used for this flow. This MUST be a URL. type: string required: - scopes - tokenUrl type: object ContentTypeNotSupportedError: description: |- An A2A-specific error indicating an incompatibility between the requested content types and the agent's capabilities. properties: code: const: -32005 description: The error code for an unsupported content type. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Incompatible content types description: The error message. type: string required: - code - message type: object DataPart: description: Represents a structured data segment (e.g., JSON) within a message or artifact. properties: data: additionalProperties: {} description: The structured data content. type: object kind: const: data description: The type of this part, used as a discriminator. Always 'data'. type: string metadata: additionalProperties: {} description: Optional metadata associated with this part. type: object required: - data - kind type: object DeleteTaskPushNotificationConfigParams: description: Defines parameters for deleting a specific push notification configuration for a task. properties: id: description: The unique identifier (e.g. UUID) of the task. type: string metadata: additionalProperties: {} description: Optional metadata associated with the request. type: object pushNotificationConfigId: description: The ID of the push notification configuration to delete. type: string required: - id - pushNotificationConfigId type: object DeleteTaskPushNotificationConfigRequest: description: Represents a JSON-RPC request for the `tasks/pushNotificationConfig/delete` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/pushNotificationConfig/delete description: The method name. Must be 'tasks/pushNotificationConfig/delete'. type: string params: $ref: '#/definitions/DeleteTaskPushNotificationConfigParams' description: The parameters identifying the push notification configuration to delete. required: - id - jsonrpc - method - params type: object DeleteTaskPushNotificationConfigResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/DeleteTaskPushNotificationConfigSuccessResponse' description: Represents a JSON-RPC response for the `tasks/pushNotificationConfig/delete` method. DeleteTaskPushNotificationConfigSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/pushNotificationConfig/delete` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: description: The result is null on successful deletion. type: 'null' required: - id - jsonrpc - result type: object FileBase: description: Defines base properties for a file. properties: mimeType: description: The MIME type of the file (e.g., "application/pdf"). type: string name: description: An optional name for the file (e.g., "document.pdf"). type: string type: object FilePart: description: |- Represents a file segment within a message or artifact. The file content can be provided either directly as bytes or as a URI. properties: file: anyOf: - $ref: '#/definitions/FileWithBytes' - $ref: '#/definitions/FileWithUri' description: The file content, represented as either a URI or as base64-encoded bytes. kind: const: file description: The type of this part, used as a discriminator. Always 'file'. type: string metadata: additionalProperties: {} description: Optional metadata associated with this part. type: object required: - file - kind type: object FileWithBytes: description: Represents a file with its content provided directly as a base64-encoded string. properties: bytes: description: The base64-encoded content of the file. type: string mimeType: description: The MIME type of the file (e.g., "application/pdf"). type: string name: description: An optional name for the file (e.g., "document.pdf"). type: string required: - bytes type: object FileWithUri: description: Represents a file with its content located at a specific URI. properties: mimeType: description: The MIME type of the file (e.g., "application/pdf"). type: string name: description: An optional name for the file (e.g., "document.pdf"). type: string uri: description: A URL pointing to the file's content. type: string required: - uri type: object GetAuthenticatedExtendedCardRequest: description: Represents a JSON-RPC request for the `agent/getAuthenticatedExtendedCard` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: agent/getAuthenticatedExtendedCard description: The method name. Must be 'agent/getAuthenticatedExtendedCard'. type: string required: - id - jsonrpc - method type: object GetAuthenticatedExtendedCardResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/GetAuthenticatedExtendedCardSuccessResponse' description: Represents a JSON-RPC response for the `agent/getAuthenticatedExtendedCard` method. GetAuthenticatedExtendedCardSuccessResponse: description: Represents a successful JSON-RPC response for the `agent/getAuthenticatedExtendedCard` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: $ref: '#/definitions/AgentCard' description: The result is an Agent Card object. required: - id - jsonrpc - result type: object GetTaskPushNotificationConfigParams: description: Defines parameters for fetching a specific push notification configuration for a task. properties: id: description: The unique identifier (e.g. UUID) of the task. type: string metadata: additionalProperties: {} description: Optional metadata associated with the request. type: object pushNotificationConfigId: description: The ID of the push notification configuration to retrieve. type: string required: - id type: object