From d81144992f522593dc4f225d4054eb1695be1df0 Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Thu, 19 Feb 2026 08:01:43 +0100
Subject: pkg/aflow: fix handling of optional tool arguments

Currently we crash on nil deref, if LLM specifies explicit 'nil'
for an optional (pointer) argument. Handle such cases properly.

Fixes #6811
---
 pkg/aflow/testdata/TestNilToolArg.trajectory.json | 98 +++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 pkg/aflow/testdata/TestNilToolArg.trajectory.json

(limited to 'pkg/aflow/testdata/TestNilToolArg.trajectory.json')

diff --git a/pkg/aflow/testdata/TestNilToolArg.trajectory.json b/pkg/aflow/testdata/TestNilToolArg.trajectory.json
new file mode 100644
index 000000000..518e8a26b
--- /dev/null
+++ b/pkg/aflow/testdata/TestNilToolArg.trajectory.json
@@ -0,0 +1,98 @@
+[
+	{
+		"Seq": 0,
+		"Nesting": 0,
+		"Type": "flow",
+		"Name": "test",
+		"Started": "0001-01-01T00:00:01Z"
+	},
+	{
+		"Seq": 1,
+		"Nesting": 1,
+		"Type": "agent",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:02Z",
+		"Instruction": "Instructions\nPrefer calling several tools at the same time to save round-trips.\n",
+		"Prompt": "Initial Prompt"
+	},
+	{
+		"Seq": 2,
+		"Nesting": 2,
+		"Type": "llm",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:03Z"
+	},
+	{
+		"Seq": 2,
+		"Nesting": 2,
+		"Type": "llm",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:03Z",
+		"Finished": "0001-01-01T00:00:04Z"
+	},
+	{
+		"Seq": 3,
+		"Nesting": 2,
+		"Type": "tool",
+		"Name": "tool",
+		"Started": "0001-01-01T00:00:05Z",
+		"Args": {
+			"Optional": null
+		}
+	},
+	{
+		"Seq": 3,
+		"Nesting": 2,
+		"Type": "tool",
+		"Name": "tool",
+		"Started": "0001-01-01T00:00:05Z",
+		"Finished": "0001-01-01T00:00:06Z",
+		"Error": "missing argument \"Optional\"",
+		"Args": {
+			"Optional": null
+		}
+	},
+	{
+		"Seq": 4,
+		"Nesting": 2,
+		"Type": "llm",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:07Z"
+	},
+	{
+		"Seq": 4,
+		"Nesting": 2,
+		"Type": "llm",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:07Z",
+		"Finished": "0001-01-01T00:00:08Z"
+	},
+	{
+		"Seq": 1,
+		"Nesting": 1,
+		"Type": "agent",
+		"Name": "smarty",
+		"Model": "model",
+		"Started": "0001-01-01T00:00:02Z",
+		"Finished": "0001-01-01T00:00:09Z",
+		"Instruction": "Instructions\nPrefer calling several tools at the same time to save round-trips.\n",
+		"Prompt": "Initial Prompt",
+		"Reply": "Result"
+	},
+	{
+		"Seq": 0,
+		"Nesting": 0,
+		"Type": "flow",
+		"Name": "test",
+		"Started": "0001-01-01T00:00:01Z",
+		"Finished": "0001-01-01T00:00:10Z",
+		"Results": {
+			"Result": "Result"
+		}
+	}
+]
\ No newline at end of file
-- 
cgit mrf-deployment