upload_media

Instructions

Implementation Reference

• src/tools/files.ts:73-118 (handler)

  The upload_media tool handler: reads a local file, detects content type, gets a signed upload URL from PostFast API, PUTs the file to that URL, and returns the media key, type (VIDEO/IMAGE), and content type.

  server.tool(
    'upload_media',
    'Upload a local file to PostFast and get back a media key for use in create_posts. Handles the full flow: detects content type, gets a signed URL, uploads the file, and returns the key and type.',
    {
      filePath: z
        .string()
        .describe(
          'Absolute path to the local file (e.g. /Users/me/photo.jpg)',
        ),
    },
    async (input) => {
      const contentType = detectContentType(input.filePath);
      const isVideo = contentType.startsWith('video/');
  
      const [uploadUrl] = await client.post<SignedUploadUrl[]>(
        '/file/get-signed-upload-urls',
        { contentType, count: 1 },
      );
  
      const fileBuffer = await readFile(input.filePath);
  
      const uploadResponse = await fetch(uploadUrl.signedUrl, {
        method: 'PUT',
        headers: { 'Content-Type': contentType },
        body: fileBuffer,
      });
  
      if (!uploadResponse.ok) {
        throw new Error(
          `Upload failed (${uploadResponse.status}): ${await uploadResponse.text()}`,
        );
      }
  
      const result = {
        key: uploadUrl.key,
        type: isVideo ? 'VIDEO' : 'IMAGE',
        contentType,
      };
  
      return {
        content: [
          { type: 'text' as const, text: JSON.stringify(result, null, 2) },
        ],
      };
    },
  );

• src/tools/files.ts:76-82 (schema)

  Input schema for upload_media: requires a single string filePath parameter validated with Zod, described as absolute path to a local file.

  {
    filePath: z
      .string()
      .describe(
        'Absolute path to the local file (e.g. /Users/me/photo.jpg)',
      ),
  },

• src/tools/files.ts:73-118 (registration)

  Tool registration via server.tool() in the registerFileTools function, which is called from src/index.ts.

  server.tool(
    'upload_media',
    'Upload a local file to PostFast and get back a media key for use in create_posts. Handles the full flow: detects content type, gets a signed URL, uploads the file, and returns the key and type.',
    {
      filePath: z
        .string()
        .describe(
          'Absolute path to the local file (e.g. /Users/me/photo.jpg)',
        ),
    },
    async (input) => {
      const contentType = detectContentType(input.filePath);
      const isVideo = contentType.startsWith('video/');
  
      const [uploadUrl] = await client.post<SignedUploadUrl[]>(
        '/file/get-signed-upload-urls',
        { contentType, count: 1 },
      );
  
      const fileBuffer = await readFile(input.filePath);
  
      const uploadResponse = await fetch(uploadUrl.signedUrl, {
        method: 'PUT',
        headers: { 'Content-Type': contentType },
        body: fileBuffer,
      });
  
      if (!uploadResponse.ok) {
        throw new Error(
          `Upload failed (${uploadResponse.status}): ${await uploadResponse.text()}`,
        );
      }
  
      const result = {
        key: uploadUrl.key,
        type: isVideo ? 'VIDEO' : 'IMAGE',
        contentType,
      };
  
      return {
        content: [
          { type: 'text' as const, text: JSON.stringify(result, null, 2) },
        ],
      };
    },
  );

• src/tools/files.ts:27-36 (helper)

  Helper function detectContentType maps file extensions to MIME types (jpg/png/gif/webp/mp4/webm/mov). Used by upload_media to determine the Content-Type.

  function detectContentType(filePath: string): string {
    const ext = extname(filePath).toLowerCase();
    const mime = MIME_MAP[ext];
    if (!mime) {
      throw new Error(
        `Unsupported file extension "${ext}". Supported: ${Object.keys(MIME_MAP).join(', ')}`,
      );
    }
    return mime;
  }