diff --git a/surfsense_backend/app/capabilities/web/scrape/schemas.py b/surfsense_backend/app/capabilities/web/scrape/schemas.py
index 3e77dd56b..91de17a53 100644
--- a/surfsense_backend/app/capabilities/web/scrape/schemas.py
+++ b/surfsense_backend/app/capabilities/web/scrape/schemas.py
@@ -4,13 +4,21 @@ from __future__ import annotations
 
 from typing import Literal
 
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
+
+MAX_SCRAPE_URLS = 20
+"""Per-call batch cap: bounds a synchronous request's crawl fan-out (05)."""
 
 
 class ScrapeInput(BaseModel):
-    urls: list[str]
+    urls: list[str] = Field(min_length=1, max_length=MAX_SCRAPE_URLS)
     max_length: int = 50_000
 
+    @property
+    def estimated_units(self) -> int:
+        """Worst-case billable crawls for pre-flight: one per requested URL."""
+        return len(self.urls)
+
 
 class ScrapeRow(BaseModel):
     url: str