Complete API index

Grouped by responsibility and usage. Includes 46 public modules, 649 standalone symbols and 547 callable members. Aggregating entry points that share one implementation reuse the same page.

Each page covers declarations, parameters, results, fields, members and related examples. Core accepts contract implementations, Support provides recommended implementations, and Kits are chosen by the App.

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Core · Interfaces & runtime guarantees

Transport & streaming

Open group

Symbol	Kind	Purpose
abortableStream	function	Re-yield an async iterable, but reject as soon as signal aborts. The abort reason is propagated unchanged, so callers can tell user cancellation from a provider failure without inspecting messages.
readSse	function	Decode an SSE response body into events. Framing contract: - A network chunk is not an event. Bytes are buffered until a blank line, because UTF-8 sequences, CRLF pairs and data: lines may all straddle chunk boundaries. - \r\n, \r and \n all terminate a line; a trailing \r at the end of a chunk is held back until the next chunk shows whether an \n follows. - Comment lines (leading :) are discarded; they are used as heartbeats. - The size limit applies per line and per event (1 MiB), not per network read, so many complete events coalesced into one chunk after backpressure remain valid. - Cancellation is checked between lines, so aborting while the consumer is paused stops emitting the remaining buffered events of the same chunk.
SseEvent	interface	One dispatched SSE event, assembled from all lines up to a blank line.
SseIdleTimeoutError	class	Raised when no bytes arrive within the configured idle window. A distinct type lets callers treat a silent connection as retryable instead of mixing it with transport or decoding failures.
SseReadOptions	type	Per-read configuration; snapshotted when readSse starts.

Execution & workflows

Open group

Symbol	Kind	Purpose
AgentBranch	interface	Immutable identity of one branch of an agent. The three required ids are generated per engine unless the host restores a branch; the optional ids are only present on a fork and record the exact origin, so a forked run can be attributed without consulting external storage.
AgentCacheAddress	interface	Exact immutable address passed to the App port, including cancellation for this visit.
AgentCacheOptions	interface	Persistent and volatile storage are independent; there is no implicit fallback or mirroring.
AgentCachePort	interface	App-owned storage. Capacity, expiry, serialization and user isolation belong to the App.
AgentCheckpoint	interface	In-memory checkpoint with a copy-on-read accessor. The stored data is already a clone, and read clones again, so a caller cannot mutate the checkpoint by mutating what it read.
AgentCheckpointRecord	interface	Host-owned serializable data, never a saved credential, model budget or executable handler.
AgentCoreEngine	class	Bounded execution shared by applications; business rules are registered by each host. Configuration is bound before a run and may be bound only once per model, tool runtime and workflow. A run resolves its signal from the engine, the request runtime and the caller, then executes either the bound workflow or a supplied step function until the round budget, cancellation or a completion stops it.
AgentCoreEngineOptions	interface	Engine construction options.
AgentCoreEngineSetup	type	Engine construction options. Combines round budget and error factories with exactly one model shape (a single bound model or a named catalog), an optional tool runtime, an optional branch identity, and an optional workflow together with its App dependencies.
AgentModelBinding	type	Model binding accepted by the engine. Execution scope belongs to the engine, so a bound model may not carry its own signal or execution options.
AgentModelRuntime	type	The subset of a runner an engine may drive; kept small so the App can supply it.
AgentWorkflow	class	Executable catalog: validate references and bounded cycles before any handler runs. Validation happens once, at construction, so traversal can assume every target exists and every cycle is budget-bounded.
AgentWorkflowDefinition	type	The graph an engine executes.
AttemptBudget	class	Successful acquisitions consume attempts; a refused acquisition never grants another. available is a snapshot of the counter, not a reservation: a caller must still call take and honor its boolean result before acting.
CacheContext	interface	Cache access shared by workflow visits and the low-level $step loop.
CacheReadOptions	interface	Only reads may name another node. Partition names are not authorization boundaries.
CoreStep	type	One loop iteration. Must be re-entrant: the same step object runs every round.
defineWorkflow	function	Build a validated workflow from a definition.
EngineCacheOptions	interface	Optional Engine memory bounds; TTL is measured from the latest write.
ExecutionEventDescriptor	interface	Event name, content class and the producing execution identity.
ExecutionObserver	interface	Live consumer of Core facts.
LoopEvent	interface	Progress fact for one loop round, correlated with the enclosing diagnostics span.
NodeAgentCache	interface	Async node view. Writes and clear can only address the current partition.
NodeCache	interface	Synchronous view of the current node's Engine-owned memory. Values retain identity.
requireWorkflowValue	function	Read a state field that must already be present. Used by requires declarations and terminal deliveries, so a node cannot observe a field as undefined and silently produce a wrong result.
route	function
StepOutcome	type	Decision a step returns to the engine.
WorkflowChain	interface	Observed visits, never merged by static node id or synthesized from adjacency.
WorkflowChainCoverage	interface	Capture completeness is independent of whether diagnostic content was included.
WorkflowChainNode	interface	A single node visit, with flat ordered subflow records including every independent fix.
WorkflowChainNodeEvent	interface	Node-local lifecycle facts; payload remains subject to the source's content policy.
WorkflowChainSource	type	App resolves authorization, retention, pagination and storage paths before returning.
WorkflowChainTransition	interface	Actual handoff evidence; a target span does not prove its enter event was captured.
WorkflowContext	interface	Execution facts available to every node of a running workflow.
WorkflowEvent	interface	Metadata only: never includes state, prompt, parameters, results or raw errors.
WorkflowExtension	interface	Additional nodes and routes merged into an existing definition.
WorkflowFailure	interface	Error retained only while entering a registered failure phase.
WorkflowGraph	interface	Pure registered topology; routes sharing a target share an edge within one kind.
WorkflowGraphEdge	interface	Completion has no target node; recovery edges remain distinct from normal edges.
WorkflowGraphNode	interface	Node metadata and derived incident edges, without executable callbacks.
WorkflowGraphRoute	interface	Declaration order is retained even when multiple routes share a topology edge.
WorkflowModel	interface	Model and tool access for one workflow invocation. Every call is charged to the workflow's shared budget. Overloads select the transport: a prepared call, the default plain-text transport, or one registered transport with its typed result.
WorkflowNode	type	One node of the graph.
WorkflowNodeReport	interface	Detail an App node reports about its current visit.
WorkflowRoute	type	One route out of a node. Routes are evaluated in array order and the first match wins. A route either continues at targetNodeId or completes the workflow through complete; declaring both is invalid.
WorkflowSubflowRecord	type	Historical subflow snapshots may omit recorder fields or descriptive content.

Shared contracts & helpers

Open group

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.

