fix: require current a2a init scaffold

agent_builder/tools.py

@@ -128,7 +128,7 @@ def build_tools(ctx: ToolContext) -> list[Any]:
         try:
             files = _render_a2a_init_template(name, description=description)
             prefix = _agent_prefix(name)
-        except (OSError, ValueError) as exc:
+        except (OSError, RuntimeError, ValueError) as exc:
             return json.dumps({"error": str(exc)})
         written: list[dict[str, Any]] = []
         for path, content in files.items():
@@ -519,7 +519,7 @@ def _render_a2a_init_template(
 ) -> dict[str, str]:
     _validate_name(name)
     class_name = _class_name(name)
-    return {
+    files = {
         "agent.py": _render_sdk_template(
             "agent.py.tmpl",
             name=name,
@@ -533,6 +533,44 @@ def _render_a2a_init_template(
         ),
         "requirements.txt": _render_sdk_template("requirements.txt.tmpl"),
     }
+    _assert_current_a2a_init_template(files)
+    return files
+
+
+def _assert_current_a2a_init_template(files: dict[str, str]) -> None:
+    required_markers = {
+        "agent.py": (
+            "LLMProvisioning.CALLER_PROVIDED",
+            "ctx.llm",
+            "create_deep_agent",
+            "wrap_model_call",
+            "ChatOpenAI",
+        ),
+        "requirements.txt": (
+            "deepagents>=0.5.0",
+            "langchain-openai",
+        ),
+    }
+    missing: list[str] = []
+    for path, markers in required_markers.items():
+        content = files.get(path, "")
+        for marker in markers:
+            if marker not in content:
+                missing.append(f"{path}:{marker}")
+    if not missing:
+        return
+
+    try:
+        import a2a_pack
+
+        version = getattr(a2a_pack, "__version__", "unknown")
+    except Exception:  # noqa: BLE001
+        version = "unknown"
+    raise RuntimeError(
+        "installed a2a-pack init template is stale; expected the 0.1.3+ "
+        "DeepAgents caller-LLM scaffold. "
+        f"a2a_pack={version}; missing markers: {', '.join(missing)}"
+    )
 
 
 def _render_sdk_template(template: str, /, **vars: str) -> str: