adding tool to receive photo of listing

lib/mcp/mcpAdapter.js

@@ -220,6 +220,122 @@ export function createMcpServer() {
     },
   );
 
+  // ── get_photo_for_listing ─────────────────────────────────────────────────────
+  server.tool(
+    'get_photo_for_listing',
+    'Fetch and return the photo of a listing by its ID as an image for vision analysis.',
+    {
+      listingId: z.string().describe('The listing ID whose photo to fetch'),
+    },
+    async ({ listingId }, extra) => {
+      const { user, error } = authenticateToolCall(extra, 'get_photo_for_listing');
+      if (error) return normalizeError(error, 'get_photo_for_listing');
+
+      const listing = getListingById(listingId, user.id, user.isAdmin);
+      if (!listing) {
+        return normalizeError('Listing not found or access denied.', 'get_photo_for_listing');
+      }
+
+      const imageUrl = listing.image_url;
+      if (!imageUrl) {
+        return normalizeError('No image available for this listing.', 'get_photo_for_listing');
+      }
+
+      const SUPPORTED_MIME_TYPES = new Set(['image/jpeg', 'image/png', 'image/gif', 'image/webp']);
+
+      let response;
+      try {
+        response = await fetch(imageUrl, {
+          signal: AbortSignal.timeout(10_000),
+          headers: {
+            'User-Agent':
+              'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
+            Accept: 'image/jpeg,image/png,image/webp,image/gif,image/*,*/*',
+          },
+        });
+      } catch (fetchErr) {
+        return normalizeError(`Failed to fetch image: ${fetchErr.message}`, 'get_photo_for_listing');
+      }
+
+      if (!response.ok) {
+        return normalizeError(
+          `Image fetch returned HTTP ${response.status}. Image URL: ${imageUrl}`,
+          'get_photo_for_listing',
+        );
+      }
+
+      const contentType = response.headers.get('content-type') ?? '';
+      const headerMimeType = contentType.split(';')[0].trim().toLowerCase();
+
+      let buffer;
+      try {
+        buffer = await response.arrayBuffer();
+      } catch (readErr) {
+        return normalizeError(`Failed to read image body: ${readErr.message}`, 'get_photo_for_listing');
+      }
+
+      const bytes = new Uint8Array(buffer);
+
+      if (bytes.length < 12) {
+        return normalizeError(
+          `Downloaded file is too small to determine image type. Image URL: ${imageUrl}`,
+          'get_photo_for_listing',
+        );
+      }
+
+      let resolvedMime;
+
+      if (SUPPORTED_MIME_TYPES.has(headerMimeType)) {
+        resolvedMime = headerMimeType;
+      } else {
+        if (bytes[0] === 0xff && bytes[1] === 0xd8 && bytes[2] === 0xff) {
+          resolvedMime = 'image/jpeg';
+        } else if (
+          bytes[0] === 0x89 &&
+          bytes[1] === 0x50 &&
+          bytes[2] === 0x4e &&
+          bytes[3] === 0x47 &&
+          bytes[4] === 0x0d &&
+          bytes[5] === 0x0a &&
+          bytes[6] === 0x1a &&
+          bytes[7] === 0x0a
+        ) {
+          resolvedMime = 'image/png';
+        } else if (bytes[0] === 0x47 && bytes[1] === 0x49 && bytes[2] === 0x46 && bytes[3] === 0x38) {
+          resolvedMime = 'image/gif';
+        } else if (
+          bytes[0] === 0x52 &&
+          bytes[1] === 0x49 &&
+          bytes[2] === 0x46 &&
+          bytes[3] === 0x46 &&
+          bytes[8] === 0x57 &&
+          bytes[9] === 0x45 &&
+          bytes[10] === 0x42 &&
+          bytes[11] === 0x50
+        ) {
+          resolvedMime = 'image/webp';
+        } else {
+          return normalizeError(
+            `Image format not supported by vision models (header: ${headerMimeType || 'unknown'}). Image URL: ${imageUrl}`,
+            'get_photo_for_listing',
+          );
+        }
+      }
+
+      const base64 = Buffer.from(buffer).toString('base64');
+
+      return {
+        content: [
+          {
+            type: 'image',
+            data: base64,
+            mimeType: resolvedMime,
+          },
+        ],
+      };
+    },
+  );
+
   // ── get_current_date_ime ─────────────────────────────────────────────────────
   server.tool('get_current_date_time', 'Returns the current date and time.', {}, () => {
     return {