Models & interaction

Open group

Symbol	Kind	Purpose
AggregatedToolCall	interface	One completed native tool call in provider index order.
AsIntent	type	Demand-discovery metadata; it has no identity independent of its tool.
ChatProvider	class	Streaming model provider. Implementations must stop producing when context.signal aborts and should surface transport failures by rejecting the iteration rather than ending it silently.
createModelTransport	function	Compose a registered selection transport. The capability source may be a static catalog or a function of the stage id; the resulting definitions are captured when prepare runs and are used both to build the instruction and to reject unknown capability ids at finish time. requireStrictArguments is a registration-time assertion: a transport cannot demand strict arguments from an adapter that does not support them.
createToolCallCollector	function	Create a collector for one response.
FunctionCallDelta	interface	One streamed fragment of a function call; fragments with the same index must be joined.
IntentOptions	interface	Demand-facing hints attached to one Tool; no independent identity is created.
jsonObjectInteraction	constant
ModelAssistantToolMessage	type	Assistant turn that may declare tool calls and may carry an empty text body.
ModelCallRequest	type	One model call request. The input shape selects prompt mode or message mode.
ModelCallTrace	interface	Accumulated facts of one model call, reported on success and on failure.
ModelChildOptions	interface	Request-bound isolated runner settings; provider and ancestor budgets cannot be replaced.
ModelChildPolicy	interface	Request-wide limits, shared by every descendant. They cannot be enlarged by a child.
ModelFunction	interface	Provider-neutral function definition. Execution and authorization stay with the host.
ModelImage	interface	Model message primitives shared by every provider adapter. These shapes are deliberately provider-neutral: they describe text, optional images, streamed parts and the options a call may carry. Provider-specific wire formats stay in support/model. Exports: ModelImage, ModelMessage, ModelToolCall, ModelAssistantToolMessage, ModelToolResultMessage, ModelUsage, ModelFunction, FunctionCallDelta, ModelPart, ModelOptions.
ModelInputMeasurement	interface	Exact prepared-request accounting; token values exist only with an explicit model counter.
ModelInteractionAdapter	interface	Pluggable implementations all consume the same business registry. No automatic fallback.
ModelMessage	interface	One provider-neutral turn; images are user visual input and are not part of the text budget.
ModelOptions	interface	Per-call provider options; Core passes them through and does not normalize provider ranges.
ModelOutputEvent	type	Delivery sink, awaited in order. Parts are unvalidated proposals, never execution receipts.
ModelPart	type	One streamed response part: assistant text or a function-call fragment.
ModelPrepareRequest	interface	Transport selection for prepare; omitted fields take the runner defaults.
modelProtocolError	function	Throw a model protocol validation error.
ModelProviderContext	interface	Per-call facts a provider receives besides the messages themselves.
ModelResponseCollector	interface	Accumulates streamed parts for one call and resolves them into the transport's result.
ModelRunner	class	Execute registered model stages under one request's budgets and lifetime. Invariants: at most one call is in flight per runner; callCount and journal are local to the runner while totalCallCount includes descendants; every call is charged to the shared budget before I/O and every failure is annotated with its stage before it propagates. No business prompts, domain stages or provider SDKs are built into this runner.
modelRunnerDefaults	constant
ModelRunnerOptions	type	Full runner construction options: provider, transports, sinks and named limits.
ModelRunnerPorts	interface	Host ports a model runner needs in addition to its provider and transports.
ModelRunnerSettings	interface	Named settings keep all model limits together; output token reservation stays per call.
ModelRuntimeConfig	interface	Per-request model runtime limits.
ModelSelection	type	A model's chosen capability together with its parsed arguments.
ModelSessionCall	interface	One completed tool call in a session response.
ModelSessionResult	interface	Complete result of one session response.
ModelTokenBudget	interface	Provider-injected token accounting. Core never guesses a character-to-token conversion, so token budgets exist only when a host supplies a real counter.
ModelTool	interface	Common selectable model interface; resolution proposes a value without business execution.
ModelToolCall	interface	One tool call the assistant declared, in provider order.
ModelToolCatalog	type	A compiled entity catalog also supports the minimal stage source contract.
ModelToolRegistration	type	Registration form: input typing is erased, output typing is preserved.
ModelToolRegistry	class	A request/stage projection is a sealed registry. Hosts filter availability before projection.
ModelToolResultMessage	type	Tool result turn; toolCallId is required and images/tool declarations are rejected.
ModelToolSource	interface	Minimal source a stage needs: enumerate tools and resolve one selection.
ModelTransportDefinition	interface	One registered transport: a wire format prepared for a stage.
ModelTransportRegistration	interface	Binds an adapter to the tools one transport serves.
ModelUsage	interface	Provider-reported token counts for one call; used for accounting, never for admission.
NativeFunctionCall	interface	Request-local native call buffer; never an execution receipt.
nativeFunctionInteraction	constant
PreparedModelCall	interface	Request-bound, single-use transport snapshot. Repeated measurements do not prepare or spend calls.
PreparedModelInteraction	interface	Adapter output for one stage, before the caller binds capability resolution.
PreparedModelTransport	interface	Prepared transport handed to the runner, including sampling defaults.
RegisteredModelTool	type	Frozen snapshot stored by a registry after schema validation.
RegisteredTransportOutput	type	Result type of a transport selected by id. core:plain-text yields string, a registered id yields its declared result, and an id the runner does not know yields unknown rather than a guessed type.
retryMultipleModelCalls	function	Retry once when the failure is a rejected multi-call proposal. Only the MODEL_MULTIPLE_CALLS code is retried; every other failure is rethrown unchanged. The caller owns the fallback prompt and the budget it consumes.
ToolCallCollector	interface	Aggregation entry point for streamed function-call deltas.
ToolCallFailure	type	Report a protocol violation and stop; callers decide how the failure is classified.
ToolCondition	type	Activation is independent of participation in demand discovery.
ToolContext	type	Read-only host data without changing explicit any/unknown erasure into an object constraint.
ToolProposal	interface	A model proposal, not an authorization or execution receipt.

Context & journals

Open group

Symbol	Kind	Purpose
assembleContextPlan	function	Build the model input for a context plan.
assembleFragments	function	Build the model input from fragments. Metadata remains program-side: data never becomes a system instruction.
BuiltContext	interface	Assembled context plus the accounting needed to explain the budget decision.
ContextFragment	interface	One piece of model-visible input before assembly.
ContextFragmentUsage	interface	Accounting entry reported for one fragment that actually entered the context.
ContextJournal	class	Request-local context projection of execution receipts; not a separate persistent log store.
ContextLifetime	type	Declared validity window of a fragment's content.
ContextPlan	interface	Unassembled input; App-side nodes may process it before the Core budget boundary.
ContextRecord	type	One journal entry: a model call, a tool request or a tool result. The three variants are distinguished by type; value/input stay unknown because their domain meaning belongs to the App.
ContextTrust	type	Who produced the content, and therefore how much it may influence the model.
validateContextBudget	function	Enforce the character budget of the whole model input.
validateContextFragment	function	Validate one fragment and return the text it contributes to the model input.

Configuration, catalogs & policies

Open group

Symbol	Kind	Purpose
BreakCheck	interface	Each rule owns a semantic/readability group and its tags, independently of shared errors.
BreakEvent	interface	Diagnostic metadata only; rule inputs and request data are not included.
BreakPredicate	type	Each predicate is evaluated only after the preceding predicates passed.
BreakReason	type	Lazy reasons preserve error construction and message evaluation on the rejection path only.
breakWhile	function	Reject as soon as one of several conditions holds. Ordinary processing stays an ordinary if; this helper is for validation tables whose entries are evaluated in order and stop at the first failure. Behaviour that depends on earlier entries is expressed with a callback form. Reject when any predicate holds, reporting the given observer tags. Reject when any structured check holds. Each check may carry its own reason and tags; the first match stops the evaluation. Reject when a single value is truthy. Ordinary truthiness applies, so a function passed as a value counts as a failure; use the predicate form to evaluate it instead. Reject when a single value is truthy, reporting the given observer tags.
BreakWhileConfig	interface	Global rejection observer installed once per process.
matchRule	function	Dispatch to the first matching rule. A rule without a pattern matches unconditionally, so the table's order decides precedence. The first match owns the result even when its handler returns undefined, and later rules are not consulted.
MatchRule	interface	Order is priority. Patterns may inspect values, types, state or regular expressions.
WalkRule	interface	Synchronous traversal; local rules may omit catalog metadata.
walkRules	function	Walk every rule in order, mutating the shared input. Later rules observe the mutations of earlier ones, which is why traversal is strictly sequential and every participant must be synchronous. Throwing stops the walk immediately; remaining rules are skipped. Walk every rule in order, mutating the shared input.

