diff --git a/packages/shared/src/schemas.test.ts b/packages/shared/src/schemas.test.ts
index ca60cb1..f64067c 100644
--- a/packages/shared/src/schemas.test.ts
+++ b/packages/shared/src/schemas.test.ts
@@ -165,10 +165,18 @@ describe('traceRequestSchema', () => {
     });
   });
 
-  it('rejects an invalid url', () => {
-    expect(traceRequestSchema.safeParse({ url: 'not-a-url' }).success).toBe(
-      false,
-    );
+  it('accepts a local game asset path (not just http(s))', () => {
+    // The proxy resolves relative paths against the games root, so a bare
+    // path is a valid trace source.
+    expect(
+      traceRequestSchema.safeParse({ url: 'poker/parts/assets/cards.png' })
+        .success,
+    ).toBe(true);
+  });
+
+  it('rejects a missing or blank url', () => {
+    expect(traceRequestSchema.safeParse({}).success).toBe(false);
+    expect(traceRequestSchema.safeParse({ url: '' }).success).toBe(false);
   });
 
   it('rejects an unknown mode or format', () => {
diff --git a/packages/shared/src/schemas.ts b/packages/shared/src/schemas.ts
index 8796231..477d44d 100644
--- a/packages/shared/src/schemas.ts
+++ b/packages/shared/src/schemas.ts
@@ -59,7 +59,10 @@ export const traceFormatSchema = z.enum(['svg', 'shape']);
 
 /** Query params for `GET /trace`. */
 export const traceRequestSchema = z.object({
-  url: z.string().url('url must be a valid URL'),
+  // The url may be an http(s) URL or a local game asset path relative to the
+  // games root (e.g. `poker/parts/assets/cards.png`); the proxy resolves both
+  // via `resolveAsset`. Only a non-empty string is validated here.
+  url: z.string().min(1, 'url is required'),
   mode: traceModeSchema.default('alpha'),
   threshold: z.coerce.number().int().min(0).max(255).default(128),
   format: traceFormatSchema.default('shape'),