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Interface: DispatchContext

Defined in: src/lib/contracts/dispatch_context.ts:327

Context object for a single LLM execution call.

Remarks

Mirrors the surface of @nhtio/adk!TurnContext but is path-agnostic — it knows nothing about a parent context. Mutations apply to local Sets immediately, call persistence callbacks immediately, and fire the corresponding mutation hook (storedMemory, mutatedMemory, deletedMemory, etc.) in both standalone and derived dispatches.

The @nhtio/adk!DispatchRunner is the only thing that creates a context with a parent relationship: when dispatched with a source: TurnContext, the runner subscribes to the mutation hooks, queues deltas internally, and flushes them to the parent's Sets at the end of each iteration. The context itself remains unaware of the parent.

Middleware/executor signals termination via DispatchContext.ack (clean completion) or DispatchContext.nack (failure). Both set an internal flag the runner reads at end-of-iteration to decide whether to loop or exit. DispatchContext.isSignalled, DispatchContext.isAcked, and DispatchContext.nackError are publicly readable getters so middleware can inspect signal state and bail early.

Properties

PropertyModifierTypeDescriptionDefined in
abortreadonly(reason?: unknown) => voidAborts the dispatch's AbortController with the supplied reason. Middleware should call this when refusing to proceed — the runner short-circuits cleanly, dispatchEnd.status resolves to 'aborted', and no error event is emitted.src/lib/contracts/dispatch_context.ts:1068
abortedreadonlybooleantrue when the abort controller signal has fired.src/lib/contracts/dispatch_context.ts:1060
abortSignalreadonlyAbortSignalThe AbortSignal from the execution's AbortController.src/lib/contracts/dispatch_context.ts:1062
deleteMemoryreadonly(id: string) => Promise<void>Removes a memory from the local Set and persistence layer by ID.src/lib/contracts/dispatch_context.ts:1120
deleteMessagereadonly(id: string) => Promise<void>Removes a message from the local Set and persistence layer by ID.src/lib/contracts/dispatch_context.ts:1132
deleteRetrievablereadonly(id: string) => Promise<void>Removes a retrievable record from the local Set and persistence layer by ID.src/lib/contracts/dispatch_context.ts:1126
deleteStandingInstructionreadonly(v: string | Tokenizable) => Promise<void>Removes a standing instruction from the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1114
deleteThoughtreadonly(id: string) => Promise<void>Removes a thought from the local Set and persistence layer by ID.src/lib/contracts/dispatch_context.ts:1138
deleteToolCallreadonly(id: string) => Promise<void>Removes a tool call from the local Set and persistence layer by ID.src/lib/contracts/dispatch_context.ts:1144
dispatchIdreadonlystringStable identifier for the dispatch this context belongs to; set by DispatchRunner.src/lib/contracts/dispatch_context.ts:1056
emitMessagereadonlyEmitMessageFnEmits a message hook; fires registered handlers synchronously.src/lib/contracts/dispatch_context.ts:1174
emitThoughtreadonlyEmitThoughtFnEmits a thought hook; fires registered handlers synchronously.src/lib/contracts/dispatch_context.ts:1176
emitToolCallreadonlyEmitToolCallFnEmits a toolCall hook; fires registered handlers synchronously.src/lib/contracts/dispatch_context.ts:1178
emitToolExecutionEndreadonlyEmitToolExecutionEndFnEmits a toolExecutionEnd hook; fires registered handlers synchronously.src/lib/contracts/dispatch_context.ts:1182
emitToolExecutionStartreadonlyEmitToolExecutionStartFnEmits a toolExecutionStart hook; fires registered handlers synchronously.src/lib/contracts/dispatch_context.ts:1180
fetchMemoriesreadonly() => | Memory[] | Promise<Memory[]>Fetches memories; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1094
fetchMessagesreadonly() => | Message[] | Promise<Message[]>Fetches messages; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1098
fetchRetrievablesreadonly() => | Retrievable[] | Promise<Retrievable[]>Fetches retrievable records; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1096
fetchThoughtsreadonly() => | Thought[] | Promise<Thought[]>Fetches thoughts; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1100
fetchToolCallsreadonly() => | ToolCall[] | Promise<ToolCall[]>Fetches tool calls; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1102
fetchToolsreadonly() => | Tool<SpooledArtifact>[] | Promise<Tool<SpooledArtifact>[]>Fetches tools; delegates to the callback supplied at construction.src/lib/contracts/dispatch_context.ts:1104
idreadonlystringUnique identifier for this execution context, generated as UUIDv6 at construction time.src/lib/contracts/dispatch_context.ts:1054
isAckedreadonlybooleantrue when the context was signalled via DispatchContext.ack.src/lib/contracts/dispatch_context.ts:1072