Observation & diagnostics

Open group

Symbol	Kind	Purpose
CoreDiagnosticRecord	interface	Persisted data is untrusted: normalization checks the current envelope, not arbitrary payloads.
CoreEvent	type	A recorded Core fact. Every variant carries the same envelope: a version marker, unique event id, producing span's identity, a per-producer monotonic sequence, the occurrence instant and optional reported sub-steps. subStepsDropped/subStepsTruncated state that reported detail was bounded.
coreEventCatalog	constant
CoreEventDescriptor	interface	Event classification used when deciding whether a sink accepts an event. metadata events carry identity, timing and status only; content events may carry user, model or tool content and therefore require an explicit acceptance decision.
CoreEventName	type	Union of every Core event name; the key set of CoreEventPayloads.
CoreEventPayloads	interface	Payload of every Core event, keyed by event name. Fields are the event's own facts only.
CoreLogOutput	interface	Destination for recorded facts; implementations decide filtering and durability.
createDiagnostics	function	Configure the optional log consumer of the shared execution fact source.
CreateDiagnosticsOptions	interface	Options for creating a root diagnostic scope.
DebugStepsOutput	interface	Debug material a handler contributes to a diagnostic event.
DiagnosticContext	interface	Recording scope bound to one execution identity. A child scope inherits the sink and observer of its parent; only identity changes.
diagnosticError	function	Convert a thrown value into a plain record suitable as a log payload.
DiagnosticIdentity	interface	Execution identity only: never message, account or HTTP identity.
DiagnosticSpanFields	type	Identity fields a child span may override; the parent supplies run, span and parent span.
NodeReportingContext	interface	Reporting surface handed to a node or tool for the duration of one visit.
normalizeDiagnosticEvent	function	Validate a persisted diagnostic record and return a detached copy. Persisted data is untrusted, so the envelope version, event type, identity, ordering and the bounded sub-step shape are checked; the payload itself is not interpreted. The copy is deep cloned, so a store cannot hand back a record that later shares structure with the caller.
RecordedSubStep	interface	A step already accepted by a logger, carrying recorder-assigned bookkeeping fields.
ReportedStep	interface	One step as reported by a node; fields beyond identity are optional detail.
ReportedStepStatus	type	A status a node may report; derived from the catalog, never declared separately.
reportedStepStatusCatalog	constant
reportedStepStatuses	constant
ScopedSubFlowLogger	class	Non-inheriting delegate. Stores only the original logger and its bound subnode identity.
ScopedSubFlowStepInput	type	Scoped writes cannot supply or override the identity bound by their delegate.
SubFlowLog	interface	Common read/write surface for both independently implemented logger classes.
SubFlowLogger	class	Full execution-owned recorder. Owns its store and may issue restricted delegates.
SubFlowStepFix	interface	Explicit revision whitelist: identity, grouping and business type are never patchable.
SubFlowStepInput	interface	Input accepted by write; the logger assigns the step id and sequence.
SubFlowValue	type	JSON-like value accepted in reported payloads; depth and size are bounded by the recorder.
SubStepProgress	interface	Compact progress notification emitted for each accepted sub-step write or fix.

Tools & capabilities

Open group

Symbol	Kind	Purpose
ErasedTool	interface	Type-erased tool shape the registry executes after parsing at the boundary.
ExecutableTool	interface	One registered tool, typed by its input, output, host context and id literal.
executeInvocation	function	Run one synchronous invocation and record its effects.
InvocationHandler	interface	A named handler invoked by a tool lifecycle step.
RegisteredTool	type	Registered snapshot: public data is retained, implementation helpers are not a contract.
ToolDefinition	type	Configuration form; Support supplies the identity resolver when omitted.
ToolExecutionContext	interface	Execution facts handed to a tool for one invocation.
ToolExecutionEvent	interface	Fact emitted when one tool call settles, correlated by invocationId.
ToolInvocationPorts	interface	Optional tools the lifecycle resolves from the host context for one invocation.
ToolInvocationRequest	interface	One invocation request; the registry supplies signal and diagnostics when omitted.
ToolJournal	interface	Request-local execution receipts; the host decides their domain content.
ToolJournalFinish	interface	Closing record for one tool call, written once with the terminal outcome.
ToolJournalStart	interface	Opening record for one tool call, written before the handler runs.
ToolRegistry	class	Registry mechanism only: visibility, authorization policy, schemas and semantic metadata are host registrations. A registry is mutable until sealed and keeps its own call log.
ToolRegistryOptions	interface	Registry construction options.
ToolRegistryPorts	interface	Host ports a tool registry needs in addition to the tool definitions.

Support · Recommended implementations & strategies

Shared contracts & helpers

Open group

Symbol	Kind	Purpose
agent	function	Instantiate an Engine configuration class without creating an Engine, budget or request.
Agent	type	Original Engine configuration; union branches retain their required App/model relationships.
AgentOptions	type	Agent id is an external pool identity, not an override of Core branch or request identity.
agentPool	constant
AssociatedRegistration	interface	Owners retain their business fields; Support only reads model interface associations.
AssociationOptions	interface	Shared independent tools and a default projection from existing contracts.
AssociationSource	interface	Local provenance, never an extra model input requirement.
ClassDecoration	type
DecorationOptions	interface	Namespaces group external registration without changing Core options.
defineAssociatedCatalog	function	Compile independent and owner-derived Tool declarations, validating all references eagerly.
DefinitionReader	interface	Read-only roots. A typed read describes the expected contract, not a static id/type lookup.
fragment	function	Instantiate a self-describing fragment class; the original builder owns formatting checks. Bind a host's formatter method into an original fragment configuration.
Fragment	type	A formatter and its original provenance, trust and budget configuration.
fragmentPool	constant
IdentifiedDefinition	interface	Registration identity; ids are unique within one kind and namespace.
Intent	function	Mark a WorkflowTool for demand discovery; alone this decorator registers nothing.
MethodDecoration	type
model	function	Instantiate and validate model options without creating a Runner or consuming calls.
Model	type	Original Runner configuration; the decorator's pool id is not a model identity override.
ModelOptions	type	Model id is only a pool key; Core still owns the configured model/transport identities.
modelPool	constant
node	function	Instantiate a node definition class once, injecting its id; graph validation stays in Workflow. Bind a named host method as run without renaming or manually binding the original object.
Node	type	A node implementation; its public id is supplied by
nodePool	constant
Support	namespace
tool	function	Instantiate a tool definition class; schema and authorization stay with existing defineTool. Bind an existing host method as the tool's execute callback. A model-only tool method provides its synchronous resolver.
Tool	type	A tool implementation with the original schema, authorization and execution contracts.
ToolAssociation	type	Explicit tool references or inline overrides of the owner's default model interface.
toolPool	constant
workflow	function	Instantiate and validate workflow options, leaving actual execution with the original Engine.
Workflow	type	A complete graph definition whose workflow id is supplied by
workflowPool	constant

Tools & capabilities

Open group

Symbol	Kind	Purpose
CapabilityCatalogOptions	interface	Catalog construction options.
CapabilityModule	interface	Minimal composition contract; lifecycle and domain fields remain application-owned.
CapabilityToolReferences	interface	Tool references declared by one owner module.
CompiledTool	type	Tool definition type derived from a declaration literal, preserving input/output/id.
defineCapabilityCatalog	function	Build a frozen capability catalog from application module declarations. Each module must carry a non-empty description, and every contributed tool ID must be unique across modules. Reference projections run during construction and must be synchronous.
defineTool	function	Validate one tool declaration and freeze a detached copy of it. authorize must settle with void; a rejection has to be thrown, so a returned false cannot silently pass. Handlers are bound to the declaration object, and the input schema is re-snapshotted so later mutation cannot widen the accepted input.
defineToolCatalog	function	Infer the host context from existing executable definitions, without widening it to unknown. Explicit host typing remains available for contextually typed declaration lists.
SelectedTools	type	Catalog narrowed to the given ids: each kept tool's id literal is intersected with Id.
ToolCatalog	interface	Frozen tool catalog with model tools and per-request binding.
ToolCatalogEntry	type	Public declaration surface of one tool, without registry internals.
ToolModelView	interface	Model capability view of a tool catalog, retaining the host context type.
ToolOutput	type	Output type of the tool whose id matches Id; never for any other id.
ToolRuntime	interface	Catalog bound to one App request.
validateToolReferences	function	Validate tool references against the complete registered set. Checking against every registered tool (not only the ones available in the current request) keeps the declaration honest: a module may reference a tool that this request filters out, but never one that does not exist.

