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a2a

package

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Versions in this module

v1

v1.10.4

Nov 4, 2026

v1.10.3

Oct 30, 2026

v1.10.2

Oct 30, 2026

v1.10.1

Oct 30, 2026

v1.10.0

Oct 30, 2026

Changes in this version

+ func WithReplyRoute(ctx context.Context, route ReplyRoute) context.Context

+ type Admitter interface

+ AdmitRun func(ctx context.Context) (context.Context, func(), error)

type AskResult

+ ReplyBy time.Time

type Bus

+ func (b *Bus) ReplyForRun(ctx context.Context, route ReplyRoute, output string, runErr error) error

type BusConfig

+ Admitter Admitter

+ type ReplyRoute struct

+ ConversationID id.ConversationID

+ InReplyTo string

+ Ontology string

+ Protocol string

+ Receiver Address

+ Sender Address

+ func ReplyRouteFrom(ctx context.Context) (ReplyRoute, context.Context, bool)

v1.9.0

Oct 27, 2026

Changes in this version

+ const DefaultDeliveryClaimTTL

+ const DefaultHopCeiling

+ const DefaultReplyBy

+ const DefaultSweepInterval

+ const DefaultWorkers

+ const DeliveryDelivered

+ const DeliveryDelivering

+ const DeliveryFailed

+ const DeliveryQueued

+ const HandoffLanguage

+ const HandoffProtocol

+ const HeldAskMetadata

+ const ProtocolContractNet

+ const ProtocolQuery

+ const ProtocolRequest

+ const RecipientFailed

+ const RecipientSucceeded

+ const RecipientWaiting

+ const StatusClosed

+ const StatusExpired

+ const StatusOpen

+ var ErrAskAlreadyClaimed = errors.New("cortex: a2a: pending ask already claimed")

+ var ErrAskNeedsDirective = errors.New("cortex: a2a: ask needs a directive performative")

+ var ErrAskNeedsReceivers = errors.New("cortex: a2a: ask needs at least one receiver")

+ var ErrAskNotFound = errors.New("cortex: a2a: pending ask not found")

+ var ErrAskResolutionConflict = errors.New("cortex: a2a: ask resolution conflict")

+ var ErrAskResolutionNotFound = errors.New("cortex: a2a: ask resolution not found")

+ var ErrAskResolutionUnavailable = errors.New("cortex: a2a: atomic ask resolution unavailable")

+ var ErrConversationClosed = errors.New("cortex: a2a: conversation is closed")

+ var ErrConversationNotFound = errors.New("cortex: a2a: conversation not found")

+ var ErrDeliveryAlreadyClaimed = errors.New("cortex: a2a: delivery already claimed")

+ var ErrDeliveryBindingUnavailable = errors.New("cortex: a2a: delivery run binding unavailable")

+ var ErrDeliveryClaimLost = errors.New("cortex: a2a: delivery claim lost")

+ var ErrDeliveryNotFound = errors.New("cortex: a2a: delivery not found")

+ var ErrHeldAskConflict = errors.New("cortex: a2a: held question binding conflict")

+ var ErrHeldAskNotFound = errors.New("cortex: a2a: held question release not found")

+ var ErrHeldAskUnavailable = errors.New("cortex: a2a: durable held question release unavailable")

+ var ErrHopCeiling = errors.New("cortex: a2a: conversation hop ceiling exceeded")

+ var ErrInvalidPerformative = errors.New("cortex: a2a: unknown performative")

+ var ErrMessageNotFound = errors.New("cortex: a2a: message not found")

+ var ErrNoReceivers = errors.New("cortex: a2a: envelope has no receivers")

+ var ErrNoRunner = errors.New("cortex: a2a: no agent runner configured")

+ var ErrNoSender = errors.New("cortex: a2a: envelope has no sender")

+ var ErrNoStore = errors.New("cortex: a2a: no store configured")

+ var ErrRecipientDiscoveryUnavailable = errors.New("cortex: a2a: recipient discovery unavailable")

