@nhtio/adk

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@nhtio/adk/batteries/context ​

Aggregate barrel for bundled context-management batteries — strategies for fitting a large working set of messages, memories, retrievables, thoughts, and tools into a model's context window.

Remarks ​

A context-management battery answers one question: given more candidate content than a dispatch's window can hold, what do you send? Different strategies answer this differently, at different costs:

  • thrift (available now, re-exported below): SUBTRACTIVE — start with everything reasonable, then shed the lowest-signal content first (an image, stale tool results, the RAG tail, low-value memories, old turns, guidance thoughts, then tools as a last resort) until the dispatch fits. Every decision is a measured token comparison; zero extra model calls. See @nhtio/adk/batteries/context/thrift for the full algorithm and its head-to-head evaluation results.
  • compact (available now, re-exported below): SUMMARIZING — instead of shedding old turns outright, pay for a model call to compress them into a running summary message, trading a real API cost for retaining compressed signal from everything folded away. thrift already carries the one hook compact needs to coexist with it (the isSummaryMessage predicate on @nhtio/adk/batteries/context/thrift/subtractive_pass!SubtractToFitOptions), so a caller can run compact upstream and thrift downstream in the same pipeline without the two strategies fighting over the same running-summary message. See @nhtio/adk/batteries/context/compact for the full algorithm and its head-to-head evaluation results.

These are genuinely different trade-offs, not tiers of the same idea — thrift is the cost-optimal, always-available default; compact is the strategy to reach for when a project can afford (and benefits from, per the honest head-to-head result documented in the thrift battery barrel) paying for compression on top of subtraction. Both are meant to be composable, not mutually exclusive.

References ​

argText ​

Re-exports argText

assembleCompactedTurns ​

Re-exports assembleCompactedTurns

AssembleCompactedTurnsOptions ​

Re-exports AssembleCompactedTurnsOptions

AssembleCompactedTurnsResult ​

Re-exports AssembleCompactedTurnsResult

BucketTrace ​

Re-exports BucketTrace

COMPACTION_SYSTEM_PROMPT ​

Re-exports COMPACTION_SYSTEM_PROMPT

CompactionCostEvent ​

Re-exports CompactionCostEvent

ContentLike ​

Re-exports ContentLike

contentTokens ​

Re-exports contentTokens

DEFAULT_ENCODING ​

Re-exports DEFAULT_ENCODING

DEFAULT_KEEP_VERBATIM ​

Re-exports DEFAULT_KEEP_VERBATIM

DEFAULT_RESERVE_FRACTION ​

Re-exports DEFAULT_RESERVE_FRACTION

DEFAULT_SUMMARISE_AT_TOKENS ​

Re-exports DEFAULT_SUMMARISE_AT_TOKENS

DEFAULT_SUMMARY_MESSAGE_ID ​

Re-exports DEFAULT_SUMMARY_MESSAGE_ID

DEFAULT_THIS_TURN_RESULT_KEEP ​

Re-exports DEFAULT_THIS_TURN_RESULT_KEEP

E_CONTEXT_RESOLVER_MISSING ​

Re-exports E_CONTEXT_RESOLVER_MISSING

Estimable ​

Re-exports Estimable

EstimateTokensFn ​

Re-exports EstimateTokensFn

EstimatorOptions ​

Re-exports EstimatorOptions

groupHistoryIntoTurns ​

Re-exports groupHistoryIntoTurns

HistoryTurn ​

Re-exports HistoryTurn

IsEphemeralMessageFn ​

Re-exports IsEphemeralMessageFn

IsSummaryMessageFn ​

Re-exports IsSummaryMessageFn

MillisTimestamp ​

Re-exports MillisTimestamp

OnCostFn ​

Re-exports OnCostFn

RELEVANCE_FLOOR_CURVE ​

Re-exports RELEVANCE_FLOOR_CURVE

RELEVANCE_FLOOR_MAX ​

Re-exports RELEVANCE_FLOOR_MAX

RELEVANCE_FLOOR_MIN ​

Re-exports RELEVANCE_FLOOR_MIN

RelevanceMessage ​

Re-exports RelevanceMessage

RelevanceToolCall ​

Re-exports RelevanceToolCall

relevanceToQuery ​

Re-exports relevanceToQuery

RenderToolsFn ​

Re-exports RenderToolsFn

resolveBudget ​

Re-exports resolveBudget

scaledRelevanceFloor ​

Re-exports scaledRelevanceFloor

selectNaiveTurns ​

Re-exports selectNaiveTurns

SelectNaiveTurnsOptions ​

Re-exports SelectNaiveTurnsOptions

selectRelevantTurns ​

Re-exports selectRelevantTurns

SelectRelevantTurnsOptions ​

Re-exports SelectRelevantTurnsOptions

ShedRankFn ​

Re-exports ShedRankFn

stripPriorTurnThoughts ​

Re-exports stripPriorTurnThoughts

subtractToFit ​

Re-exports subtractToFit

SubtractToFitOptions ​

Re-exports SubtractToFitOptions

summariseTurns ​

Re-exports summariseTurns

SummariseTurnsOptions ​

Re-exports SummariseTurnsOptions

SummarizeFn ​

Re-exports SummarizeFn

ThriftTrace ​

Re-exports ThriftTrace

WorkingImage ​

Re-exports WorkingImage

WorkingMemory ​

Re-exports WorkingMemory

WorkingMessage ​

Re-exports WorkingMessage

WorkingRetrievable ​

Re-exports WorkingRetrievable

WorkingSet ​

Re-exports WorkingSet

WorkingThought ​

Re-exports WorkingThought

WorkingTool ​

Re-exports WorkingTool

WorkingToolCall ​

Re-exports WorkingToolCall

WorkingToolRegistry ​

Re-exports WorkingToolRegistry

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