Models & interaction

Open group

Symbol	Kind	Purpose
chatCompletionFunctionOptions	function	Build the tool-selection request fields for a function-calling stage. The adapter expects exactly one function call per response, so tool use is required and parallel calls are disabled.
chatCompletionMessages	function	Map Core and provider messages to chat-completions message payloads. Only declared message fields are sent. Assistant tool declarations become nested tool_calls, and tool results become tool_call_id; both are rewritten explicitly rather than forwarded as-is. Messages with images become a content-block array; images are accepted only on user messages and only as http(s) or data:image URLs.
chatCompletionParts	function	Convert one streamed choice.delta into Core model parts. Text is emitted only when non-empty; each tool-call fragment carries its index so Core can reassemble arguments that arrive across chunks.
CompatibleModelConfig	interface	Configuration of one OpenAI-compatible endpoint.
CompatibleModelPorts	interface	Adapter ports the App may override without replacing the provider.
CompatibleModelProvider	class	HTTP/SSE lifecycle shared by hosts. Apps supply config and user-visible error mapping only. A static configuration is validated and frozen in the constructor. A configuration function is called once per request instead, so credentials and models may rotate between calls.
CompatibleModelProviderOptions	interface	Construction options for a compatible provider.
CompletionFailure	type	Build the classified failure a policy throws; the provider records it like its own failures.
CompletionPolicy	interface	Decision whether a finished stream satisfies the request.
completionPolicyCatalog	constant
CompletionRequestFacts	interface	Facts the provider reads from the request it actually sends. functions reports the Core call options and keeps the default policy equivalent to the behavior that existed before policies were configurable. toolChoice is the effective field of the serialized body, so a host override, or a field dropped for being undefined, is visible exactly as the upstream receives it.
CompletionSession	interface	Per-request completion state observed by one policy.
createJsonTransport	function	Create a typed JSON transport without a capability-selection envelope. The transport embeds the JSON Schema in the instruction and requires the response to be one complete JSON value. The returned response parser rejects native call events and invalid JSON, then validates the value through the supplied schema.
createModelStrategy	function	Compose runner options in precedence order: budget preset, selected model, declared reasoning, exact budget, then explicit Core fields. The result is validated through the same Core binding rules but creates no runner and spends no calls.
createProviderObservationScope	function	Bind provider observations to a caller-owned destination across diagnostic child spans. attach returns a scoped diagnostic context; contexts that were not attached through this scope produce no observations. Child contexts inherit the owner and a parent/child span path.
createReplyPreview	function	Create a model-output event handler that publishes preview bubbles. The handler resets on model.start, ignores other invocations, disables itself on unexpected output, and clears the preview when a call ends unsuccessfully. Rules are snapshotted at creation, and only explicitly registered prose fields are projected.
createReplyPreviewRules	function	Generate frozen preview rules from capability and stage declarations. Capabilities without preview metadata are skipped even when their stage opts in. Default paths are text and bubbles[*], each kept only when the capability schema declares it.
createSessionModelTransport	function	Create a session transport.
createStageModelTransport	function	Build a transport that projects a capability source through declared stage references.
createTextTransport	function	Create a plain-text transport that trims the assembled response.
defaultCompletionPolicy	constant
defineModelTools	function	Build a sealed capability catalog from typed declarations.
modelBudgetStrategies	constant
ModelBudgetStrategy	type	Preset name, or an explicit partial set of Core runner settings.
ModelChildrenOptions	interface	Group options: worker count, extra cancellation and accept/commit hooks.
ModelChildTask	interface	One child call in a group: its own limits plus the work to run with the child runner.
ModelChoiceIndex	interface	Minimal selector shape used while filtering the provider response choices.
modelInteractionCatalog	constant
ModelProviderErrorCode	type	Stable failure classification reported by the compatible provider adapter.
ModelProviderFailure	interface	Failure detail passed to the App's error factory.
ModelStageTransportRegistration	interface	Stage IDs and capability references are App-owned; this adapter only compiles their relation.
ModelStrategyOptions	type	Input of createModelStrategy: model selection, optional reasoning and budget plus explicit Core overrides. Explicit Core fields win over every generated value.
PreparedSessionTransport	interface	Prepared session transport handed to the runner.
prepareSessionFunctions	function	Build the session policy for one stage.
PreviewTool	interface	A model tool with an explicit, presentation-only streaming preview contract.
ProviderAssistantMessage	interface	Assistant turn; content may be empty when the turn is only a tool declaration.
ProviderErrorCapture	interface	Captured upstream error body and whether it had to be truncated.
ProviderEventDescriptor	interface	Provider event name plus its content class.
ProviderEventName	type	Union of provider event names.
ProviderEventPayloads	interface	Payload of each provider event. Content-bearing events are accepted explicitly.
ProviderMessage	type	Message list a host may pass to the compatible provider directly.
ProviderObservation	type	One observation: event name with its payload.
ProviderObserver	interface	The caller can correlate each observation using the original, request-local model options.
ProviderReasoningLevel	type	Supplier wire shape is explicit; levels express requested effort, not measured quality.
ProviderReasoningStrategy	type	How a reasoning level is translated into request fields. requestBody entries override generated fields, so a host can correct a provider that expects a different shape.
ProviderSystemMessage	interface	System instruction turn; text only, so the union rejects images and tool fields here.
ProviderToolCall	type	One tool call the assistant declared, in wire order; aliases the Core shape.
ProviderToolMessage	interface	Tool result answering one declared call.
ProviderUserMessage	interface	User turn; the only message type that may carry images, and never tool calls.
ReplyPreviewOptions	interface	Settings for createReplyPreview; sink receives every bubble list and is required.
ReplyPreviewRule	interface	One projection rule: which stage/capability it matches and which prose fields may be shown. A rule without toolId may only match a registered plain-text stage.
ReplyPreviewStage	interface	Stage declaration: which tools it exposes and whether it previews text or arguments.
ReplyPreviewTool	interface	Capability declaration used to derive preview rules. Omitted preview means the capability never previews, so previewing is an explicit opt-in.
ResolvedSessionCall	interface	One completed call with host-facing resolution; unknown tools and bad JSON stay non-fatal.
ResolvedSessionResult	interface	Complete result of one session response after host-facing resolution.
runChildren	function	Run child tasks concurrently and return their values in declaration order. The first failure aborts the remaining group, but an already in-flight commit is still awaited because cancellation does not mean the write was rolled back.
sessionCompletionPolicy	constant
SessionFunctionOptions	interface	Options a session transport may pass through to provider options.
SessionModelTransportRegistration	interface	Registration for one session transport.

Context & journals

Open group

Symbol	Kind	Purpose
ContextAssemblyOptions	interface	Assembly options for placement-based projections.
ContextBuilder	interface	Compiled builder. It holds no request state and may be shared across invocations.
ContextBuilderOptions	interface	Shared builder options.
ContextCompressionCall	interface	One compression request.
ContextCompressor	interface	Registered compressor handler.
ContextFragmentConfig	interface	Self-describing fragment declaration: metadata plus a formatter.
contextHandlerCalls	function
ContextHandlerReference	interface	Reference to a registered compressor or selector handler.
ContextHistoryGrouping	type	How a message history is split into groups for trimming.
contextHistoryStrategies	constant
ContextModelCall	interface	Same runner and same fixed invocation result as public model calls.
ContextModelRequest	interface	One model call made on behalf of a selector or compressor.
ContextNodeResult	interface	Outcome of one context node: the built input, its prepared model call and the change report.
ContextPolicy	type	Declared context policy for one stage.
contextPolicyCatalog	constant
ContextProcessingNodeDefinition	type	Definition accepted by createContextProcessingNode. It is a normal Core WorkflowNode except that the node body is declared here: plan builds the context, update decides the committed state, and policy/handlers/timeout are validated when the node is created.
ContextProcessingOptions	interface	Runtime inputs for one processing run.
ContextProcessingReport	interface	Facts recorded for one processing run.
ContextProjection	type	One declared projection: a single fragment or a placement expanded into fragments.
ContextRecentHistory	interface	Recent history that compression must keep verbatim.
ContextReduction	type	One declared reduction step.
contextReductionCatalog	constant
ContextReductionNodeDefinition	type	Definition of a reduction node: one registered step is applied per node run. stepId may be fixed or derived from state, which lets a graph route over several steps.
ContextSelection	type	Selection is independent of ownership; omitted selection preserves ordered execution.
ContextSelectionCall	interface	Everything a selector may inspect for one decision.
ContextSelectionCandidate	interface	Candidate step considered by selection, with its measured cost.
contextSelectionCatalog	constant
ContextSelectionNodeDefinition	type	Definition of a selection node: like a processing node, but update receives chosen step IDs.
ContextSelectionResult	interface	Selection stage result: the chosen step IDs plus the unchanged stage snapshot.
ContextSelector	interface	Model or local selector that chooses which reductions to apply.
ContextStageResult	interface	Result of a selection or reduction stage, before the node's update commits chosen fields.
ContextStrategy	interface	Validated inputs ready to pass to a context processing node.
ContextStrategyOptions	type	One history declaration that generates a step, or an explicit step list with optional history fields (fragment, field, preset, targetChars, keepGroups, grouping).
ContextStrategySettings	type	Shared reduce-policy settings applied to the whole strategy. Trigger and target fields follow the Core policy contract; omitted values fall back to the plan budget or to the trigger. Supplying steps disables generation and uses the explicit list.
ContextTokenMeasurement	interface	Injected token measurement for token-triggered policies.
createContextCompressor	function	Build a compressor that asks a model to rewrite one fragment. The request pairs a system instruction with a user message carrying the fragment ID, its current value and the target character count. Only the model's parsed value is returned; the caller decides whether the result fits the reduction contract.
createContextProcessingNode	function	Create one node that runs the complete context policy and returns the built context. Use this when the graph does not need to route between selection and reduction phases.
createContextReductionNode	function	Create a node that applies exactly one registered reduction step. Partial plans keep the full budget until final assembly, so intermediate nodes do not shrink the allowance reserved for the reply.
createContextSelectionNode	function	Create an ordinary node that selects reduction steps without executing them. The node reports the registered step IDs so the graph can route to reduction nodes itself.
createContextSelector	function	Build a selector that asks a model to pick reduction steps. Without a custom parser the model must answer with a JSON object containing a stepIds array; with a custom parser the application owns that contract but must still return step IDs.
createContextStrategy	function	Build a reduction policy from one or more history declarations. recent keeps a window of recent groups; continuity summarizes older groups while preserving the most recent originals. Neither preset claims semantic quality, only bounded input size.
defineContextAssembly	function	Compile ordered context projections into a builder. A projection is either a single fragment (with its own formatter) or a placement whose contribution handler expands to any number of fragments at request time.
defineContextFragments	function	Compile self-describing fragment declarations into a builder. Each definition carries its own trust, lifetime and size metadata, so no separate metadata catalog is needed. The budget may be a constant or a function of the request input.
processContext	function	Run a complete context policy in one call: snapshot, execute and finalize.
reservedContextCalls	function
selectContextSteps	function	Choose steps that fit the remaining call budget. Feasibility uses exact trim previews and declared call ceilings; the reply reserve and the selector's own allowance are subtracted before candidates are considered, so neither can be spent on reductions.
transformContextText	function	Apply a text transform to a fragment value, including strings nested inside objects. Structured values are walked through a JSON round trip, which is what the budget measurement serializes later; values that JSON cannot represent are therefore not preserved.
validateContextPolicy	function	Validate a complete context policy and every handler it can reference. Handler IDs must be unique and each handler must declare a non-negative integer call ceiling. Reduction targets and selection modes are checked by their own catalog entries.
validateContextSelection	function	Validate selector declarations and the selection mode they serve.

