From 948c69e2e547236db1841f6f8471586ce6a71a36 Mon Sep 17 00:00:00 2001
From: Cursor Agent <cursoragent@cursor.com>
Date: Sun, 2 Aug 2026 23:53:39 +0000
Subject: [PATCH] fix(cli): handle empty YAML prompts

---
 src/prompts/processors/yaml.ts       | 5 +++--
 test/prompts/processors/yaml.test.ts | 5 ++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/prompts/processors/yaml.ts b/src/prompts/processors/yaml.ts
index ba1470b1df3d..cf135b8f6880 100644
--- a/src/prompts/processors/yaml.ts
+++ b/src/prompts/processors/yaml.ts
@@ -27,8 +27,9 @@ export function processYamlFile(filePath: string, prompt: Partial<Prompt>): Prom
     // Recursively resolve any file:// references in the parsed structure
     const resolved = maybeLoadConfigFromExternalFile(parsed);
 
-    // Convert back to JSON string
-    maybeParsed = JSON.stringify(resolved);
+    // Convert back to JSON while preserving the raw contents of empty YAML documents.
+    // JSON.stringify(undefined) returns undefined, but Prompt.raw must always be a string.
+    maybeParsed = JSON.stringify(resolved) ?? fileContents;
   } catch (e) {
     logger.debug(`Error parsing YAML file ${filePath}: ${e}`);
   }
diff --git a/test/prompts/processors/yaml.test.ts b/test/prompts/processors/yaml.test.ts
index 6f591a649532..0356b5264bb6 100644
--- a/test/prompts/processors/yaml.test.ts
+++ b/test/prompts/processors/yaml.test.ts
@@ -277,9 +277,8 @@ template: "{{ variable }}   "
       const result = processYamlFile(filePath, {});
 
       expect(result).toHaveLength(1);
-      // Empty YAML parses to undefined; maybeLoadConfigFromExternalFile passes it
-      // through; JSON.stringify(undefined) is the literal string "undefined".
-      expect(result[0].raw).toBe(JSON.stringify(undefined));
+      expect(result[0].raw).toBe('');
+      expect(result[0].label).toBe(`${filePath}: `);
     });
   });
 });