Function stripToolReferenceBlocksFromUserMessage

src/utils/messages.ts:1677–1730

(
  message: UserMessage,
)

 * When tool search is disabled, we need to remove these blocks to avoid API errors.
 */
export function stripToolReferenceBlocksFromUserMessage(
  message: UserMessage,
): UserMessage {
  const content = message.message.content
  if (!Array.isArray(content)) {
    return message
  }

  const hasToolReference = content.some(
    block =>
      block.type === 'tool_result' &&
      Array.isArray(block.content) &&
      block.content.some(isToolReferenceBlock),
  )

  if (!hasToolReference) {
    return message
  }

  return {
    ...message,
    message: {
      ...message.message,
      content: content.map(block => {
        if (block.type !== 'tool_result' || !Array.isArray(block.content)) {
          return block
        }

        // Filter out tool_reference blocks from tool_result content
        const filteredContent = block.content.filter(
          c => !isToolReferenceBlock(c),
        )

        // If all content was tool_reference blocks, replace with a placeholder
        if (filteredContent.length === 0) {
          return {
            ...block,
            content: [
              {
                type: 'text' as const,
                text: '[Tool references removed - tool search not enabled]',
              },
            ],
          }
        }

        return {
          ...block,
          content: filteredContent,
        }
      }),
    },
  }
}

/**
 * Strips the 'caller' field from tool_use blocks in an assistant message.