Configuration, catalogs & policies

Open group

Symbol	Kind	Purpose
defineRegistrationCatalog	function	Compile an ordered installation plan. Predicates observe the effects of preceding installations at request time; a predicate that throws rejects the install instead of being treated as false. Callbacks are bound to their declaring definition so implementations may rely on this.
defineSchema	function	Re-snapshot an existing adapter without changing its behavior. Used to detach a caller-owned adapter from later mutation before it is exposed or reused.
fromJsonSchema	function	Build an adapter from a caller-owned typed JSON Schema compiler. The schema is cloned and frozen before it reaches the compiler, so later mutation of the input cannot change validation. Compilation and validation must both be synchronous.
fromParserSchema	function	Wrap a library schema that already parses values (for example Zod or Valibot style). parse is delegated unchanged, so the library keeps ownership of coercion and error reporting; only the JSON Schema projection is produced here.
JsonSchemaOptions	interface	Options for building an adapter from a JSON Schema compiler.
JsonSchemaValidator	interface	App-owned JSON Schema compilers provide synchronous validation.
RegistrationDefinition	interface	One install step.

Transport & streaming

Open group

Symbol	Kind	Purpose
encodeSseEvent	function	Encode one event in the server-sent events wire format. Every line of data gets its own data: field, because a raw newline would start a new field.
JsonFrameLimits	interface	Bounds applied while scanning a streamed text.
JsonTransportPart	type	One scanned span: a complete object frame or a character outside any frame.
parseJsonFrames	function	Parse complete object frames under explicit count and size limits. Only whitespace may appear outside frames; a stray closing brace is tolerated only up to maxExtraClosings, which covers transports that repeat the delimiter after the payload.
scanJsonObjectFrames	function	Extract complete object-shaped spans from surrounding text, without parsing or selecting them.
SseOutputEvent	interface	One outbound event before wire encoding.
SseWriter	interface	Destination that reports backpressure instead of buffering without bound.
writeSseFrame	function	Write one encoded frame and wait for drain when the writer reports backpressure. The signal is re-checked around the write and the drain wait, so cancellation does not leave a pending write considered successful.

Observation & diagnostics

Open group

Symbol	Kind	Purpose
streamEvents	function	Bridge a push-style producer to a pull-style async iterable with a one-slot rendezvous. The producer must await every emit call before emitting again; concurrent emissions are rejected rather than buffered. The slot is released only after the consumer receives the event, so backpressure is exact.

Kit · Optional business libraries

Configuration, catalogs & policies

Open group

Symbol	Kind	Purpose
AgentCatalogPorts	interface	Ports the catalog reads from the App's registries.
CatalogGoal	interface	Goal as the catalog sees it: an id plus its declared delegates.
CatalogScope	interface	Scope as the catalog sees it: an id plus the tools it may use.
CatalogTask	interface	The goal currently accepted for the request, used to narrow the catalog.
CatalogTool	interface	Tool facts the catalog needs, independent of lifecycle details.
defineAgentCatalog	function	Compile a catalog projection over the App's live registries. The actual registries determine availability and relationships. No parallel capability list exists: goalIds filters by tool support, modelCatalog narrows to the currently accepted task when restrictToTask is enabled, and scope tool ids are filtered to tools that exist.
definePolicySet	function	Compile a policy set that reports every matching reason. Collect every matching reason; a configured mode cannot silently override a mandatory policy. assess returns the matched ids and deduplicated kinds rather than a single verdict, so callers keep the ordering information they need for messages and diagnostics.
defineRecoveryChain	function	Compile an ordered recovery chain. A handler reports whether it handled the input; handled undefined values remain explicit. The first handler that reports handled ends the walk, so declaration order is the precedence, and { handled: false } is the only way to fall through.
DescribedTool	interface	Model- or host-facing description of one tool.
Policies	constant
PolicyAssessment	interface	Result of assessing every registered policy against one input.
PolicyDefinition	interface	One declarative policy.
RecoveryDefinition	interface	One recovery handler in an ordered chain.
RecoveryResult	type	Outcome of one recovery handler, or of the whole chain.

Branches & versioning

Open group

Symbol	Kind	Purpose
AgentFamily	interface	Compiled family API. Every mutation returns the record after the write.
defineAgentFamily	function	Compile a versioned family backed by an App-owned compare-and-swap store. Every mutation reads the record, verifies the caller's expected revision, then commits with a compare-and-swap, so concurrent writers fail with a revision conflict rather than overwriting each other. Reads are also treated as policy checks because the App binds its read rules into the store it supplies.
Family	constant
FamilyDefinition	interface	App-owned hooks and limits for one family.
FamilyOperation	type	One of the four family mutations.
familyOperations	constant
FamilyRecord	interface	A whole family: its versions and which version is currently active.
FamilyStore	interface	CAS must cover every writer and the active pointer in one real storage commit.
FamilyVersion	interface	Immutable snapshot of App state at one point on a branch.

Observation & diagnostics

Open group

Symbol	Kind	Purpose
AgentOutputEvent	type	One output event of a delivered reply.
publishReplyEvents	function	Stream one reply as paced text chunks and bubble separators. Publish a validated reply without exposing its internal boundary to consumers. The pacing options are upper bounds, not exact timings: the pause and interval are clamped against maxDurationMs, so added delay never exceeds the budget while every chunk is still emitted.
REPLY_BUBBLE_BOUNDARY	constant
ReplyBubbleInput	interface	Reply pieces accepted by the bubble helpers; non-string entries are ignored.
replyBubbleTexts	function	Collect the non-empty-text parts of a reply.
ReplyDeliveryOptions	interface	Host-controlled delivery of already validated text; not upstream model generation.
serializeOutputEvents	function	Serialize the event protocol for callers using a text stream. preview events are dropped because they are not final text; bubbles become the boundary character again, so a consumer can re-split the stream.
textOutputEvents	function	Wrap already-chunked text as text events.