+ var ErrRecipientObservationUnavailable = errors.New("cortex: a2a: recipient observation unavailable")

+ var ErrReplyBinding = errors.New("cortex: a2a: invalid reply binding")

+ var ErrReplyCommitConflict = errors.New("cortex: a2a: reply commit conflict")

+ var ErrReplyCommitNotFound = errors.New("cortex: a2a: reply commit not found")

+ var ErrReplyCommitUnavailable = errors.New("cortex: a2a: atomic reply commit unavailable")

+ var ErrRosterDenied = errors.New("cortex: a2a: endpoint outside participant roster")

+ var ErrRosterUnavailable = errors.New("cortex: a2a: participant roster unavailable")

+ var ErrRoutingUnavailable = errors.New("cortex: a2a: orchestration routing unavailable")

+ var ErrSelfAddressed = errors.New("cortex: a2a: envelope is self-addressed")

+ var ErrUnknownReceiver = errors.New("cortex: a2a: receiver does not resolve")

+ var ErrUnroutable = errors.New("cortex: a2a: no transport handles that address")

+ func IsHandoffProtocol(protocol, language string) bool

+ func RenderInput(e *Envelope) string

+ func RoutingDiscoveryScope(ctx context.Context) (cortex.Scope, bool, error)

+ func RoutingOrchestration(ctx context.Context) string

+ type Address struct

+ Agent string

+ Node string

+ func ParseAddress(s string) Address

+ func (a Address) Equal(other Address) bool

+ func (a Address) IsLocal() bool

+ func (a Address) IsZero() bool

+ func (a Address) String() string

+ type AskParams struct

+ AskerRunID id.AgentRunID

+ DurableHold bool

+ Hold bool

+ ToolCallID string

+ type AskReply struct

+ Complete bool

+ Replies []AskReplyItem

+ type AskReplyItem struct

+ Content string

+ ConversationID string

+ Performative string

+ Sender string

+ type AskResolution struct

+ Ask PendingAsk

+ BindingDigest string

+ Fresh bool

+ OutcomeDigest string

+ Payload string

+ ResolutionID string

+ SchemaVersion int

+ SealedAt time.Time

+ type AskResolutionPage struct

+ Next string

+ Resolutions []AskResolution

+ type AskResolutionStore interface

+ GetAskResolution func(context.Context, string) (AskResolution, error)

+ ListAskResolutions func(context.Context, string, int) (AskResolutionPage, error)

+ ReadPendingAsk func(context.Context, string) (*PendingAsk, error)

+ SealAskResolution func(context.Context, *PendingAsk, AskReply) (AskResolution, error)

+ type AskResult struct

+ ConversationID id.ConversationID

+ MessageID id.MessageID

+ ReplyWith string

+ ToolCallID string

+ type AtomicMessageStore interface

+ RecordMessage func(context.Context, *Envelope) (*Envelope, error)

+ type Bus struct

+ func NewBus(cfg BusConfig) (*Bus, error)

+ func (b *Bus) AddTransport(t Transport)

+ func (b *Bus) Ask(ctx context.Context, p AskParams) (*AskResult, error)

+ func (b *Bus) Drain(ctx context.Context) (int, error)

+ func (b *Bus) HeldAskPending(ctx context.Context, token string) (bool, error)

+ func (b *Bus) Inbox(ctx context.Context, agentName string, f InboxFilter) ([]InboxItem, error)

+ func (b *Bus) ParticipantAddress(ctx context.Context, agentID id.AgentID) (Address, error)

+ func (b *Bus) PendingDispatch(ctx context.Context) (bool, error)

+ func (b *Bus) ReclaimStaleDeliveries(ctx context.Context) (int, error)

+ func (b *Bus) RecoverRecipient(ctx context.Context, key id.DeliveryID, ...) (ReservedReply, error)

+ func (b *Bus) RecoverRecipients(ctx context.Context, after id.DeliveryID) (RecipientRecoveryPage, error)

+ func (b *Bus) Redrive(ctx context.Context) (int, error)

