HiAPI invalid_request: Fix a Wrong Model Endpoint

TL;DR

invalid_request indicates a request problem. A wrong endpoint is one possible cause; the response message, request body, and model ID determine the next check. Confirm the supported endpoint before changing fields.

Before running the Python examples, install the dependency in the same environment: python -m pip install requests.

Choose the request endpoint

These are three common HiAPI generation endpoints. A model page and the public catalog identify which ones a particular model supports.

Endpoint	Main body fields	Purpose
/v1/tasks	model + input	Image, video, and audio tasks
/v1/chat/completions	model + messages	Models supporting chat requests
/v1/responses	model + input	Models supporting Responses

In supported_endpoint_types, task, openai, and openai-response map to these endpoints respectively. The catalog can include other protocol types; use that model's integration documentation for types outside this table.

Read the supported endpoints

Set HIAPI_MODEL to the exact ID shown on the model page. This script reads the public catalog without submitting a generation task.

import os
import requests

model_id = os.environ["HIAPI_MODEL"]
response = requests.get("https://api.hiapi.ai/api/pricing", timeout=30)
response.raise_for_status()
models = response.json()["data"]
model = next((m for m in models if m.get("model_name") == model_id), None)
if model is None:
    raise SystemExit("Model not present in the public catalog; check its exact model ID")
print("model:", model["model_name"])
print("supported_endpoint_types:", model.get("supported_endpoint_types", []))

Four steps to repair the request

1. Check the actual hostname and path, including accidental duplication of /v1 in the base URL.
2. Match the exact model ID and supported endpoint. A display name is not a substitute for an API model ID.
3. Update the body as well as the path: chat messages cannot be copied unchanged into a task request; task parameters belong inside input.
4. Read the HTTP status and error fields again. If it still fails, keep the request ID, model ID, path, and a credential-free request body.

Separate routing, parameters, and authentication

Symptom	Next check
400 with an invalid-request message	Endpoint, JSON, required fields, and types
Explicit unsupported-protocol message	An endpoint declared by the model
401 for a missing or invalid credential	Bearer header and runtime environment variable
MODEL_UNAVAILABLE from the task endpoint	Model ID, availability, and account access

Task rejection responses can use top-level error_code; other endpoints may use error.code. Do not assume a single error field covers every endpoint.

FAQ

Does invalid_request always mean the wrong endpoint?

No. Invalid fields, JSON, or missing required values can also cause rejection. Read the message before changing the endpoint.

Is changing the URL enough?

The request body must match too. Chat messages and the task input object have different structures.

What if the model is absent from the public catalog?

Check the exact ID, model page, and account-visible models. Do not silently substitute a similarly named model.

Does this diagnostic code generate content?

No. It only reads the public catalog. A separate generation submission starts a task.

Next checks

• HiAPI key troubleshooting
• OpenAI key troubleshooting
• HiAPI task documentation