Shared contracts & helpers

Open group

Symbol	Kind	Purpose
Aggregation	constant
Candidates	constant
CandidateSelectionDefinition	interface	Declares the alternative-proposal envelope. A value without the declared field is treated as a single implicit candidate.
ContentProjection	interface	Projection output.
ContentProjectionOptions	interface	Candidate strategy for content projection.
createIntentRegistry	function	Create and seal a complete catalog; use the constructor for incremental installation.
defineCandidateSelection	function	Compile an alternative-proposal envelope contract. Alternative proposals are bounded and shallow; accepting a task closes this capability. A value that is not an object, or that does not carry the candidate field, is treated as a single implicit candidate and returned as-is. Once the envelope is present it must contain only that field, and its array must hold between minCandidates (default 1) and maxCandidates distinct candidate objects that do not themselves repeat the field.
defineContentProjection	function	Compile a JSON-preserving projector. Keep valid JSON while reducing prose before dropping records; budgets are caller policy. The candidate list is tried in order (outer counts, inner lengths), so callers control whether trimming text or dropping items is preferred, and the configured fallback is used only when no candidate fits.
defineDelivery	function	Compile a delivery pipeline from its declared stages. Stages are registered once, in declaration order, and must have unique non-blank ids. A stage without a handle is a named hook only, so beforeStage can observe it.
defineNormalization	function	Compile an ordered normalization pipeline. Steps run in declaration order. Each step may be skipped by its when predicate, receives the value produced by the previous step, and isComplete can stop the walk early, so the usual contract is "first completion wins" rather than "always run everything".
defineQueryAggregation	function	Compile one ordered read plan over a list of inputs. Ordered synchronous queries with optional stable-key merging; each real read stays host-owned. Inputs run sequentially in the given order, so a host can rely on a deterministic visit sequence. Without key every item is kept; with key the last write wins per key but the position of the first occurrence is retained.
defineTextSkillLoader	function	Compile a loader that validates registrations and reads their documents. The default contract is narrow by design: ids are lower-case words joined by hyphens (up to maxIdChars, default 64), each entry lives at <id>/SKILL.md, the kind is text-workflow, and the document starts with name/description front matter.
defineTreeProjection	function	Compile a depth-limited tree transform. Traverse synchronously in property/array order; only undefined omits a result. Because a visitor returns a new value instead of mutating, an omitted branch disappears from arrays and objects the same way, and maxDepth bounds both cycles and cost.
Delivery	constant
DeliveryOptions	interface	Pipeline construction options.
DeliveryStage	interface	One pipeline stage, identified for reporting and optional observation.
IntentDescription	type	Registered domain Tool with its delegates widened to the definition's delegate literals.
IntentId	type	Union of the ids of a definition set, or string when it cannot be narrowed.
IntentPolicy	interface	Registration rules for one intent registry.
IntentRegistry	class	Goal semantics and allowed values are configuration; the registry owns their common lifecycle. Registration order is preserved by ids, definitions, values and entries; once seal() is called the set is final and further registration is rejected.
IntentTool	interface	One domain Tool.
IntentToolRegistration	type	Configuration form; object arguments and a Tool proposal are the registration defaults.
mergeByKey	function	Merge duplicates without moving their first position; selection policy remains host-owned. The first occurrence of a key fixes the output position; select decides which item that position finally holds, so callers can prefer the newest or the most complete duplicate.
ModelBinding	interface	App-defined I/O. Registered literal IDs determine input and output types.
ModelCalls	class	Frozen catalog of model bindings plus a checked invocation entry point. Registration happens once in the constructor; the catalog is never mutated afterwards, so a caller cannot swap a provider in the middle of a run.
ModelInvocationContext	interface	One take consumes one binding invocation attempt, independent of batch size or chat tokens.
ModelInvocationRequest	interface	One model call: registered binding id, the input to hand over and its timeout.
Normalization	constant
NormalizationOptions	interface	Pipeline options.
NormalizationStep	interface	One ordered transformation.
projectContinuousExcerpt	function	Project a continuous excerpt of a body by binary-searching the longest prefix that fits. Binary-search a continuous prefix and keep an existing surrogate pair intact. render receives the prefix length, not the text, so the caller decides how the excerpt is framed.
Projection	constant
QueryAggregationOptions	interface	Query aggregation contract: several ordered reads collapsed into one item list. Place in the package: an optional App-side helper for merging results of the same query shape run against several inputs. The Kit owns ordering and optional stable-key merging; every real read, the merge policy and the meaning of an item stay with the App. Exports: QueryAggregationOptions.
RegisteredIntent	type	Frozen registration view: list fields are frozen copies, helper methods are dropped.
splitTextBlocks	function	Split long plain text on structural boundaries. Headings and horizontal rules start a new block, blank lines end the current one, and all other lines break only when the target size would be exceeded. A single line longer than the target becomes its own block so that paging can cut it into fragments later without splitting the line into unrelated sections. Concatenating every block reproduces the input exactly: no truncation, padding or dropped whitespace. The input must be plain text; binaries and rich documents are read elsewhere.
TextBlock	interface	One structure-aware block of a long text.
TextBlockOptions	interface	Splitting options.
TextBlocks	constant
TextSkill	interface	Loaded skill: registration plus the parsed document text.
TextSkillHeader	interface	Header every skill document must carry.
TextSkillLoader	interface	Compiled loader.
TextSkillLoaderDefinition	interface	Loader limits, parsing hooks and rejection wording.
TextSkillReadPorts	interface	Host port that reads one skill document by path.
TextSkillRegistration	interface	Catalog entry of one text skill, before its document is read.
TextSkills	constant
TreeProjectionOptions	interface	Depth- and record-level traversal options for tree projection.
uniqueBy	function	Stable deduplication preserves the original values; the host chooses equivalence. The first occurrence of each key wins and the input order is kept, so callers can rely on deduplication never reordering their list.

Knowledge, answering & presentation

Open group

Symbol	Kind	Purpose
AnswerCheck	interface	Result of one local or review check over a generated answer.
AnswerChecker	interface	One named check applied to a generated answer value.
AnswerFlowDefinition	interface	Static handlers and limits; signal, diagnostics and App dependencies arrive at run.
Answering	constant
AnswerIssue	interface	Validation problem produced while checking a generated answer.
AnswerItem	interface	One unit an answer batch must produce.
AnswerReader	interface	App-owned reader that gathers evidence for one task.
AnswerResult	interface	Final outcome for one item.
AnswerTaskDefinition	interface	Static binding of one answerable task.
AnswerTaskPorts	interface	Registries a task catalog validates its references against.
CompiledReplyFormat	interface	A resolved format with its checks bound; callers only inspect replies using it.
defineAnswerCheckCatalog	function	Compile a checker catalog. A checker may return a replacement value; it is threaded into the next checker, so the selected ids behave like an ordered chain rather than independent assertions.
defineAnswerFlow	function	Compile a reusable answer workflow. Reusable answer workflow. Requests own cells and repair budgets; models remain caller-owned. The flow runs at most maxRepairs + 1 rounds: one generation pass, then one repair round per failing item set, and finally an explicit accepted/fallback/blocked result per item.
defineAnswerReaderCatalog	function	Compile a reader catalog.
defineAnswerTaskCatalog	function	Compile the answer task catalog from its declarations and shared ports. Task ids, schemas, readers, outputs and checks have one compiled authority: a task can only reference a reader or check that the ports actually registered, and metadata is cloned and frozen so later mutation by the caller cannot change a registered task.
defineKnowledgeCatalog	function	Compile a knowledge catalog from document declarations. Reads are declarative: document returns the whole text, self returns exactly the named sections and subtree includes their nested sections. Section ids are validated up front, so a typo fails at read time instead of silently returning partial content.
defineKnowledgePublication	function	Compile a publication lifecycle over one App-owned atomic record. Candidate preparation and publication share the same compiler and an App-owned atomic revision. propose compiles and validates a candidate but leaves published documents alone; publish re-verifies sources and the base revision before swapping, so a stale candidate can never overwrite newer content.
defineOutputCatalog	function	Compile output definitions into one catalog. Compilation is where most mistakes surface: group membership is checked for cycles, master templates must have exactly one slot per field, and every bound/semantic field must name a registered provider. Composition then trusts the compiled catalog.
defineReplyFormats	function	Compile reply formats so that checks run only for templates the current turn uses.
defineSemanticSlots	function	Models select public semantic keys; hosts retain private values and selection policy. A text is valid when it uses at most maxOccurrences namespaced slots, every name is a declared key, and no malformed {{namespace remnant is left behind — the last check stops partial or misspelled placeholders from reaching the template engine.
defineTextTemplate	function	The program owns the master; inserted model text is a value and is substituted once only. Substitution is single-pass String.replace: a value that itself contains {{slot}} is left as literal text, so a slot value cannot inject further substitutions.
Knowledge	constant
KnowledgeCandidate	interface	A proposed document awaiting publish or reject.
KnowledgeCatalog	interface	Compiled catalog of knowledge documents.
KnowledgeCatalogOptions	interface	Catalog construction options.
KnowledgeDocument	interface	One versioned document as supplied by the App.
KnowledgePart	type	Document content: a text leaf or a nested section.
KnowledgePublication	interface	Compiled publication workflow.
knowledgePublicationOperations	constant
KnowledgePublicationOptions	interface	App-owned guards, store and limits for a publication workflow.
KnowledgePublicationRecord	interface	Stored publication state: one published revision plus pending candidates.
KnowledgePublicationStore	interface	Single-writer store for the publication record.
KnowledgeRead	interface	A request for one document selection.
KnowledgeSection	interface	A named section that may contain text and further sections.
KnowledgeSnapshot	interface	Materialized read result.
KnowledgeSourceReference	interface	Citation of the material a candidate was derived from.
mergeReplyBubbles	function	Normalize a reply that has no declared format: drop blank bubbles and merge overflow into the last allowed one. Text content is preserved.
OutputCatalogOptions	interface	Catalog construction options.
OutputComposeInput	interface	Input for composing one output: model values plus program-assigned group members.
OutputDefinition	interface	One output shape.
OutputField	interface	One field of an output definition.
OutputIssue	interface	Output problem with a guaranteed field path.
OutputProvider	interface	App-owned value provider for bound and semantic fields.
OutputResult	interface	Composed output value.
parseKnowledgeDocument	function	Paired, nestable anchors are one text adapter. Other sources supply the same document contract directly.
Presentation	constant
ReplyFormatCheck	interface	One check a template declares, evaluated against the rendered bubbles.
replyFormatChecks	constant
ReplyFormatDefinition	interface	A template-bound reply format, matched against per-turn facts.
ReplyFormatOptions	interface	Declaration input for defineReplyFormats.
resolvePreference	function	Resolve the preferred candidate. Highest priority wins; order breaks ties with the later entry first, so recency can be encoded without touching priority. The input array is copied before sorting.
SectionSelection	type	Which part of a document a read returns.
selectVariant	function	Pick one variant, avoiding an immediate repeat when alternatives exist. When every candidate equals previous, the full list is used again, so a single-value set still yields a result instead of failing.
SemanticSlotDefinition	interface	Declares the {{namespace:key}} slots a model may use, and how often.
TextTemplateOptions	interface	Text template construction options.
validateAnswerBatch	function	Validate that one batch is well formed and fully covered.

