压缩请求与真实 callModel 合同

策略的具体实现如下。

export function createContextCompressor(options: {
  id: string;
  instruction: string;
  modelId?: string;
  transport: string;
  maxOutputTokens: number;
  parse(value: unknown): ContextFragment['value'];
}): ContextCompressor {
  const { id, instruction, modelId, transport, maxOutputTokens } = options;
  breakWhile(typeof options.parse !== 'function', 'Context compressor requires a result parser');
  const parse = options.parse.bind(options);
  return Object.freeze({
    id,
    async compress(call: ContextCompressionCall) {
      const result = await call.callModel({
        // Suffix the stage ID so compressor calls are attributable in diagnostics and budgets.
        stageId: `${call.stageId}:compress:${id}`,
        modelId,
        input: [
          { role: 'system', content: instruction },
          {
            role: 'user',
            content: JSON.stringify({
              sourceId: call.fragment.sourceId,
              value: call.fragment.value,
              targetChars: call.targetChars,
            }),
          },
        ],
        maxOutputTokens,
        transport,
      });
      return synchronous(parse(result.value), 'Context result parsers must be synchronous');
    },
  });
}