fix: web-search-agent local development setup

- Add load_dotenv() to main.py for local .env file support
- Fix AzureAIAgentClient parameter names (project_endpoint, credential)
- Update README with local development instructions

Author: Xue Cai

samples/python/hosted-agents/agent_framework/web-search-agent/README.md

@@ -1,3 +1,49 @@
+# Web Search Agent
+
+A hosted agent that uses Bing Grounding to search the web for current information.
+
+## Local Development
+
+### Prerequisites
+
+- Python 3.10+
+- Azure CLI logged in (`az login`)
+- An Azure AI Foundry project with a Bing Grounding connection
+
+### Setup
+
+1. Create a virtual environment and install dependencies:
+
+```bash
+python -m venv .venv
+source .venv/bin/activate  # On Windows: .venv\Scripts\activate
+pip install -r requirements.txt
+```
+
+2. Create a `.env` file with the following environment variables:
+
+```bash
+AZURE_AI_PROJECT_ENDPOINT=https://<your-foundry-account>.services.ai.azure.com/api/projects/<your-project>
+AZURE_AI_MODEL_DEPLOYMENT_NAME=<your-model-deployment>  # e.g., gpt-4.1-mini
+BING_GROUNDING_CONNECTION_ID=/subscriptions/<subscription-id>/resourceGroups/<resource-group>/providers/Microsoft.CognitiveServices/accounts/<foundry-account>/projects/<project>/connections/<bing-connection-name>
+```
+
+### Run the agent locally
+
+```bash
+python main.py
+```
+
+The server will start on `http://localhost:8088`.
+
+### Test the agent
+
+```bash
+curl -X POST http://localhost:8088/responses \
+  -H "Content-Type: application/json" \
+  -d '{"input": "What is the latest news in AI?"}' | jq .
+```
+
 ## Troubleshooting
 
 ### Images built on Apple Silicon or other ARM64 machines do not work on our service

samples/python/hosted-agents/agent_framework/web-search-agent/main.py

@@ -17,8 +17,8 @@ def create_agent() -> ChatAgent:
     )
 
     chat_client = AzureAIAgentClient(
-        endpoint=os.environ["AZURE_AI_PROJECT_ENDPOINT"],
-        async_credential=DefaultAzureCredential(),
+        project_endpoint=os.environ["AZURE_AI_PROJECT_ENDPOINT"],
+        credential=DefaultAzureCredential(),
     )
 
     bing_search_tool = HostedWebSearchTool(