Artifacts & recovery

Open group

Symbol	Kind	Purpose
ArtifactReference	interface	References locate artifacts; only the App resolver establishes access and current validity.
ArtifactResolver	interface	App-registered resolver that turns a reference into an App value.
Artifacts	constant
defineArtifactCatalog	function	Compile a catalog of artifact resolvers plus a checked resolve entry point.
defineDurableTask	function	Compile a durable task definition into a resumable runner. Each run call locks the task id in the store, loads the checkpoint and resumes at nextStepIndex. A checkpoint from another definition id or revision, or one that fails the predicates below, is rejected instead of being repaired, because silently accepting it would replay App side effects under a different contract.
Durable	constant
DurableCheckpoint	interface	Persisted task progress; the only state a resume reads back.
durableReplayPolicies	constant
durableStatuses	constant
DurableStep	interface	One step of a durable task.
DurableStepContext	interface	Execution facts handed to a durable step.
DurableStore	interface	App implements an exclusive lock across every writer and validates/serializes stored state.
DurableTask	interface	Compiled task: resumes from the store and returns the final state.
DurableTaskDefinition	interface	Task definition, including the App hooks that guard every resume.
DurableTaskOptions	interface	Runtime options for a compiled durable task.

Models & interaction

Open group

Symbol	Kind	Purpose
bindInteraction	function	Bind every registered transfer command to a local handler. Models cannot add handlers.
Command	interface	Compiled command.
CommandCatalog	class	Mode and cross-protocol field ownership checks are shared by all receiving hosts. The catalog seals itself as soon as construction finishes, so a run cannot register a new command later; set remains available only for the superclass installation pass.
CommandCatalogOptions	interface	Envelope-level options for a command catalog.
CommandDefinition	interface	Declarative command shape before compilation.
commandSchema	function	Build a JSON schema for one command id. Prefer compiled schemas; retain the existing open-schema contract for dynamic host protocols. A protocol without fieldSchemas falls back to an open object that only pins the discriminator, which keeps legacy hosts working without weakening compiled ones.
compileCommands	function	Compile a whole catalog with shared envelope fields. Applications declare only their own data and handlers. Defaults are merged in this order: unrelated default keys, then the command's own keys, with fields, checks and tags concatenated so shared envelope checks always run before per-command checks.
defineCommand	function	Compile declarations once. Parsing is synchronous and never executes a registered tool. Two schemas are produced from one declaration: modelJsonSchema marks only fields the model must fill, while inputJsonSchema marks every required field. A discriminator, when present, is prepended as a required constant field.
defineCommandCatalog	function	Compile definitions and wrap them in a sealed catalog.
defineInteractionProtocol	function	Construct a protocol from one definition.
INTERACTION_CATEGORIES	constant
InteractionCategory	type	Interaction purpose, never an authorization level or an assertion of execution success.
InteractionDescriptor	interface	Catalog metadata for one command, independent of its field shape.
InteractionHandlers	type	Handler map keyed by command id; each handler receives the parsed value and App context.
InteractionProtocol	class	Web/AI payload family. HTTP/SSE framing and actual command execution remain separate ports. Every command registered here gets the envelope's discriminator forced to its own id, so a payload cannot claim one command while carrying another command's data.
InteractionProtocolDefinition	type	Transfer envelope plus its registered command family; no change to HTTP or SSE framing.
ProtocolCheck	interface	One declarative rejection rule.
ProtocolField	interface	Field presence, schema and ownership are declared together; schemas describe model input.
ProtocolPredicate	type	Predicate evaluated during validation; any truthy result counts as a failure.
ProtocolReason	type	Lazy rejection wording: a fixed message, a pre-built error, or a factory bound to the value.
ProtocolShape	interface	Custom protocols may derive dynamic keys without supplying a compiled schema.
RegisteredProtocol	interface	Runtime extension contract; hosts retain their own version values and validation context.

MockGPT · Mock models & debugging

Open group

Symbol	Kind	Purpose
CallRecord	interface	Detached snapshot of one accepted call, exposed through MockGPT.records.
createMockHandler	function	Create a bare Node request listener backed by the mock.
createMockServer	function	Create a self-contained mock HTTP server with explicit listen/close control. No UI or static assets are served: only the model routes answer, everything else is a 404.
encodeModelResponse	function	Optional app-owned codec; validation and encoding consume the same snapshots. Thin public wrapper over encodeModel: re-validates identity arguments and re-snapshots both the request and the model output, so callers that build replies themselves get identical validation and cannot mutate the mock's state afterwards.
Generated	type	What a rule may produce: plain data, or a descriptor that changes transport behaviour.
GenerationContext	interface	Everything a rule or generator may read for one accepted call. The context is frozen; the only mutable side channel is report, and only while the call is still pending.
GenerationInput	interface	Input of MockGPT.generate. Normalized exactly like an HTTP request body, so a rule matches identically through both entry points; only model and messages are required.
GenerationOptions	interface	Per-call options of MockGPT.generate.
Generator	type	A rule's output: either a fixed value (deep-copied and frozen when the instance is built) or a function evaluated per call. A function may be async and is awaited under cancellation.
generatorNames	constant
generators	constant
HandlerOptions	interface	Options shared by the standalone server and the bare request handler.
HttpFault	interface	A simulated HTTP-level failure returned instead of a model reply.
isPublicAddress	function	Decide whether an address is an acceptable public destination.
JsonValue	type	Any value accepted by the package's JSON snapshot rules: strings, finite numbers, booleans, null, arrays and plain objects.
LoadedPage	interface	A fetched page body plus the metadata needed for decoding and diagnostics.
Message	type	One entry of an OpenAI chat conversation. The runtime validates role against the OpenAI role set and validates the outer shape of content; every other field is retained verbatim so vendor extensions flow through.
MockGPT	class	Configurable mock model instance. Create one per test or per mock server.
MockGPTError	class	Error type carrying a stable machine-readable code plus optional HTTP status and details. The HTTP adapter maps status onto the response and serializes code/details into the OpenAI-style error body, so codes are part of the public contract.
MockGPTOptions	interface	Construction options of a MockGPT instance.
ModelOutput	interface	The model-authored part of a reply, before it becomes JSON or SSE frames.
ModelRequest	interface	A normalized /chat/completions request, produced by snapshotRequest. Optional undefined fields have already been dropped and stream is already defaulted, so rules always observe the same shape regardless of whether the caller used generate or the injected fetch.
OutputOptions	interface	Transport-level knobs of a generated response. All values are simulated: they affect framing and timing of the mock reply, not real model behaviour.
ResponseDescription	class	Wrapper that distinguishes a transport instruction from ordinary generator data. kind: 'model' carries a ModelOutput, 'http' an HttpFault response, and 'reject' a message used to simulate a network failure. Instances are recognized by brand rather than by instanceof alone, so descriptors survive crossing the ESM/CJS boundary.
responses	constant
routes	constant
Rule	interface	One ordered matching rule of a MockGPT instance.
ServerOptions	interface	Options of createMockServer, adding shutdown behaviour.
sources	constant
TextOptions	interface	Common options of the text generators.
TextSource	type	Text supplied to a text generator. A function may be async; it receives the per-call context so a source can depend on the prompt or on the call index.
ToolCall	interface	A tool call the mocked assistant emits instead of executing.
Usage	interface	Token accounting reported by the OpenAI API; validated for internal consistency.
WebOptions	interface	Configuration of sources.web.
WebProfile	type	Name of an entry in webHeaderProfiles.

