> For the complete documentation index, see [llms.txt](https://nexafin.gitbook.io/api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nexafin.gitbook.io/api/mcp/errors.md).

# Error Codes

All errors follow the [JSON-RPC 2.0](https://www.jsonrpc.org/specification#error_object) error format:

```json
{
  "jsonrpc": "2.0",
  "error": {
    "code": -32001,
    "message": "Authentication required"
  },
  "id": 1
}
```

## Standard JSON-RPC errors

| Code     | Name             | Description                                           |
| -------- | ---------------- | ----------------------------------------------------- |
| `-32700` | Parse error      | Invalid JSON in the request body                      |
| `-32600` | Invalid request  | The request is not a valid JSON-RPC request           |
| `-32601` | Method not found | The requested method does not exist                   |
| `-32602` | Invalid params   | Invalid tool arguments or missing required parameters |
| `-32603` | Internal error   | Unexpected server error                               |

## Nexafin MCP errors

| Code     | Name                  | HTTP Status | Description                                         |
| -------- | --------------------- | :---------: | --------------------------------------------------- |
| `-32001` | Authentication error  |     401     | Missing or invalid OAuth token                      |
| `-32002` | Authorization error   |     403     | Token is valid but account is not linked to Nexafin |
| `-32003` | Tool execution error  |     500     | The tool encountered an error during execution      |
| `-32004` | Rate limit exceeded   |     429     | Too many requests — check `Retry-After` header      |
| `-32005` | Subscription required |     403     | An active PRO subscription is required              |

## HTTP status codes

| Status | Meaning                                                                                   |
| ------ | ----------------------------------------------------------------------------------------- |
| `200`  | Success                                                                                   |
| `400`  | Parse error or invalid request                                                            |
| `401`  | Authentication required — includes `WWW-Authenticate` header                              |
| `403`  | Authorization error — account not linked, subscription inactive, or subscription required |
| `404`  | Method not found, or MCP is disabled                                                      |
| `429`  | Rate limit exceeded — check `Retry-After` header                                          |
| `500`  | Internal server error                                                                     |


---

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