diff --git a/packages/opencode/src/tool/apply_patch.ts b/packages/opencode/src/tool/apply_patch.ts
index 84e84cc3962e..f57b9328ab8f 100644
--- a/packages/opencode/src/tool/apply_patch.ts
+++ b/packages/opencode/src/tool/apply_patch.ts
@@ -169,7 +169,13 @@ export const ApplyPatchTool = Tool.define(
               ),
             )
             const contentToDelete = source.text
-            const deleteDiff = trimDiff(createTwoFilesPatch(filePath, filePath, contentToDelete, ""))
+            // Skip diff for large/binary files to prevent storing hundreds of MB in SQLite.
+            // V8 string limit is ~512MB; a 142MB binary file produces a 380MB+ diff.
+            const DIFF_SIZE_LIMIT = 512 * 1024 // 512 KB
+            const deleteDiff =
+              contentToDelete.length > DIFF_SIZE_LIMIT
+                ? ""
+                : trimDiff(createTwoFilesPatch(filePath, filePath, contentToDelete, ""))
 
             const deletions = contentToDelete.split("\n").length
 
diff --git a/packages/opencode/src/tool/edit.ts b/packages/opencode/src/tool/edit.ts
index ea3aac34807d..7d676f65b15c 100644
--- a/packages/opencode/src/tool/edit.ts
+++ b/packages/opencode/src/tool/edit.ts
@@ -635,7 +635,10 @@ export const ContextAwareReplacer: Replacer = function* (content, find) {
   }
 }
 
+const DIFF_MAX_BYTES = 512 * 1024 // 512 KB — keeps SQLite rows manageable and well under V8's string limit
+
 export function trimDiff(diff: string): string {
+  if (diff.length > DIFF_MAX_BYTES) return ""
   const lines = diff.split("\n")
   const contentLines = lines.filter(
     (line) =>