Intents & scopes

Open group

Symbol	Kind	Purpose
createScopeRegistry	function	Create and seal a complete catalog; use the constructor for incremental installation.
RegisteredScope	type	Frozen registration view: every list is a frozen copy, evidence entries are projected.
RegisteredScopeEvidence	type	Registered evidence entry: public data only, frozen by the registry.
ScopeDefinition	interface	One declarable scope. Ids and aliases share one namespace and must be unique.
ScopeDescription	type	Plain description with mutable arrays, for documentation and model-facing catalogs.
ScopeRegistry	class	Generic scope relationships; categories, intent policy and extra fields belong to the host. A scope is addressable by its id or by any of its aliases; aliases resolve to the declaring scope, and a name may be claimed only once across both namespaces.
ScopeRegistryPolicy	interface	Registration rules for one scope registry.

Retrieval & evidence

Open group

Symbol	Kind	Purpose
defineEvidenceChecklist	function	Compile a reusable completion checklist over actual observations. A requirement is satisfied when at least one observation satisfies the provider registered for its kind; isComplete requires every requirement to be satisfied, and missing returns those that are not. Hosts define evidence semantics.
defineEvidenceProjection	function	Compile a projection that keeps only the sources a caller asked to see. No selection retains the complete evidence; a selection narrows registered source-bearing results. Observations whose tool has no provider pass through untouched, so the projection can only ever remove sources it knows how to name.
defineRetrieval	function	Compile a retrieval runner from its declared ports and effects. Rejected queries stay in the caller's seen set, so a retry is reported as a duplicate instead of silently repeating the adapter call; only successful results increment the query count.
Evidence	constant
EvidenceProjectionDefinition	interface	Projection configuration, keyed by the tool that produced an observation.
EvidenceProjectionProvider	interface	Describes which sources an observation can cite, and how to narrow it to cited ones.
EvidenceProvider	interface	Adjudicates one evidence kind against real observations.
EvidenceRequirement	interface	Requirements describe evidence that must already exist, never a model's assertion of success.
FusedRank	interface	One fused result with the per-source ranks that produced its score.
RankedList	interface	One retriever's ordered result, optionally weighted.
reciprocalRankFusion	function	Fuse ranked lists with one-based reciprocal rank fusion. Raw retriever scores are intentionally not mixed. Ties break on id, so the output is deterministic for a given input.
Retrieval	constant
RetrievalDefinition	type	Retrieval ports specialized to an App operation context.
RetrievalEffect	interface	One effect applied after a successful query, in declaration order.
RetrievalPorts	interface	Host ports and policy for one retrieval kind.
RetrievalReason	type	Lazy rejection wording: a fixed message, a pre-built error, or a factory bound to the query.
RetrievalReceipt	interface	Facts of one accepted query.
RetrievalResult	interface	Adapter output for one accepted query; the Kit renames each source before returning it.
RetrievalRunner	interface	Compiled retrieval runner.
RetrievalSource	interface	Request-local citation reference; the App may separately carry its content entity id.
RetrievalState	interface	Request-owned state. Clearing current evidence must not replenish spent budgets or seen keys.
TextSearch	class	Optional App-side full-text index. No storage, identity, model calls or Core dependencies. Only declared fields are indexed and only storedFields come back with a hit, so a document never leaks extra properties into search results.
TextSearchHit	interface	One ranked match; terms are post-tokenization and only stored fields are returned.
TextSearchOptions	interface	App supplies fields, tokenizer and its own schema/tokenizer revision.
TextSearchQuery	interface	Search input: a hard result limit and an App-owned filter, both required on every query.
TextSearchSnapshot	interface	Serialized index; the revision pair proves the snapshot matches the current configuration.
VectorSearch	class	Exact cosine search for a bounded embedded corpus. Identity and metadata are App-owned. Vectors arrive as plain arrays and are stored normalized in Float32Array form, so query time only needs a dot product per candidate.
VectorSearchHit	interface	One search hit; the document is a cloned snapshot, not the indexed instance.
VectorSearchQuery	interface	Search options excluding the query vector, which search takes alongside them.
VectorSearchSpace	interface	Embedding space identity and width; vectors from another space must never be mixed in.

Log review & evidence reports

Open group

Symbol	Kind	Purpose
defineReflection	function	Compile a reflection task. Model-driven investigation through ordinary registered tools and the existing Core loop. The task always reports persisted: false: storing a report is the App's decision. Observed findings must cite evidence ids that were actually returned in this run, which is what keeps the report tied to real observations instead of model recall.
defineReflectionLogSource	function	Build a reflection source over a log reader. Coverage is reported as best-effort: a page is only complete when the reader exhausted the run without capture gaps or omitted issues, and every gap or issue code is surfaced instead of being silently dropped.
Reflection	constant
ReflectionDefinition	interface	Configuration for compiling a reflection task.
ReflectionEvidence	interface	Explicit metadata projection, not an arbitrary original event/payload.
ReflectionFinding	interface	One finding, always tied to the evidence it rests on.
reflectionFindingKinds	constant
reflectionIdentityFields	constant
ReflectionLogReader	interface	Structural port: the App supplies its own FileLogReader, trusted scope and current authorization.
ReflectionPage	interface	One page of evidence plus an honest statement of its coverage.
ReflectionQuery	interface	One evidence query.
ReflectionReport	interface	Request-local reflection result.
ReflectionSource	interface	App-owned evidence source, including its own authorization.
ReflectionTask	interface	Compiled reflection task.

Tools & capabilities

Open group

Symbol	Kind	Purpose
LifecycleHooks	interface	Everything one tool declares for a request. Declaring id turns the tool into an invocation owner, so protocol and call become required in practice; the registry rejects a partial declaration. Every other hook is optional and returning nothing expresses "no opinion".
LifecycleProtocol	interface	Output protocol carried by a tool lifecycle.
Policy	interface	Registration policy shared by every tool in the registry.
RegisteredToolDefinition	type	Registered snapshot with frozen goal ids and projected hooks.
Tool	interface	A registered tool: model metadata plus one optional lifecycle block.
ToolFinalizer	type	Converts an executed decision into the tool result; must be synchronous.
ToolLifecycleRegistry	class	Registry of tools whose lifecycle, protocols and context contributions the App declares. Registration is only possible before seal(); afterwards the catalog is read-only, so a run cannot change which tools exist. Every hook is optional and is applied in registration order, which is why registerAll preserves iteration order.
ToolModelField	interface	One model-context field contributed by a tool.
ToolNormalizer	type	Converts untrusted input into a decision; must be synchronous.
ToolProtocol	type	Protocol type of a tool's lifecycle invocation.
ToolRegistration	type	Declaration form; the registry derives the ModelTool projection from existing handlers.
ToolRuntimeTypes	interface	One schema binds lifecycle handler types without introducing platform fields into core.
ToolsOptions	interface	Construction options for a tool registry.