> For the complete documentation index, see [llms.txt](https://docs.nexus.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nexus.xyz/api-reference/authentication/create-api-key.md).

# POST /keys

Create an API key.

`operationId`: `createApiKey`

**Authentication:** `bearerAuth`.

Create a new HMAC API key for the authenticated wallet. Returns the secret once — it is never stored or shown again. Requires a session token (Bearer) from POST /auth/login.

**The host you call this on decides which network the key is valid on.** There is no network parameter in the request and none in the response: the key belongs to the network of the instance that mints it, and any other host refuses it with an opaque `401` that is indistinguishable from an unknown key. Call this on the host you intend to trade against — `api.testnet.nexus.xyz` for play funds, `api.nexus.xyz` for **real funds** — and mint a separate key per network rather than reusing one. See “API keys are bound to one network” in the API description.

## Responses

| Status | Body                     | Meaning                                                                                                                                            |
| ------ | ------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| `200`  | — *(no schema declared)* | Key created                                                                                                                                        |
| `401`  | — *(no schema declared)* | Valid session token required for this host. A session token minted by another network's `POST /auth/login` is refused here like any invalid token. |

## Example

```bash
curl -X POST 'https://exchange.nexus.xyz/api/exchange/keys' \
  -H 'Authorization: Bearer <token>'
```

***

<sub>Generated from</sub> <sub></sub><sub>`eng/apps/exchange/api/openapi.json`</sub> <sub></sub><sub>(spec</sub> <sub></sub><sub>`0.9.27`</sub><sub>). Do not edit by hand — regenerate with</sub> <sub></sub><sub>`python3 product/docs/tools/api-reference/generate.py`</sub><sub>. Hand-authored context lives in the Guides pages.</sub>


---

# 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.nexus.xyz/api-reference/authentication/create-api-key.md?ask=<question>&goal=<endgoal>
```

`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.