diff --git a/src/server.ts b/src/server.ts
index 27229e0..e32e7ce 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -54,8 +54,10 @@ for (const tool of allTools) {
     // const jsonSchema = zodToJsonSchema(z.object(tool.inputSchema.properties as z.ZodRawShape));
     // const parsedSchema = z.any().optional().parse(jsonSchema);
 
-    const zodSchema = z.object(tool.inputSchema.properties as z.ZodRawShape); 
-    server.tool(tool.name, zodSchema.shape, wrappedHandler)
+    const rawShape = tool.inputSchema.properties as z.ZodRawShape;
+    // Cast bypasses TS2589: server.tool's generic resolves ShapeOutput<Args>
+    // against the SDK's z3|z4 union schema type, exploding instantiation depth.
+    (server.tool as (name: string, schema: z.ZodRawShape, cb: typeof wrappedHandler) => unknown)(tool.name, rawShape, wrappedHandler);
 
 }
 
diff --git a/src/tools/media.ts b/src/tools/media.ts
index bd5dccf..4501b76 100644
--- a/src/tools/media.ts
+++ b/src/tools/media.ts
@@ -255,7 +255,8 @@ async function loadUploadFromUrl(sourceUrl: string, explicitTitle?: string): Pro
   }
 
   const response = await axios.get<ArrayBuffer>(sourceUrl, { responseType: 'arraybuffer' });
-  const mimeType = normalizeMimeType(response.headers['content-type']);
+  const contentTypeHeader = response.headers['content-type'];
+  const mimeType = normalizeMimeType(typeof contentTypeHeader === 'string' ? contentTypeHeader : undefined);
   const originalFilename = deriveFilenameFromUrl(sourceUrl, mimeType);
   const filename = buildUploadFilename(originalFilename, explicitTitle);