Documentation

Three steps to a full check — no sign-up.

Step 1: Enter the endpoint

On the home page, enter the target platform's endpoint, e.g. https://api.example.com or a /v1 URL.

Step 2: API Key & model

Paste your API Key, pick a target model (GPT-4o, Claude Opus, Gemini, etc.) and a protocol (auto-detect / Anthropic-native / OpenAI-compatible).

Step 3: Start the check

Pass the captcha and click Start. CheckToken sends real requests and shows results item by item: validity, model support, response speed. Your API Key is never stored.

Which protocol?

· Auto-detect: best when unsure; detects the protocol automatically.
· Anthropic native: Claude's native /v1/messages endpoint.
· OpenAI compatible: GPT, DeepSeek, Gemini-compatible endpoints, etc.

Want more? See the FAQ or supported models。

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