I'm building an Eclipse plugin for code completion using the Hugging Face API. My plugin sends a prompt to the endpoint:

https://router.huggingface.co/hf-inference/v1/chat/completions

I replaced the old endpoint (https://api-inference.huggingface.co) as recommended.
Here’s my Java request code:

String json = "{"
        + "\"inputs\": \"" + safePrompt + "\""
        + "}";

RequestBody body = RequestBody.create(json, MediaType.parse("application/json"));
Request request = new Request.Builder()
        .url("https://router.huggingface.co/hf-inference/v1/chat/completions")
        .addHeader("Authorization", "Bearer " + hfToken)
        .post(body)
        .build();

try (Response response = client.newCall(request).execute()) {
    System.out.println(response.code());
    System.out.println(response.body().string());
}

When I run this, I always get:

Response code: 422
Raw body length: 24
Can someone suggest a free Hugging Face model that works for code completion in Java/Eclipse?