Function convertMCPContentBlock

packages/agent-core/src/mcp/output.ts:71–140

(block: MCPContentBlock)

 * resource shapes) so the caller can drop them.
 */
export function convertMCPContentBlock(block: MCPContentBlock): ContentPart | null {
  if (block.type === 'text' && typeof block.text === 'string') {
    return { type: 'text', text: block.text };
  }

  if (block.type === 'image' && typeof block.data === 'string') {
    const mimeType = block.mimeType ?? 'image/png';
    return {
      type: 'image_url',
      imageUrl: { url: `data:${mimeType};base64,${block.data}` },
    };
  }

  if (block.type === 'audio' && typeof block.data === 'string') {
    const mimeType = block.mimeType ?? 'audio/mpeg';
    return {
      type: 'audio_url',
      audioUrl: { url: `data:${mimeType};base64,${block.data}` },
    };
  }

  // EmbeddedResource: payload is nested under `resource`, as
  // TextResourceContents (`text`) or BlobResourceContents (`blob`).
  if (block.type === 'resource' && typeof block.resource === 'object' && block.resource !== null) {
    const res = block.resource;
    if (typeof res.text === 'string') {
      return { type: 'text', text: res.text };
    }
    if (typeof res.blob === 'string') {
      const mimeType = res.mimeType ?? 'application/octet-stream';
      if (mimeType.startsWith('image/')) {
        return {
          type: 'image_url',
          imageUrl: { url: `data:${mimeType};base64,${res.blob}` },
        };
      }
      if (mimeType.startsWith('audio/')) {
        return {
          type: 'audio_url',
          audioUrl: { url: `data:${mimeType};base64,${res.blob}` },
        };
      }
      if (mimeType.startsWith('video/')) {
        return {
          type: 'video_url',
          videoUrl: { url: `data:${mimeType};base64,${res.blob}` },
        };
      }
      return null;
    }
    return null;
  }

  // ResourceLink: URL reference, not an inline blob.
  if (block.type === 'resource_link' && typeof block.uri === 'string') {
    const mimeType = block.mimeType ?? 'application/octet-stream';
    if (mimeType.startsWith('image/')) {
      return { type: 'image_url', imageUrl: { url: block.uri } };