Error Codes

The API uses standard HTTP status codes to indicate success or failure. All error responses include a JSON body with details.

Error Response Format

JSON

{
  "error": {
    "message": "Invalid API key provided",
    "type": "authentication_error",
    "code": "invalid_api_key"
  }
}

HTTP Status Codes

Code	Status	Description	How to Fix
200	OK	Request succeeded	—
400	Bad Request	Malformed request body or missing required fields	Check request body format and required parameters
401	Unauthorized	Invalid or missing API key	Verify your API key at /settings
402	Insufficient Credits	Account does not have enough credits	Purchase credits at /billing
404	Not Found	Model or resource not found	Check the model slug against available models
429	Rate Limited	Too many requests in the time window	Wait and retry with backoff. See Rate Limits
500	Server Error	Internal server error	Try again later. If persistent, contact support

Error Handling in Code

Using the Railwail SDK, all errors are thrown as RailwailError instances with structured properties.

TypeScript

import railwail, { RailwailError } from "railwail";

const rw = railwail("rw_live_xxxxx");

try {
  await rw.run("gpt-4o", "Hello!");
} catch (err) {
  if (err instanceof RailwailError) {
    console.error(err.status);   // HTTP status code
    console.error(err.type);     // Error category
    console.error(err.code);     // Specific error code
    console.error(err.message);  // Human-readable message
  }
}

See the RailwailError reference for more details on error handling in the SDK.

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