GetTaskPushNotificationConfigRequest: description: Represents a JSON-RPC request for the `tasks/pushNotificationConfig/get` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/pushNotificationConfig/get description: The method name. Must be 'tasks/pushNotificationConfig/get'. type: string params: anyOf: - $ref: '#/definitions/TaskIdParams' - $ref: '#/definitions/GetTaskPushNotificationConfigParams' description: The parameters for getting a push notification configuration. required: - id - jsonrpc - method - params type: object GetTaskPushNotificationConfigResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/GetTaskPushNotificationConfigSuccessResponse' description: Represents a JSON-RPC response for the `tasks/pushNotificationConfig/get` method. GetTaskPushNotificationConfigSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/pushNotificationConfig/get` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: $ref: '#/definitions/TaskPushNotificationConfig' description: The result, containing the requested push notification configuration. required: - id - jsonrpc - result type: object GetTaskRequest: description: Represents a JSON-RPC request for the `tasks/get` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/get description: The method name. Must be 'tasks/get'. type: string params: $ref: '#/definitions/TaskQueryParams' description: The parameters for querying a task. required: - id - jsonrpc - method - params type: object GetTaskResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/GetTaskSuccessResponse' description: Represents a JSON-RPC response for the `tasks/get` method. GetTaskSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/get` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: $ref: '#/definitions/Task' description: The result, containing the requested Task object. required: - id - jsonrpc - result type: object HTTPAuthSecurityScheme: description: Defines a security scheme using HTTP authentication. properties: bearerFormat: description: |- A hint to the client to identify how the bearer token is formatted (e.g., "JWT"). This is primarily for documentation purposes. type: string description: description: An optional description for the security scheme. type: string scheme: description: |- 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: string type: const: http description: The type of the security scheme. Must be 'http'. type: string required: - scheme - type type: object ImplicitOAuthFlow: description: Defines configuration details for the OAuth 2.0 Implicit flow. properties: authorizationUrl: description: The authorization URL to be used for this flow. This MUST be a URL. type: string refreshUrl: description: The URL to be used for obtaining refresh tokens. This MUST be a URL. type: string scopes: additionalProperties: type: string description: |- The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it. type: object required: - authorizationUrl - scopes type: object InternalError: description: An error indicating an internal error on the server. properties: code: const: -32603 description: The error code for an internal server error. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Internal error description: The error message. type: string required: - code - message type: object InvalidAgentResponseError: description: |- An A2A-specific error indicating that the agent returned a response that does not conform to the specification for the current method. properties: code: const: -32006 description: The error code for an invalid agent response. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Invalid agent response description: The error message. type: string required: - code - message type: object InvalidParamsError: description: An error indicating that the method parameters are invalid. properties: code: const: -32602 description: The error code for an invalid parameters error. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Invalid parameters description: The error message. type: string required: - code - message type: object InvalidRequestError: description: An error indicating that the JSON sent is not a valid Request object. properties: code: const: -32600 description: The error code for an invalid request. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Request payload validation error description: The error message. type: string required: - code - message type: object JSONParseError: description: An error indicating that the server received invalid JSON. properties: code: const: -32700 description: The error code for a JSON parse error. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Invalid JSON payload description: The error message. type: string required: - code - message type: object JSONRPCError: description: Represents a JSON-RPC 2.0 Error object, included in an error response. properties: code: description: A number that indicates the error type that occurred. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: description: A string providing a short description of the error. type: string required: - code - message type: object JSONRPCErrorResponse: description: Represents a JSON-RPC 2.0 Error Response object. properties: error: anyOf: - $ref: '#/definitions/JSONRPCError' - $ref: '#/definitions/JSONParseError' - $ref: '#/definitions/InvalidRequestError' - $ref: '#/definitions/MethodNotFoundError' - $ref: '#/definitions/InvalidParamsError' - $ref: '#/definitions/InternalError' - $ref: '#/definitions/TaskNotFoundError' - $ref: '#/definitions/TaskNotCancelableError' - $ref: '#/definitions/PushNotificationNotSupportedError' - $ref: '#/definitions/UnsupportedOperationError' - $ref: '#/definitions/ContentTypeNotSupportedError' - $ref: '#/definitions/InvalidAgentResponseError' - $ref: '#/definitions/AuthenticatedExtendedCardNotConfiguredError' description: An object describing the error that occurred. id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string required: - error - id - jsonrpc type: object JSONRPCMessage: description: Defines the base structure for any JSON-RPC 2.0 request, response, or notification. properties: id: description: |- 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. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string required: - jsonrpc type: object JSONRPCRequest: description: Represents a JSON-RPC 2.0 Request object. properties: id: description: |- 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. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: description: A string containing the name of the method to be invoked. type: string params: additionalProperties: {} description: A structured value holding the parameter values to be used during the method invocation. type: object required: - jsonrpc - method type: object JSONRPCResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/SendMessageSuccessResponse' - $ref: '#/definitions/SendStreamingMessageSuccessResponse' - $ref: '#/definitions/GetTaskSuccessResponse' - $ref: '#/definitions/CancelTaskSuccessResponse' - $ref: '#/definitions/SetTaskPushNotificationConfigSuccessResponse' - $ref: '#/definitions/GetTaskPushNotificationConfigSuccessResponse' - $ref: '#/definitions/ListTaskPushNotificationConfigSuccessResponse' - $ref: '#/definitions/DeleteTaskPushNotificationConfigSuccessResponse' - $ref: '#/definitions/GetAuthenticatedExtendedCardSuccessResponse' description: |- A discriminated union representing all possible JSON-RPC 2.0 responses for the A2A specification methods. JSONRPCSuccessResponse: description: Represents a successful JSON-RPC 2.0 Response object. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: description: The value of this member is determined by the method invoked on the Server. required: - id - jsonrpc - result type: object ListTaskPushNotificationConfigParams: description: Defines parameters for listing all push notification configurations associated with a task. properties: id: description: The unique identifier (e.g. UUID) of the task. type: string metadata: additionalProperties: {} description: Optional metadata associated with the request. type: object required: - id type: object ListTaskPushNotificationConfigRequest: description: Represents a JSON-RPC request for the `tasks/pushNotificationConfig/list` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/pushNotificationConfig/list description: The method name. Must be 'tasks/pushNotificationConfig/list'. type: string params: $ref: '#/definitions/ListTaskPushNotificationConfigParams' description: The parameters identifying the task whose configurations are to be listed. required: - id - jsonrpc - method - params type: object ListTaskPushNotificationConfigResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/ListTaskPushNotificationConfigSuccessResponse' description: Represents a JSON-RPC response for the `tasks/pushNotificationConfig/list` method. ListTaskPushNotificationConfigSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/pushNotificationConfig/list` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: description: The result, containing an array of all push notification configurations for the task. items: $ref: '#/definitions/TaskPushNotificationConfig' type: array required: - id - jsonrpc - result type: object Message: description: Represents a single message in the conversation between a user and an agent. properties: contextId: description: The context ID for this message, used to group related interactions. type: string extensions: description: The URIs of extensions that are relevant to this message. items: type: string type: array kind: const: message description: The type of this object, used as a discriminator. Always 'message' for a Message. type: string messageId: description: A unique identifier for the message, typically a UUID, generated by the sender. type: string metadata: additionalProperties: {} description: Optional metadata for extensions. The key is an extension-specific identifier. type: object parts: description: |- 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). items: $ref: '#/definitions/Part' type: array referenceTaskIds: description: A list of other task IDs that this message references for additional context. items: type: string type: array role: description: Identifies the sender of the message. `user` for the client, `agent` for the service. enum: - agent - user type: string taskId: description: The ID of the task this message is part of. Can be omitted for the first message of a new task. type: string required: - kind - messageId - parts - role type: object MessageSendConfiguration: description: Defines configuration options for a `message/send` or `message/stream` request. properties: acceptedOutputModes: description: A list of output MIME types the client is prepared to accept in the response. items: type: string type: array blocking: description: If true, the client will wait for the task to complete. The server may reject this if the task is long-running. type: boolean historyLength: description: The number of most recent messages from the task's history to retrieve in the response. type: integer pushNotificationConfig: $ref: '#/definitions/PushNotificationConfig' description: Configuration for the agent to send push notifications for updates after the initial response. type: object MessageSendParams: description: |- 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. properties: configuration: $ref: '#/definitions/MessageSendConfiguration' description: Optional configuration for the send request. message: $ref: '#/definitions/Message' description: The message object being sent to the agent. metadata: additionalProperties: {} description: Optional metadata for extensions. type: object required: - message type: object MethodNotFoundError: description: An error indicating that the requested method does not exist or is not available. properties: code: const: -32601 description: The error code for a method not found error. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Method not found description: The error message. type: string required: - code - message type: object MutualTLSSecurityScheme: description: Defines a security scheme using mTLS authentication. properties: description: description: An optional description for the security scheme. type: string type: const: mutualTLS description: The type of the security scheme. Must be 'mutualTLS'. type: string required: - type type: object OAuth2SecurityScheme: description: Defines a security scheme using OAuth 2.0. properties: description: description: An optional description for the security scheme. type: string flows: $ref: '#/definitions/OAuthFlows' description: An object containing configuration information for the supported OAuth 2.0 flows. oauth2MetadataUrl: description: |- URL to the oauth2 authorization server metadata [RFC8414](https://datatracker.ietf.org/doc/html/rfc8414). TLS is required. type: string type: const: oauth2 description: The type of the security scheme. Must be 'oauth2'. type: string required: - flows - type type: object OAuthFlows: description: Defines the configuration for the supported OAuth 2.0 flows. properties: authorizationCode: $ref: '#/definitions/AuthorizationCodeOAuthFlow' description: Configuration for the OAuth Authorization Code flow. Previously called accessCode in OpenAPI 2.0. clientCredentials: $ref: '#/definitions/ClientCredentialsOAuthFlow' description: Configuration for the OAuth Client Credentials flow. Previously called application in OpenAPI 2.0. implicit: $ref: '#/definitions/ImplicitOAuthFlow' description: Configuration for the OAuth Implicit flow. password: $ref: '#/definitions/PasswordOAuthFlow' description: Configuration for the OAuth Resource Owner Password flow. type: object OpenIdConnectSecurityScheme: description: Defines a security scheme using OpenID Connect. properties: description: description: An optional description for the security scheme. type: string openIdConnectUrl: description: The OpenID Connect Discovery URL for the OIDC provider's metadata. type: string type: const: openIdConnect description: The type of the security scheme. Must be 'openIdConnect'. type: string required: - openIdConnectUrl - type type: object Part: anyOf: - $ref: '#/definitions/TextPart' - $ref: '#/definitions/FilePart' - $ref: '#/definitions/DataPart' description: |- A discriminated union representing a part of a message or artifact, which can be text, a file, or structured data. PartBase: description: Defines base properties common to all message or artifact parts. properties: metadata: additionalProperties: {} description: Optional metadata associated with this part. type: object type: object PasswordOAuthFlow: description: Defines configuration details for the OAuth 2.0 Resource Owner Password flow. properties: refreshUrl: description: The URL to be used for obtaining refresh tokens. This MUST be a URL. type: string scopes: additionalProperties: type: string description: |- The available scopes for the OAuth2 security scheme. A map between the scope name and a short description for it. type: object tokenUrl: description: The token URL to be used for this flow. This MUST be a URL. type: string required: - scopes - tokenUrl type: object PushNotificationAuthenticationInfo: description: Defines authentication details for a push notification endpoint. properties: credentials: description: Optional credentials required by the push notification endpoint. type: string schemes: description: A list of supported authentication schemes (e.g., 'Basic', 'Bearer'). items: type: string type: array required: - schemes type: object PushNotificationConfig: description: Defines the configuration for setting up push notifications for task updates. properties: authentication: $ref: '#/definitions/PushNotificationAuthenticationInfo' description: Optional authentication details for the agent to use when calling the notification URL. id: description: |- A unique identifier (e.g. UUID) for the push notification configuration, set by the client to support multiple notification callbacks. type: string token: description: A unique token for this task or session to validate incoming push notifications. type: string url: description: The callback URL where the agent should send push notifications. type: string required: - url type: object PushNotificationNotSupportedError: description: An A2A-specific error indicating that the agent does not support push notifications. properties: code: const: -32003 description: The error code for when push notifications are not supported. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Push Notification is not supported description: The error message. type: string required: - code - message type: object SecurityScheme: anyOf: - $ref: '#/definitions/APIKeySecurityScheme' - $ref: '#/definitions/HTTPAuthSecurityScheme' - $ref: '#/definitions/OAuth2SecurityScheme' - $ref: '#/definitions/OpenIdConnectSecurityScheme' - $ref: '#/definitions/MutualTLSSecurityScheme' description: |- 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: description: Defines base properties shared by all security scheme objects. properties: description: description: An optional description for the security scheme. type: string type: object SendMessageRequest: description: Represents a JSON-RPC request for the `message/send` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: message/send description: The method name. Must be 'message/send'. type: string params: $ref: '#/definitions/MessageSendParams' description: The parameters for sending a message. required: - id - jsonrpc - method - params type: object SendMessageResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/SendMessageSuccessResponse' description: Represents a JSON-RPC response for the `message/send` method. SendMessageSuccessResponse: description: Represents a successful JSON-RPC response for the `message/send` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: anyOf: - $ref: '#/definitions/Task' - $ref: '#/definitions/Message' description: The result, which can be a direct reply Message or the initial Task object. required: - id - jsonrpc - result type: object SendStreamingMessageRequest: description: Represents a JSON-RPC request for the `message/stream` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: message/stream description: The method name. Must be 'message/stream'. type: string params: $ref: '#/definitions/MessageSendParams' description: The parameters for sending a message. required: - id - jsonrpc - method - params type: object SendStreamingMessageResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/SendStreamingMessageSuccessResponse' description: Represents a JSON-RPC response for the `message/stream` method. SendStreamingMessageSuccessResponse: description: |- Represents a successful JSON-RPC response for the `message/stream` method. The server may send multiple response objects for a single request. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: anyOf: - $ref: '#/definitions/Task' - $ref: '#/definitions/Message' - $ref: '#/definitions/TaskStatusUpdateEvent' - $ref: '#/definitions/TaskArtifactUpdateEvent' description: The result, which can be a Message, Task, or a streaming update event. required: - id - jsonrpc - result type: object SetTaskPushNotificationConfigRequest: description: Represents a JSON-RPC request for the `tasks/pushNotificationConfig/set` method. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/pushNotificationConfig/set description: The method name. Must be 'tasks/pushNotificationConfig/set'. type: string params: $ref: '#/definitions/TaskPushNotificationConfig' description: The parameters for setting the push notification configuration. required: - id - jsonrpc - method - params type: object SetTaskPushNotificationConfigResponse: anyOf: - $ref: '#/definitions/JSONRPCErrorResponse' - $ref: '#/definitions/SetTaskPushNotificationConfigSuccessResponse' description: Represents a JSON-RPC response for the `tasks/pushNotificationConfig/set` method. SetTaskPushNotificationConfigSuccessResponse: description: Represents a successful JSON-RPC response for the `tasks/pushNotificationConfig/set` method. properties: id: description: The identifier established by the client. type: - string - integer - 'null' jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string result: $ref: '#/definitions/TaskPushNotificationConfig' description: The result, containing the configured push notification settings. required: - id - jsonrpc - result type: object Task: description: Represents a single, stateful operation or conversation between a client and an agent. properties: artifacts: description: A collection of artifacts generated by the agent during the execution of the task. items: $ref: '#/definitions/Artifact' type: array contextId: description: A server-generated unique identifier (e.g. UUID) for maintaining context across multiple related tasks or interactions. type: string history: description: An array of messages exchanged during the task, representing the conversation history. items: $ref: '#/definitions/Message' type: array id: description: A unique identifier (e.g. UUID) for the task, generated by the server for a new task. type: string kind: const: task description: The type of this object, used as a discriminator. Always 'task' for a Task. type: string metadata: additionalProperties: {} description: Optional metadata for extensions. The key is an extension-specific identifier. type: object status: $ref: '#/definitions/TaskStatus' description: The current status of the task, including its state and a descriptive message. required: - contextId - id - kind - status type: object TaskArtifactUpdateEvent: description: |- 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. properties: append: description: If true, the content of this artifact should be appended to a previously sent artifact with the same ID. type: boolean artifact: $ref: '#/definitions/Artifact' description: The artifact that was generated or