+ func (b *Bus) Release(ctx context.Context, res *AskResult) error

+ func (b *Bus) ReleasePausedAsk(ctx context.Context, req HeldAskRequest) (HeldAskReceipt, error)

+ func (b *Bus) Send(ctx context.Context, p SendParams) (*SendResult, error)

+ func (b *Bus) Start(ctx context.Context) error

+ func (b *Bus) Stop()

+ func (b *Bus) SupportsHeldAskRelease() bool

+ func (b *Bus) SweepExpiredAsks(ctx context.Context) (int, error)

+ type BusConfig struct

+ Clock Clock

+ HandoffHandler HandoffHandler

+ Hooks HookEmitter

+ Metrics gometrics.Metrics

+ Options Options

+ OrchestrationID id.OrchestrationID

+ RecipientObserver RecipientObserver

+ RecipientRecovery *RecipientRecoveryConfig

+ ReservedRunner cortex.ReservedAgentRunner

+ Resolver Resolver

+ Resumer Resumer

+ Roster *Roster

+ Runner cortex.AgentRunner

+ Store Store

+ Synchronous bool

+ Transports []Transport

+ type Class string

+ const ClassControl

+ const ClassDirective

+ const ClassInformative

+ type Clock interface

+ Now func() time.Time

+ type ContractNetParams struct

+ AskerRunID id.AgentRunID

+ Content string

+ Initiator Address

+ Ontology string

+ Recipients []Address

+ ReplyBy *time.Time

+ ToolCallID string

+ type Conversation struct

+ Deadline *time.Time

+ HopCeiling int

+ HopsUsed int

+ ID id.ConversationID

+ Initiator Address

+ OrchestrationID string

+ Participants []Address

+ PeerContext string

+ PeerNode string

+ Protocol string

+ Scope cortex.Scope

+ Status string

+ func (c *Conversation) AddParticipant(addr Address)

+ func (c *Conversation) HasParticipant(addr Address) bool

+ func (c *Conversation) IsOpen() bool

+ type ConversationListFilter struct

+ Exact bool

+ Limit int

+ Offset int

+ Status string

+ type Delivery struct

+ ClaimToken string

+ ClaimedAt *time.Time

+ DeliveredAt *time.Time

+ Error string

+ ID id.DeliveryID

+ MessageID id.MessageID

+ OrchestrationID string

+ ReadAt *time.Time

+ Receiver Address

+ RunID id.AgentRunID

+ Scope cortex.Scope

+ State string

+ type DeliveryAdmissionError struct

+ func (e *DeliveryAdmissionError) DeliveryIdentity() id.DeliveryID

+ func (e *DeliveryAdmissionError) Error() string

+ func (e *DeliveryAdmissionError) RunIdentity() id.AgentRunID

+ func (e *DeliveryAdmissionError) Unwrap() error

+ type DeliveryOutcome struct

+ DeliveryID id.DeliveryID

+ Error string

+ Receiver Address

+ Status string

+ type DeliveryRunBinder interface

+ BindDeliveryRun func(context.Context, *Delivery, id.AgentRunID) error

+ type Envelope struct

+ Content string

+ ConversationID id.ConversationID

+ Encoding string

+ Hops int

+ ID id.MessageID

+ InReplyTo string

+ Language string

+ Metadata map[string]any

+ Ontology string

+ OrchestrationID string

+ OriginRunID id.AgentRunID

+ Performative Performative

+ Protocol string

+ Receivers []Address

+ ReplyBy *time.Time

+ ReplyTo []Address

+ ReplyWith string

+ Scope cortex.Scope

+ Sender Address

+ func (e *Envelope) Validate() error

+ type HandoffHandler interface

+ ReceiveHandoff func(context.Context, *Envelope) error

+ ValidateHandoff func(context.Context, *Envelope) error

+ type HeldAskReceipt struct

+ CommittedAt time.Time

+ Deliveries []id.DeliveryID

+ Fresh bool

+ MessageID id.MessageID

+ OrchestrationID string

+ Request HeldAskRequest

+ SchemaVersion int

+ Scope cortex.Scope

+ type HeldAskRequest struct

+ ReplyWith string

+ RunID id.AgentRunID

+ RunRevision int64

+ SuspensionID id.SuspensionID

+ type HeldAskStore interface

+ GetHeldAskRelease func(context.Context, string) (HeldAskReceipt, error)

+ ReleaseHeldAsk func(context.Context, HeldAskRequest) (HeldAskReceipt, error)

+ type HookEmitter interface

+ MessageDelivered func(ctx context.Context, msgID id.MessageID, to string)

+ MessageRefused func(ctx context.Context, msgID id.MessageID, to, reason string)

+ MessageSent func(ctx context.Context, msgID id.MessageID, from, to, performative string)

+ type InboxFilter struct

+ ConversationID id.ConversationID

+ Limit int

+ Offset int

+ UnreadOnly bool

+ type InboxItem struct

+ Content string

+ ConversationID string

+ DeliveryID string

+ MessageID string

+ Performative string

+ ReceivedAt string

+ Sender string

+ type MessageListFilter struct

+ ConversationID id.ConversationID

+ Exact bool

+ Limit int

+ Offset int

+ type Options struct

+ DefaultReplyBy time.Duration

+ DeliveryClaimTTL time.Duration

+ HopCeiling int

+ SweepInterval time.Duration

+ Workers int

+ type PendingAsk struct

+ AskerAgent string

+ AskerRunID id.AgentRunID

+ ClaimedAt *time.Time

+ ConversationID id.ConversationID

+ Deadline *time.Time

+ Expected Address

+ MessageID id.MessageID

+ OrchestrationID string

+ ReplyWith string

+ Scope cortex.Scope

+ ToolCallID string

+ type Performative string

+ const AcceptProposal

+ const Agree

+ const CFP

+ const Cancel

+ const Confirm

+ const Disconfirm

+ const Failure

+ const Inform

+ const InformIf

+ const InformRef

+ const NotUnderstood

+ const Propagate

+ const Propose

+ const Proxy

+ const QueryIf

+ const QueryRef

+ const Refuse

+ const RejectProposal

+ const Request

+ const RequestWhen

+ const RequestWhenever

+ const Subscribe

+ func AllPerformatives() []Performative

+ func (p Performative) AnswersAsk() bool

+ func (p Performative) Class() (Class, bool)

+ func (p Performative) Valid() bool

+ type Proposal struct

+ Content string

+ From Address

+ type RecipientDiscoveryStore interface

+ ListDeferredRecipients func(context.Context, id.DeliveryID, int) ([]id.DeliveryID, error)

+ type RecipientObservation struct

+ AgentName string

+ Output string

+ RunID id.AgentRunID

+ State string

+ type RecipientObserver interface

+ ObserveRecipient func(context.Context, RecipientRequest) (RecipientObservation, error)

+ type RecipientRecoveryConfig struct

+ AttemptTimeout time.Duration

+ AuthorizeDelivery func(context.Context, id.OrchestrationID, id.DeliveryID) error

+ AuthorizeDiscovery func(context.Context, id.OrchestrationID) error

+ BatchSize int

+ ReportError func(context.Context, error)

+ type RecipientRecoveryPage struct

+ Completed int

+ Examined int

+ Failed int

+ Next id.DeliveryID

+ Waiting int

+ type RecipientRequest struct

+ AgentName string

+ OrchestrationID id.OrchestrationID

+ RunID id.AgentRunID

+ type ReservedReply struct

+ CommittedAt time.Time

+ DeliveryID id.DeliveryID

+ Fresh bool

+ OrchestrationID string

+ ReplyDeliveryID id.DeliveryID

+ ReplyMessageID id.MessageID

+ RequestDigest string

+ RunID id.AgentRunID

+ SchemaVersion int

+ Scope cortex.Scope

+ type ReservedReplyStore interface

+ CommitReservedReply func(context.Context, *Delivery, string, bool) (ReservedReply, error)

