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a2a

package

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Versions in this module

v0

v0.4.0

Aug 17, 2026

v0.3.0

Aug 14, 2026

v0.2.0

Aug 10, 2026

Changes in this version

+ var ErrInvalidToken = serverauth.ErrInvalidToken

+ var ErrTaskNotFound = errors.New("a2a: task not found")

+ var ErrUnavailable = errors.New("a2a: backend temporarily unavailable")

+ var NewStaticBearerValidator = serverauth.NewStaticBearerValidator

+ var NewTokenBucketLimiter = serverauth.NewTokenBucketLimiter

type AgentCard

+ Security []map[string][]string

+ SecuritySchemes *SecuritySchemes

+ type Backend interface

+ CancelTask func(ctx context.Context, taskID, reason string) (TaskInfo, error)

+ GetTask func(ctx context.Context, taskID string) (TaskInfo, error)

+ StreamMessage func(ctx context.Context, p SubmitParams, emit func(any)) (taskID string, info TaskInfo, err error)

+ SubmitMessage func(ctx context.Context, p SubmitParams) (taskID string, info TaskInfo, err error)

+ type Config struct

+ Backend Backend

+ BaseContext context.Context

+ CardDescription string

+ CardName string

+ CardVersion string

+ ExternalURL string

+ Limiter RateLimiter

+ Listen string

+ Logger *slog.Logger

+ Metric TaskMetric

+ Skills []ExposedSkill

+ Validator TokenValidator

+ type ExposedSkill struct

+ Description string

+ Scopes []string

+ SkillName string

+ Tags []string

+ WorkloadName string

+ type Principal = serverauth.Principal

+ type RateLimitRequest = serverauth.RateLimitRequest

+ type RateLimiter = serverauth.RateLimiter

+ type SecurityScheme struct

+ Scheme string

+ Type string

+ type SecuritySchemes struct

+ Bearer *SecurityScheme

+ type Server struct

+ func New(cfg Config) (*Server, error)

+ func (s *Server) Close() error

+ func (s *Server) Handler() http.Handler

+ func (s *Server) ListenAndServe() error

+ func (s *Server) Serve(ln net.Listener) error

+ func (s *Server) Shutdown(ctx context.Context) error

+ type StaticBearerValidator = serverauth.StaticBearerValidator

+ type SubmitParams struct

+ ContextID string

+ TaskID string

+ Text string

+ type TaskArtifactUpdateEvent struct

+ Append bool

+ Artifact Artifact

+ ContextID string

+ Kind string

+ LastChunk bool

+ Metadata map[string]any

+ TaskID string

+ type TaskInfo struct

+ ContextID string

+ Output string

+ State TaskState

+ StatusMessage string

+ WorkloadName string

+ type TaskMetric interface

+ A2ATask func(workload, outcome string)

+ type TaskStatusUpdateEvent struct

+ ContextID string

+ Final bool

+ Kind string

+ Metadata map[string]any

+ Status TaskStatus

+ TaskID string

+ type TokenBucketLimiter = serverauth.TokenBucketLimiter

+ type TokenValidator = serverauth.TokenValidator

v0.1.2

Jul 31, 2026

v0.1.1

Jul 31, 2026

v0.1.0

Jul 30, 2026

Changes in this version

+ const AuthTypeBearer

+ const DefaultTimeout

+ const ProtocolVersion

+ const Scheme

+ const TransportJSONRPC

+ const VersionHeader

+ const WellKnownCardPath

+ type Adapter struct

+ func NewAdapter(cfgs []AgentConfig, opts ...ClientOption) (*Adapter, error)

+ func (a *Adapter) Invoke(ctx context.Context, ref federation.Reference, inputs map[string]any, ...) (federation.Handle, error)

+ func (a *Adapter) Scheme() string

+ type AgentCard struct

+ AdditionalInterfaces []AgentInterface

+ Capabilities Capabilities

+ DefaultInputModes []string

+ DefaultOutputModes []string

+ Description string

+ Name string

+ PreferredTransport string

+ ProtocolVersion string

+ Skills []AgentSkill

+ URL string

+ Version string

+ type AgentConfig struct

+ AgentCardURL string

+ Auth *AuthConfig

+ Endpoint string

+ Filename string

+ Name string

+ Skills []string

+ TimeoutSeconds int

+ func LoadDir(dir string) ([]AgentConfig, error)

+ func (c AgentConfig) Timeout() time.Duration

+ func (c AgentConfig) Validate() error

+ type AgentInterface struct

+ Transport string

+ URL string

+ type AgentSkill struct

+ Description string

+ ID string

+ InputModes []string

+ Name string

+ OutputModes []string

+ Tags []string

+ type Artifact struct

+ ArtifactID string

+ Description string

+ Name string

+ Parts []Part

+ type AuthConfig struct

+ TokenEnv string

+ Type string

+ type Capabilities struct

+ PushNotifications bool

+ Streaming bool

+ type Client struct

+ func NewClient(cfg AgentConfig, opts ...ClientOption) (*Client, error)

+ func (c *Client) Card(ctx context.Context) (*AgentCard, error)

+ func (c *Client) Name() string

+ func (c *Client) Send(ctx context.Context, skill string, inputs map[string]any, ...) (*federation.Result, error)

+ type ClientOption func(*Client)

+ func WithHTTPClient(h *http.Client) ClientOption

+ func WithPollInterval(d time.Duration) ClientOption

+ type Message struct

+ ContextID string

+ Kind string

+ MessageID string

+ Metadata map[string]any

+ Parts []Part

+ Role string

+ TaskID string

+ type Part struct

+ Data map[string]any

+ Kind string

+ Metadata map[string]any

+ Text string

+ type RPCError struct

+ Code int

+ Data json.RawMessage

+ Message string

+ func (e *RPCError) Error() string

+ type Task struct

+ Artifacts []Artifact

+ ContextID string

+ ID string

+ Kind string

+ Status TaskStatus

+ type TaskState string

+ const TaskStateAuthRequired

+ const TaskStateCanceled

+ const TaskStateCompleted

+ const TaskStateFailed

+ const TaskStateInputRequired

+ const TaskStateRejected

+ const TaskStateSubmitted

+ const TaskStateWorking

+ func (s TaskState) Terminal() bool

+ type TaskStatus struct

+ Message *Message

+ State TaskState

v0.1.0-pre

Jul 26, 2026