isSignalledreadonlybooleantrue once DispatchContext.ack or DispatchContext.nack has been called.src/lib/contracts/dispatch_context.ts:1070
iterationreadonlynumber0-based iteration count within the current dispatch; updated by DispatchRunner.src/lib/contracts/dispatch_context.ts:1058
mutateMemoryreadonly(v: Memory) => Promise<void>Updates an existing memory in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1118
mutateMessagereadonly(v: Message) => Promise<void>Updates an existing message in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1130
mutateRetrievablereadonly(v: Retrievable) => Promise<void>Updates an existing retrievable record in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1124
mutateStandingInstructionreadonly(v: string | Tokenizable) => Promise<void>Updates an existing standing instruction in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1112
mutateThoughtreadonly(v: Thought) => Promise<void>Updates an existing thought in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1136
mutateToolCallreadonly(v: ToolCall) => Promise<void>Updates an existing tool call in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1142
nackErrorreadonlyError | undefinedThe error stored by DispatchContext.nack, or undefined if not nacked.src/lib/contracts/dispatch_context.ts:1074
refreshStandingInstructionsreadonly() => | (string | Tokenizable)[] | Promise<(string | Tokenizable)[]>Refreshes and returns standing instructions.src/lib/contracts/dispatch_context.ts:1106
standingInstructionsreadonlySet<Tokenizable>Standing instructions for this execution, in insertion order.src/lib/contracts/dispatch_context.ts:1080
stashreadonlyRegistryArbitrary key-value store for cross-step state.src/lib/contracts/dispatch_context.ts:1076
storeMediaBytesreadonly(id: string, bytes: ConduitBytes) => | MediaReader | Promise<MediaReader>Persists tool-generated media bytes into consumer storage and returns a @nhtio/adk!MediaReader. Remarks This is a low-level persistence conduit, NOT a mutation: it does not add to turnMessages/ turnToolCalls or fire a stored* hook. The handler builds a @nhtio/adk!Media from the returned reader (Media.toolGenerated({ reader })) and stores the owning primitive — a @nhtio/adk!Message attachment or @nhtio/adk!ToolCall result — via the relevant store* method separately. Persisting bytes without storing the primitive means the framework never sees the media.src/lib/contracts/dispatch_context.ts:1156
storeMemoryreadonly(v: Memory) => Promise<void>Stores a new memory in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1116
storeMessagereadonly(v: Message) => Promise<void>Stores a new message in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1128
storeRetrievablereadonly(v: Retrievable) => Promise<void>Stores a new retrievable record in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1122
storeRetrievableBytesreadonly(id: string, bytes: ConduitBytes) => | SpoolReader | Promise<SpoolReader>Persists extracted retrievable text bytes into consumer storage and returns a @nhtio/adk!SpoolReader. Remarks Low-level persistence conduit, same posture as DispatchContext.storeMediaBytes: returns a value, touches no Sets, fires no hook. Wrap the reader in a @nhtio/adk!SpooledArtifact and pass it as Retrievable.content, then persist the record via DispatchContext.storeRetrievable.src/lib/contracts/dispatch_context.ts:1169
storeStandingInstructionreadonly(v: string | Tokenizable) => Promise<void>Stores a new standing instruction in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1110
storeThoughtreadonly(v: Thought) => Promise<void>Stores a new thought in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1134
storeToolCallreadonly(v: ToolCall) => Promise<void>Stores a new tool call in the local Set and persistence layer.src/lib/contracts/dispatch_context.ts:1140
systemPromptreadonlyTokenizableThe system prompt for this execution.src/lib/contracts/dispatch_context.ts:1078
toolsreadonlyToolRegistryTool registry for this execution.src/lib/contracts/dispatch_context.ts:1092
turnMemoriesreadonlySet<Memory>Memories loaded for this execution.src/lib/contracts/dispatch_context.ts:1082
turnMessagesreadonlySet<Message>Messages loaded for this execution.src/lib/contracts/dispatch_context.ts:1086
turnRetrievablesreadonlySet<Retrievable>Retrievable records loaded for this execution.src/lib/contracts/dispatch_context.ts:1084
turnThoughtsreadonlySet<Thought>Thoughts loaded for this execution.src/lib/contracts/dispatch_context.ts:1088
turnToolCallsreadonlySet<ToolCall>Tool calls loaded for this execution.src/lib/contracts/dispatch_context.ts:1090
waitForreadonlyOpenGateFnOpens a gate and suspends until it resolves, rejects, times out, or is aborted.src/lib/contracts/dispatch_context.ts:1184

