Type Alias: SummarizeFn

type SummarizeFn = (req: { system: string; text: string }) => Promise<string>;

Defined in: src/batteries/context/compact/contracts.ts:78

THE model-call seam this battery cannot perform itself: given a system prompt and a body of text to summarize, return the summary text.

Parameters

Parameter	Type	Description
req	{ system: string; text: string; }	system: the compaction instructions (see @nhtio/adk/batteries/context/compact/summarizer!COMPACTION_SYSTEM_PROMPT for the shipped default); text: the body of older conversation (and, on a rolling re-summarize, the prior summary folded in — see @nhtio/adk/batteries/context/compact/summarizer!summariseTurns) to compress.
req.system	string	-
req.text	string	-

Returns

Promise<string>

The summary text, awaited. A rejected promise propagates to the caller of summariseTurns/assembleCompactedTurns uncaught — this battery does not swallow summarizer failures; a caller wanting graceful degradation (e.g. "fall back to the prior summary") implements that inside their own SummarizeFn, exactly as the production flagship agent's own summarizer did.

Remarks

The battery never names DispatchRunner, an adapter, or an executor — it has no idea how the caller talks to a model, and it must not. The canonical ADK recipe for building one (the recipe the production flagship agent this battery was extracted from actually uses, and the one the docs page for this battery walks through in full) is:

const summarize: SummarizeFn = async ({ system, text }) => {
  let out = "";
  const noop = async (): Promise<void> => undefined;
  const noopArr = async (): Promise<never[]> => [];
  await DispatchRunner.dispatch({
    raw: {
      systemPrompt: new Tokenizable(system),
      standingInstructions: [],
      messages: [
        new Message({
          id: `__compact-${Date.now()}`,
          role: "user",
          content: text,
          createdAt: new Date().toISOString(),
          updatedAt: new Date().toISOString(),
        }),
      ],
      // Every other RawTurnContext capability is a noop — this dispatch never reads or writes any
      // OTHER persisted state, it only wants the model's completion text.
      fetchMemories: noopArr,
      fetchRetrievables: noopArr,
      fetchMessages: noopArr,
      fetchThoughts: noopArr,
      fetchToolCalls: noopArr,
      fetchTools: noopArr,
      refreshStandingInstructions: noopArr,
      storeStandingInstruction: noop,
      mutateStandingInstruction: noop,
      deleteStandingInstruction: noop,
      storeMemory: noop,
      mutateMemory: noop,
      deleteMemory: noop,
      storeRetrievable: noop,
      mutateRetrievable: noop,
      deleteRetrievable: noop,
      storeMessage: async (_c, v) => {
        out += v.content?.toString?.() ?? "";
      },
      mutateMessage: noop,
      deleteMessage: noop,
      storeThought: noop,
      mutateThought: noop,
      deleteThought: noop,
      storeToolCall: noop,
      mutateToolCall: noop,
      deleteToolCall: noop,
      storeMediaBytes: noop,
      storeRetrievableBytes: noop,
    } as never,
    executor: await adapter.executor({
      maxTokens: 1200,
      toolCallParser: "none",
      stream: false,
      autoAck: true,
      enableThinking: false,
    }),
  });
  return out.trim();
};

A caller with a different transport (a direct HTTP call to an LLM API, a queue-backed worker, a mocked test double) supplies whatever function satisfies this signature — the battery only ever awaits the returned string.