> For the complete documentation index, see [llms.txt](https://docs.nebulaecn.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nebulaecn.com/guides/authentication-guide.md). # Authentication Guide ## Get API key using the interface * Enable Two-factor authentication ![](/files/-MIKlIcjb3D7jRrhhKEy) * Click "Create New" button at My API Keys Section * Enter 2fa code * Please remember the below information after creation: * `Access Key` It is used in API request * `Secret Key` It is used to generate the signature (only visible once after creation) * Click Confirm Button ## **How to use API key** Before calling private endpoint you will need to generate three headers: `X-Auth-Apikey` - API key (from previous step) `X-Auth-Nonce` - A nonce is an arbitrary number that can be used just once. You *MUST* use a millisecond timestamp in UTC time. Read more about it [here](https://en.wikipedia.org/wiki/Cryptographic_nonce). Example: ``` date +%s%3N 1584087661035 ``` `X-Auth-Signature` - HMAC-SHA256 signature calculated using a concatenation of X-Auth-Nonce and X-Auth-Apikey. Hexdigest secret is your API Secret. #### Sample Request below: ``` curl -X GET https://trade.nebulaecn.com/api/v2/backend/account/balances \ -H "X-Auth-Apikey: "Your Api Key" \ -H "X-Auth-Nonce: "Nonce" \ -H "X-Auth-Signature: "HMAC-SHA256 signature" ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.nebulaecn.com/guides/authentication-guide.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.