fix: show debug info on errors + prompt export function

- Frontend: debug viewer now shows even when test fails
- Frontend: export button to download complete prompt config as JSON
- Backend: attach debug info to JSON validation errors
- Backend: include raw output and length in error details

Users can now debug failed prompts and export configs for analysis.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/prompt_executor.py

@@ -60,28 +60,37 @@ def resolve_placeholders(template: str, variables: Dict[str, Any], debug_info: O
     return result
 
 
-def validate_json_output(output: str, schema: Optional[Dict] = None) -> Dict:
+def validate_json_output(output: str, schema: Optional[Dict] = None, debug_info: Optional[Dict] = None) -> Dict:
     """
     Validate that output is valid JSON.
 
     Args:
         output: String to validate
         schema: Optional JSON schema to validate against (TODO: jsonschema library)
+        debug_info: Optional dict to attach to error for debugging
 
     Returns:
         Parsed JSON dict
 
     Raises:
-        HTTPException: If output is not valid JSON
+        HTTPException: If output is not valid JSON (with debug info attached)
     """
     try:
         parsed = json.loads(output)
         # TODO: Add jsonschema validation if schema provided
         return parsed
     except json.JSONDecodeError as e:
+        error_detail = {
+            "error": f"AI returned invalid JSON: {str(e)}",
+            "raw_output": output[:500] + ('...' if len(output) > 500 else ''),
+            "output_length": len(output)
+        }
+        if debug_info:
+            error_detail["debug"] = debug_info
+
         raise HTTPException(
             status_code=500,
-            detail=f"AI returned invalid JSON: {str(e)}"
+            detail=error_detail
         )
 
 
@@ -169,7 +178,7 @@ async def execute_base_prompt(
     # Validate JSON if required
     output_format = prompt.get('output_format', 'text')
     if output_format == 'json':
-        output = validate_json_output(response, prompt.get('output_schema'))
+        output = validate_json_output(response, prompt.get('output_schema'), debug_info if enable_debug else None)
     else:
         output = response
 
@@ -273,7 +282,7 @@ async def execute_pipeline_prompt(
 
                 # Validate JSON if required
                 if output_format == 'json':
-                    output = validate_json_output(response, prompt_def.get('output_schema'))
+                    output = validate_json_output(response, prompt_def.get('output_schema'), prompt_debug if enable_debug else None)
                 else:
                     output = response
 

frontend/src/components/UnifiedPromptModal.jsx

@@ -236,6 +236,33 @@ export default function UnifiedPromptModal({ prompt, onSave, onClose }) {
     }
   }
 
+  const handleExport = () => {
+    // Export complete prompt configuration as JSON
+    const exportData = {
+      name,
+      slug,
+      display_name: displayName,
+      description,
+      type,
+      category,
+      active,
+      sort_order: sortOrder,
+      output_format: outputFormat,
+      template: type === 'base' ? template : null,
+      stages: type === 'pipeline' ? stages : null
+    }
+
+    const blob = new Blob([JSON.stringify(exportData, null, 2)], { type: 'application/json' })
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    a.download = `prompt-${slug || 'new'}-${new Date().toISOString().split('T')[0]}.json`
+    document.body.appendChild(a)
+    a.click()
+    document.body.removeChild(a)
+    URL.revokeObjectURL(url)
+  }
+
   const handleTest = async () => {
     // Can only test existing prompts (need slug in database)
     if (!prompt?.slug) {
@@ -252,7 +279,30 @@ export default function UnifiedPromptModal({ prompt, onSave, onClose }) {
       setTestResult(result)
       setShowDebug(true)
     } catch (e) {
-      setError('Test-Fehler: ' + e.message)
+      // Show error AND try to extract debug info from error
+      const errorMsg = e.message
+      let debugData = null
+
+      // Try to parse error message for embedded debug info
+      try {
+        const parsed = JSON.parse(errorMsg)
+        if (parsed.detail) {
+          setError('Test-Fehler: ' + parsed.detail)
+          debugData = parsed
+        } else {
+          setError('Test-Fehler: ' + errorMsg)
+        }
+      } catch {
+        setError('Test-Fehler: ' + errorMsg)
+      }
+
+      // Set result with error info so debug viewer shows it
+      setTestResult({
+        error: true,
+        error_message: errorMsg,
+        debug: debugData || { error: errorMsg }
+      })
+      setShowDebug(true) // ALWAYS show debug on test, even on error
     } finally {
       setTesting(false)
     }
@@ -640,7 +690,7 @@ export default function UnifiedPromptModal({ prompt, onSave, onClose }) {
           display: 'flex', gap: 12, justifyContent: 'space-between',
           paddingTop: 16, borderTop: '1px solid var(--border)'
         }}>
-          <div>
+          <div style={{ display: 'flex', gap: 8 }}>
             {prompt?.slug && (
               <button
                 className="btn"
@@ -654,6 +704,14 @@ export default function UnifiedPromptModal({ prompt, onSave, onClose }) {
                 {testing ? '🔬 Teste...' : '🔬 Test ausführen'}
               </button>
             )}
+            <button
+              className="btn"
+              onClick={handleExport}
+              disabled={loading}
+              title="Exportiere Prompt-Konfiguration als JSON"
+            >
+              📥 Export
+            </button>
           </div>
           <div style={{ display: 'flex', gap: 12 }}>
             <button className="btn" onClick={onClose}>