OpenAI Agents SDK errors / Config
agents.exceptions.UserError: Hosted tools are not supported with the ChatCompletions API.
Cause
HostedMCPTool (and tools like WebSearchTool) require the Responses API, but the agent was initialised with OpenAIChatCompletionsModel, which uses the Chat Completions endpoint that does not support hosted tools.
Fix
Switch to the default OpenAIResponsesModel (or omit the model argument) so the SDK uses the Responses API. If you must use Chat Completions, replace hosted tools with MCPServerStdio or MCPServerSse local integrations. Do not mix HostedMCPTool with a ChatCompletions-backed model.
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