fix: address pr comments

Author: Unshure

src/strands/experimental/agent_config.py

@@ -8,7 +8,7 @@
 
     agent = config_to_agent("config.json")
     # Add tools that need code-based instantiation
-    agent.process_tools([ToolWithConfigArg(HttpsConnection("localhost"))])
+    agent.tool_registry.process_tools([ToolWithConfigArg(HttpsConnection("localhost"))])
 """
 
 import json

test.json

@@ -0,0 +1,3 @@
+{
+    "prompt": "Hello!"
+}

test.py

@@ -0,0 +1,6 @@
+from strands.experimental.agent_config import config_to_agent
+
+agent = config_to_agent("test.json")
+
+print(agent.system_prompt)
+agent.tool_registry.process_tools()

tests_integ/fixtures/say_tool.py

@@ -0,0 +1,7 @@
+from strands import tool
+
+
+@tool
+def say(input: str) -> str:
+    """Say the input"""
+    return f"Said: {input}"

tests_integ/fixtures/test_agent.json

@@ -0,0 +1,6 @@
+{
+    "model": "global.anthropic.claude-sonnet-4-5-20250929-v1:0",
+    "tools": ["tests_integ.fixtures.say_tool:say"],
+    "prompt": "You use the say tool to communicate",
+    "name": "Sayer"
+}

tests_integ/test_agent_json.py

@@ -0,0 +1,13 @@
+from strands.experimental import config_to_agent
+
+
+def test_load_agent_from_config():
+    agent = config_to_agent("file://tests_integ/fixtures/test_agent.json")
+
+    result = agent("Say hello")
+
+    assert "Sayer" == agent.name
+    assert "You use the say tool to communicate" == agent.system_prompt
+    assert agent.tool_names[0] == "say"
+    assert agent.model.get_config().get("model_id") == "global.anthropic.claude-sonnet-4-5-20250929-v1:0"
+    assert "hello" in str(result).lower()