+ GetReservedReply func(context.Context, id.DeliveryID) (ReservedReply, error)

+ type ResolutionResumer interface

+ ResumeAgentResolution func(context.Context, AskResolution) error

+ type Resolver interface

+ ResolveAddress func(ctx context.Context, addr Address) error

+ type Resumer interface

+ ResumeAgentReply func(ctx context.Context, runID id.AgentRunID, callID, result string) error

+ type Roster struct

+ Participants []RosterParticipant

+ Scope cortex.Scope

+ type RosterParticipant struct

+ AgentID id.AgentID

+ Name string

+ type RoutingBackend interface

+ SupportsOrchestrationRouting func() bool

+ type ScopedRoutingBackend interface

+ SupportsScopedOrchestrationDiscovery func() bool

+ type SendParams struct

+ Content string

+ ConversationID id.ConversationID

+ Encoding string

+ InReplyTo string

+ Language string

+ Metadata map[string]any

+ Ontology string

+ OriginRunID id.AgentRunID

+ PeerContext string

+ PeerNode string

+ Performative Performative

+ Protocol string

+ Receivers []Address

+ ReplyBy *time.Time

+ ReplyTo []Address

+ ReplyWith string

+ Sender Address

+ type SendResult struct

+ ConversationID id.ConversationID

+ Deliveries []DeliveryOutcome

+ MessageID id.MessageID

+ type Store interface

+ ClaimDelivery func(ctx context.Context, deliveryID id.DeliveryID) (*Delivery, error)

+ ClaimPendingAsk func(ctx context.Context, replyWith string) (*PendingAsk, error)

+ CreateConversation func(ctx context.Context, c *Conversation) error

+ CreateDelivery func(ctx context.Context, d *Delivery) error

+ CreateMessage func(ctx context.Context, e *Envelope) error

+ CreatePendingAsk func(ctx context.Context, a *PendingAsk) error

+ GetConversation func(ctx context.Context, convID id.ConversationID) (*Conversation, error)

+ GetConversationByPeerContext func(ctx context.Context, node, peerContext string) (*Conversation, error)

+ GetDelivery func(ctx context.Context, deliveryID id.DeliveryID) (*Delivery, error)

+ GetMessage func(ctx context.Context, msgID id.MessageID) (*Envelope, error)

+ ListConversations func(ctx context.Context, filter *ConversationListFilter) ([]*Conversation, error)

+ ListExpiredAsks func(ctx context.Context, now time.Time, limit int) ([]*PendingAsk, error)

+ ListInbox func(ctx context.Context, agentName string, filter InboxFilter) ([]*Delivery, error)

+ ListMessages func(ctx context.Context, filter *MessageListFilter) ([]*Envelope, error)

+ ListPendingAsksByConversation func(ctx context.Context, convID id.ConversationID) ([]*PendingAsk, error)

+ ListQueuedDeliveries func(ctx context.Context, limit int) ([]*Delivery, error)

+ MarkDeliveryRead func(ctx context.Context, deliveryID id.DeliveryID) error

+ ReclaimStaleDeliveries func(ctx context.Context, olderThan time.Time, limit int) (int, error)

+ UpdateConversation func(ctx context.Context, c *Conversation) error

+ UpdateDelivery func(ctx context.Context, d *Delivery) error

+ func NewRoutingStore(s Store, key id.OrchestrationID) (Store, error)

+ type Tender struct

+ Complete bool

+ ConversationID id.ConversationID

+ Proposals []Proposal

+ Refusals []Proposal

+ ReplyWith string

+ func CollectTender(ctx context.Context, b *Bus, convID id.ConversationID, replyWith string) (*Tender, error)

+ func ContractNet(ctx context.Context, b *Bus, p ContractNetParams) (*Tender, error)

+ type Transport interface

+ Deliver func(ctx context.Context, e *Envelope, receiver Address) error

+ Handles func(addr Address) bool

v1.8.0

Oct 18, 2026

v1.7.1

Oct 11, 2026

v1.7.0

Oct 9, 2026