diff --git a/frontend/src/toolui/VendoredToolUi.tsx b/frontend/src/toolui/VendoredToolUi.tsx
index 0e0179e4..bcf8716a 100644
--- a/frontend/src/toolui/VendoredToolUi.tsx
+++ b/frontend/src/toolui/VendoredToolUi.tsx
@@ -46,8 +46,68 @@ type Gate =
 
 /** Models pad payloads with invented keys; strip ONLY unrecognized-key issues and retry once, so
     sloppiness self-heals while genuinely wrong shapes still fall back loudly. */
+function slugFor(label: unknown, i: number): string {
+  const t = typeof label === 'string' ? label.trim().toLowerCase().replace(/\s+/g, '-').slice(0, 40) : '';
+  return t || `item-${i + 1}`;
+}
+
+// Mechanical repairs for the mistakes agents actually make (numeric ids, ranked priorities, nested
+// row objects, bare action objects). Only ever applied when the strict parse FAILED, and the result
+// is re-validated, so a repair can flip fail->pass but never corrupt a valid payload.
+function repairCommonAgentShapes(props: Record<string, unknown>): Record<string, unknown> {
+  let out: Record<string, unknown>;
+  try {
+    out = JSON.parse(JSON.stringify(props ?? {}, (_k, v) => (v === undefined ? null : v)));
+  } catch {
+    return props;
+  }
+  const fixIdLabel = (arr: unknown): unknown => {
+    if (!Array.isArray(arr)) return arr;
+    return arr.map((o, i) => {
+      if (typeof o === 'string') return { id: slugFor(o, i), label: o };
+      if (o && typeof o === 'object' && !Array.isArray(o)) {
+        const obj = { ...(o as Record<string, unknown>) };
+        if (obj.id == null || obj.id === '') obj.id = slugFor(obj.label, i);
+        else if (typeof obj.id !== 'string') obj.id = String(obj.id);
+        if (typeof obj.label !== 'string' || !obj.label) obj.label = String(obj.label ?? obj.id);
+        return obj;
+      }
+      return o;
+    });
+  };
+  if ('options' in out) out.options = fixIdLabel(out.options);
+  if ('actions' in out) {
+    if (out.actions && !Array.isArray(out.actions) && typeof out.actions === 'object' && 'label' in (out.actions as object)) out.actions = [out.actions];
+    out.actions = fixIdLabel(out.actions);
+  }
+  const PRIORITY_SYNONYMS: Record<string, string> = { '1': 'primary', '2': 'secondary', '3': 'tertiary', high: 'primary', medium: 'secondary', low: 'tertiary', primary: 'primary', secondary: 'secondary', tertiary: 'tertiary' };
+  if (Array.isArray(out.columns)) {
+    out.columns = out.columns.map((c) => {
+      if (c && typeof c === 'object' && 'priority' in (c as object)) {
+        const mapped = PRIORITY_SYNONYMS[String((c as Record<string, unknown>).priority).toLowerCase()];
+        const copy = { ...(c as Record<string, unknown>) };
+        if (mapped) copy.priority = mapped; else delete copy.priority;
+        return copy;
+      }
+      return c;
+    });
+  }
+  if (Array.isArray(out.data)) {
+    out.data = out.data.map((row) => {
+      if (!row || typeof row !== 'object' || Array.isArray(row)) return row;
+      return Object.fromEntries(Object.entries(row as Record<string, unknown>).map(([k, v]) => {
+        if (v !== null && typeof v === 'object' && !Array.isArray(v)) return [k, JSON.stringify(v)];
+        if (Array.isArray(v)) return [k, v.map((x) => (x !== null && typeof x === 'object' ? JSON.stringify(x) : x))];
+        return [k, v];
+      }));
+    });
+  }
+  return out;
+}
+
 function parseLeniently(schema: { safeParse: (v: unknown) => any }, props: Record<string, unknown>): Gate {
   let result = schema.safeParse(props);
+  let base: Record<string, unknown> = props;
   if (!result.success) {
     const issues: Array<{ code: string; keys?: string[]; path: Array<string | number>; message: string }> = result.error.issues;
     if (issues.every((i) => i.code === 'unrecognized_keys')) {
@@ -55,9 +115,14 @@ function parseLeniently(schema: { safeParse: (v: unknown) => any }, props: Recor
       for (const issue of issues) {
         for (const key of issue.keys || []) delete cleaned[key];
       }
+      base = cleaned;
       result = schema.safeParse(cleaned);
     }
   }
+  if (!result.success) {
+    const repaired = schema.safeParse(repairCommonAgentShapes(base));
+    if (repaired.success) return { state: 'ok', parsed: repaired.data as Record<string, unknown> };
+  }
   if (result.success) return { state: 'ok', parsed: result.data as Record<string, unknown> };
   const issues = result.error.issues.slice(0, 2).map((i: { path: Array<string | number>; message: string }) => `${i.path.join('.')}: ${i.message}`).join('; ');
   return { state: 'bad', problem: issues };