updated. contextId: description: The context ID associated with the task. type: string kind: const: artifact-update description: The type of this event, used as a discriminator. Always 'artifact-update'. type: string lastChunk: description: If true, this is the final chunk of the artifact. type: boolean metadata: additionalProperties: {} description: Optional metadata for extensions. type: object taskId: description: The ID of the task this artifact belongs to. type: string required: - artifact - contextId - kind - taskId type: object TaskIdParams: description: Defines parameters containing a task ID, used for simple task operations. properties: id: description: The unique identifier (e.g. UUID) of the task. type: string metadata: additionalProperties: {} description: Optional metadata associated with the request. type: object required: - id type: object TaskNotCancelableError: description: An A2A-specific error indicating that the task is in a state where it cannot be canceled. properties: code: const: -32002 description: The error code for a task that cannot be canceled. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Task cannot be canceled description: The error message. type: string required: - code - message type: object TaskNotFoundError: description: An A2A-specific error indicating that the requested task ID was not found. properties: code: const: -32001 description: The error code for a task not found error. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: Task not found description: The error message. type: string required: - code - message type: object TaskPushNotificationConfig: description: A container associating a push notification configuration with a specific task. properties: pushNotificationConfig: $ref: '#/definitions/PushNotificationConfig' description: The push notification configuration for this task. taskId: description: The unique identifier (e.g. UUID) of the task. type: string required: - pushNotificationConfig - taskId type: object TaskQueryParams: description: Defines parameters for querying a task, with an option to limit history length. properties: historyLength: description: The number of most recent messages from the task's history to retrieve. type: integer id: description: The unique identifier (e.g. UUID) of the task. type: string metadata: additionalProperties: {} description: Optional metadata associated with the request. type: object required: - id type: object TaskResubscriptionRequest: description: Represents a JSON-RPC request for the `tasks/resubscribe` method, used to resume a streaming connection. properties: id: description: The identifier for this request. type: - string - integer jsonrpc: const: '2.0' description: The version of the JSON-RPC protocol. MUST be exactly "2.0". type: string method: const: tasks/resubscribe description: The method name. Must be 'tasks/resubscribe'. type: string params: $ref: '#/definitions/TaskIdParams' description: The parameters identifying the task to resubscribe to. required: - id - jsonrpc - method - params type: object TaskState: description: Defines the lifecycle states of a Task. enum: - submitted - working - input-required - completed - canceled - failed - rejected - auth-required - unknown type: string TaskStatus: description: Represents the status of a task at a specific point in time. properties: message: $ref: '#/definitions/Message' description: An optional, human-readable message providing more details about the current status. state: $ref: '#/definitions/TaskState' description: The current state of the task's lifecycle. timestamp: description: An ISO 8601 datetime string indicating when this status was recorded. examples: - '2023-10-27T10:00:00Z' type: string required: - state type: object TaskStatusUpdateEvent: description: |- 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. properties: contextId: description: The context ID associated with the task. type: string final: description: If true, this is the final event in the stream for this interaction. type: boolean kind: const: status-update description: The type of this event, used as a discriminator. Always 'status-update'. type: string metadata: additionalProperties: {} description: Optional metadata for extensions. type: object status: $ref: '#/definitions/TaskStatus' description: The new status of the task. taskId: description: The ID of the task that was updated. type: string required: - contextId - final - kind - status - taskId type: object TextPart: description: Represents a text segment within a message or artifact. properties: kind: const: text description: The type of this part, used as a discriminator. Always 'text'. type: string metadata: additionalProperties: {} description: Optional metadata associated with this part. type: object text: description: The string content of the text part. type: string required: - kind - text type: object TransportProtocol: description: Supported A2A transport protocols. enum: - JSONRPC - GRPC - HTTP+JSON type: string UnsupportedOperationError: description: An A2A-specific error indicating that the requested operation is not supported by the agent. properties: code: const: -32004 description: The error code for an unsupported operation. type: integer data: description: |- A primitive or structured value containing additional information about the error. This may be omitted. message: default: This operation is not supported description: The error message. type: string required: - code - message type: object