Function convertCbToModelMessages

common/src/util/messages.ts:213–351

({
  messages,
  includeCacheControl = true,
  logger,
}: {
  messages: Message[]
  includeCacheControl?: boolean
  logger?: Logger
})

}

export function convertCbToModelMessages({
  messages,
  includeCacheControl = true,
  logger,
}: {
  messages: Message[]
  includeCacheControl?: boolean
  logger?: Logger
}): ModelMessage[] {
  const toolMessagesConverted: ModelMessageWithAuxiliaryData[] =
    convertToolMessages(messages)

  const aggregated: ModelMessageWithAuxiliaryData[] = []
  for (const message of toolMessagesConverted) {
    if (aggregated.length === 0) {
      aggregated.push(message)
      continue
    }

    const lastMessage = aggregated[aggregated.length - 1]
    if (
      lastMessage.timeToLive !== message.timeToLive ||
      !isEqual(lastMessage.providerOptions, message.providerOptions) ||
      !isEqual(lastMessage.tags, message.tags)
    ) {
      aggregated.push(message)
      continue
    }
    if (lastMessage.role === 'system' && message.role === 'system') {
      lastMessage.content += '\n\n' + message.content
      continue
    }
    if (lastMessage.role === 'user' && message.role === 'user') {
      lastMessage.content.push(...message.content)
      continue
    }
    if (lastMessage.role === 'assistant' && message.role === 'assistant') {
      lastMessage.content.push(...message.content)
      continue
    }

    aggregated.push(message)
  }

  if (!includeCacheControl) {
    return aggregated
  }

  // Add cache control to specific messages (max of 4 can be marked for caching!):
  // - The message right before the three tagged messages
  // - Last message
  for (const tag of [
    'LAST_ASSISTANT_MESSAGE',
    'USER_PROMPT',
    'STEP_PROMPT',
    undefined, // Last message
  ] as const) {
    let index =