Methods

ack()

ts
ack(): void;

Defined in: src/lib/contracts/dispatch_context.ts:970

Signals successful completion of this execution.

Returns

void

Remarks

Sets the context's internal signal flag. The @nhtio/adk!DispatchRunner reads the flag at the end of each iteration to decide whether to loop or exit. Calling ack() does NOT abort the current iteration — the current pipeline and flush complete first.

Throws

@nhtio/adk!E_LLM_EXECUTION_ALREADY_SIGNALLED when the context has already been signalled (whether via ack() or nack()).


nack()

ts
nack(error?: Error): void;

Defined in: src/lib/contracts/dispatch_context.ts:1028

Signals failed completion of this execution, optionally with an error.

Parameters

ParameterTypeDescription
error?ErrorOptional error describing the failure. If omitted, a generic Error is used.

Returns

void

Remarks

Sets the context's internal signal flag and stores the error. The @nhtio/adk!DispatchRunner reads the flag at the end of each iteration and surfaces the error via the dispatchEnd observability payload and as the rejection reason of dispatch(). Calling nack() does NOT abort the current iteration — the current pipeline and flush complete first.

Throws

@nhtio/adk!E_LLM_EXECUTION_ALREADY_SIGNALLED when the context has already been signalled.


onAck()

ts
onAck(handler: () => void): () => void;

Defined in: src/lib/contracts/dispatch_context.ts:1009

Registers a handler to run when this context completes successfully via ack.

Parameters

ParameterTypeDescription
handler() => voidCallback invoked when ack() is called.

Returns

An unsubscribe function that removes the handler.

() => void

Remarks

The handler does NOT fire on nack — failed executor runs should leave any ack-tied subscriptions alone so the consumer can inspect what was registered when debugging the failure. Returns an unsubscribe function; subscriptions are short-lived and die with the context regardless.

The canonical consumer is ToolRegistry.bindContext(ctx), which uses this hook to drop ephemeral tools (notably forged artifact-query tools from SpooledArtifact.forgeTools(ctx)) at ctx-completion. Consumers may also register custom handlers here for any per-executor cleanup.

See


toolCallCount()

ts
toolCallCount(checksum: string): number;

Defined in: src/lib/contracts/dispatch_context.ts:955

Returns how many times a tool call with the given checksum has been stored in this execution.

Parameters

ParameterTypeDescription
checksumstringThe ToolCall.checksum value to look up.

Returns

number

Remarks

Checksums are computed over tool + args (see @nhtio/adk!ToolCall.checksum). This count lets the executor detect repeat invocations of the same call without scanning the full Set. Returns 0 when the checksum has not been seen.