> 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/login.md).

# POST /auth/login

Sign in with EVM wallet.

`operationId`: `login`

**Authentication:** none declared, and the contract declares no document-level default — this operation carries its own signature in the request body. See the description above.

Submit an EIP-191 personal\_sign signature to receive a session token. The session token is used to create and manage API keys via /keys endpoints. For trading, use HMAC API keys instead. Session tokens expire after 24 hours.

## Request body

**Required.** [`LoginRequest`](/api-reference/guides/schemas.md#loginrequest) — `application/json`.

```json
{
  "message": "Sign in to Nexus Exchange",
  "signature": "0x1234...abcd"
}
```

## Responses

| Status | Body                                                              | Meaning                                                                                                                                                                                               |
| ------ | ----------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `200`  | [`LoginResponse`](/api-reference/guides/schemas.md#loginresponse) | Session created                                                                                                                                                                                       |
| `401`  | — *(no schema declared)*                                          | Signature verification failed                                                                                                                                                                         |
| `500`  | — *(no schema declared)*                                          | code=INTERNAL\_ERROR — the session store write failed (M3.15, ENG-10681: the Postgres-backed session store has no in-memory fallback, so a write failure surfaces here instead of degrading silently) |

## Example

```bash
curl -X POST 'https://exchange.nexus.xyz/api/exchange/auth/login' \
  -H 'Content-Type: application/json'
```

***

<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>


---

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