Function formatMessagesForContext

src/utils/telemetry/betaSessionTracing.ts:166–208

* Format user messages for new_context display, separating system reminders. * Only handles user messages (assistant messages are filtered out before this is called).

(messages: UserMessage[])

 * Only handles user messages (assistant messages are filtered out before this is called).
 */
function formatMessagesForContext(messages: UserMessage[]): FormattedMessages {
  const contextParts: string[] = []
  const systemReminders: string[] = []

  for (const message of messages) {
    const content = message.message.content
    if (typeof content === 'string') {
      const reminderContent = extractSystemReminderContent(content)
      if (reminderContent) {
        systemReminders.push(reminderContent)
      } else {
        contextParts.push(`[USER]\n${content}`)
      }
    } else if (Array.isArray(content)) {
      for (const block of content) {
        if (block.type === 'text') {
          const reminderContent = extractSystemReminderContent(block.text)
          if (reminderContent) {
            systemReminders.push(reminderContent)
          } else {
            contextParts.push(`[USER]\n${block.text}`)
          }
        } else if (block.type === 'tool_result') {
          const resultContent =
            typeof block.content === 'string'
              ? block.content
              : jsonStringify(block.content)
          // Tool results can also contain system reminders (e.g., malware warning)
          const reminderContent = extractSystemReminderContent(resultContent)
          if (reminderContent) {
            systemReminders.push(reminderContent)
          } else {
            contextParts.push(
              `[TOOL RESULT: ${block.tool_use_id}]\n${resultContent}`,
            )
          }
        }
      }
    }
  }

  return { contextParts, systemReminders }
}

export interface LLMRequestNewContext {
  /** System prompt (typically only on first request or if changed) */