Shared contracts & helpers

Core · Interfaces & runtime guarantees · Back to layer index

Symbol	Kind	Purpose
AgentErrorInfo	interface	Stable error metadata for App diagnostics. Unknown retryability is deliberately omitted.
AsyncSink	type	Awaitable sink for an ordered stream. A rejection propagates to the emitter.
BudgetError	class	A configured allowance (rounds, model calls, attempts) is exhausted. The optional message states which allowance ran out; code is the stable marker.
CheckResult	interface	Verdict of one registered check. unavailable and not-run are not verdicts on the value: they state that the check could not produce an answer, so callers must not treat them as failures.
commonPrefixLength	function	Length of the longest common prefix of two strings. Implemented as a binary search over slice comparisons so long prompts stay on the native string comparison path instead of running a JavaScript character loop.
configureBreakWhile	function	Install the host-owned break observer. No logging or persistence is enabled by default; passing no argument (or an empty config) removes any previously installed observer.
DurationMs	type	Elapsed time in milliseconds; never an absolute instant.
ErrorContext	interface	Boundary metadata is recorded internally, without replacing the original thrown value.
ExecutionContext	interface	Required execution facts available inside a running call.
ExecutionOptions	interface	Optional controls accepted by any public Core call.
getErrorInfo	function	Produce a frozen diagnostic view of any thrown value. Inspection is guarded: an exotic error (revoked proxy, throwing getter, null prototype) degrades to UNKNOWN_ERROR instead of raising a second failure while handling the first.
Id	type	Opaque identifier. Format and meaning belong to the App or to the registering module.
InvocationMetadata	interface	Identity and timing shared by every invocation receipt.
InvocationResult	interface	A produced value together with the receipt of the invocation that produced it.
InvocationStatus	type	Terminal state of one invocation; cancelled is distinct from a failure.
Issue	interface	One validation problem, locatable by code and, when available, by field path.
JsonSchema	type	JSON Schema as consumed by the App's validator; Core never interprets its contents.
MaybePromise	type	A value that may already be resolved or still pending.
ModelCallRecord	interface	Receipt of a model call that returned successfully.
ModelResult	type	Model call result with its model-call receipt.
Observer	type	Notification callback. A rejected promise propagates to the emitter.
OperationContext	interface	Execution context plus the App-owned host object. app carries services, identity and per-request dependencies supplied by the host; Core treats it as opaque and must not depend on application-specific fields.
ProtocolRegistry	class	Append-only protocol registry. Extending Map keeps lookup semantics familiar while set rejects every invalid registration, which makes the instance effectively immutable after wiring.
ReadonlyCatalog	interface	Read-only projection of a definition set; the implementation owns ordering and validation.
Registry	interface	Mutable catalog. Registrations append; seal freezes the set against later writes.
retrievalQueryKey	function	Serialize a query into a stable structural key. Object keys are sorted recursively while array positions are preserved. Values that JSON cannot represent, such as functions or undefined, make JSON.stringify return undefined and therefore produce an error instead of a colliding key.
SchemaAdapter	interface	Compiled schema pair: the JSON form shown to the model and the runtime parser.
SearchHit	interface	One search result. score semantics stay algorithm-specific (direction and scale are not part of this contract), and document may be a projection that only exposes stored fields rather than the full record.
TimestampMs	type	Wall-clock instant in milliseconds since the Unix epoch.
ToolCallRecord	interface	Receipt of a tool call that returned successfully.
ToolResult	type	Tool call result with its tool-call receipt.
ValidationError	class	Rejected input or output that failed one or more registered checks. The message is fixed; consumers should read issues for the actual reasons.
WorkflowContractError	class	The workflow definition violates Core's execution contract, as opposed to failing business logic. Examples: unknown model binding, asynchronous predicate, unmatched route, missing state field. It is a programming error, so callers should not treat it as retryable.