Rulvar API reference

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Rulvar API reference / @rulvar/anthropic / mapAnthropicStream

Function: mapAnthropicStream()

function mapAnthropicStream(
   stream, 
   ids, 
options?): AsyncGenerator<ChatEvent, TurnMapping>;

Defined in: packages/anthropic/src/wire.ts:474

Maps one Messages API stream into ChatEvents, yielding each canonical event AS the corresponding provider event is consumed: the consumer's pull drives the provider read (natural backpressure, no buffering, no detached work). The generator's RETURN value carries the accumulated turn state the adapter needs for pause_turn continuation. Yields an early usage event from message_start (the input side is known immediately) and exactly one terminal finish when the stream reaches message_stop. A stream that pauses (pause_turn) or ends before message_stop yields NO terminal event of its own: the return value's pauseTurn and finished flags report which case happened, and the anthropic() adapter turns a truncated read (finished false without a pause) into the retryable transport error the contract requires, so a direct mapper consumer must check the flags rather than wait for an error event. carryRetained holds thinking blocks from earlier pause_turn continuations of the same turn so the terminal finish ships the whole turn's retention payload (M4-T02).

Parameters

Parameter	Type	Description
stream	AsyncIterable<AnthropicStreamEvent>	-
ids	IdMap	-
options?	{ carryRetained?: Block[]; usagePrior?: Usage; wirePrior?: { responseIds: (string | undefined)[]; }; }	-
options.carryRetained?	Block[]	-
options.usagePrior?	Usage	Accumulated usage of the PRIOR pause_turn segments of this turn (RV1003): the terminal finish must speak for the WHOLE logical turn, because core sums the per-segment mid-stream reports and verifies them against the finish total; a finish carrying only the last segment's counts turns a legitimate absorption into a usage-invariant kill and loses the paid segments from the money. Absent on the first segment, so an unsegmented finish stays byte-identical.
options.wirePrior?	{ responseIds: (string | undefined)[]; }	Response ids of the PRIOR pause_turn segments of this turn (RV905): when present, the finish metadata names the whole wire request set (wireRequests: { count, responseIds }) so the core can account the dispatch at its true wire count. Absent on the first segment, so an unsegmented finish stays byte-identical.
options.wirePrior.responseIds?	(string | undefined)[]	-

Returns

AsyncGenerator<ChatEvent, TurnMapping>