Method fetch

crates/opencode-provider/src/responses.rs:2416–2442

(
            &self,
            _request: CustomFetchRequest,
        )

    #[async_trait]
    impl CustomFetchProxy for FakeCustomFetchProxy {
        async fn fetch(
            &self,
            _request: CustomFetchRequest,
        ) -> Result<CustomFetchResponse, ProviderError> {
            Ok(CustomFetchResponse {
                status: 200,
                headers: HashMap::new(),
                body: json!({
                    "id": "resp_1",
                    "model": "gpt-5",
                    "output": [
                        {
                            "type": "message",
                            "content": [
                                {"type": "output_text", "text": "hello from proxy"}
                            ]
                        }
                    ],
                    "usage": {
                        "input_tokens": 1,
                        "output_tokens": 1,
                        "total_tokens": 2
                    }
                })
                .to_string(),
            })
        }

        async fn fetch_stream(
            &self,