ATS Connector Errors

This guide covers error codes returned by the StackOne API and common ATS provider-specific issues.

HTTP Error Codes

All StackOne API errors follow a consistent response format:

{
  "statusCode": 400,
  "message": "Human-readable error message",
  "timestamp": "2024-01-15T10:30:00.000Z",
  "errorCode": "ValidationError",
  "provider_errors": []
}

Error Code Reference

Code	Name	Description
400	Bad Request	Invalid request parameters or malformed request body
401	Unauthorized	Missing or invalid API key, or expired credentials
403	Forbidden	Valid credentials but insufficient permissions
404	Not Found	Resource does not exist or was deleted
408	Request Timeout	Request took too long to complete
409	Conflict	Request conflicts with current resource state
412	Precondition Failed	Linked account belongs to a disabled integration
422	Unprocessable Entity	Request validation failed
429	Too Many Requests	Rate limit exceeded
500	Internal Server Error	Unexpected server error
501	Not Implemented	Feature not supported for this provider
502	Bad Gateway	Error from upstream provider

ATS Provider-Specific Issues

Teamtailor

Error	Cause	Fix
`501` Bad Request	API key missing permissions	Ask customer to re-authenticate per Teamtailor guide

The hired_at field for candidates indicates when they entered the “Hired” stage in Teamtailor.

Greenhouse

Error	Cause	Fix
`404` Not Found	Invalid Greenhouse user ID provided during account linking	Ask customer to re-authenticate per Greenhouse guide

Lever

Error	Cause	Fix
`400` Invalid Request	Missing or malformed parameter	Check request parameters against documentation
`401` Unauthorized	Invalid credentials or insufficient scopes	Re-verify integration credentials per Lever setup guide
`403` Forbidden	Account settings block operation	Contact Lever Super Admin to update API settings
`429` Too Many Requests	Rate limit exceeded	Use SDK `retryConfig` or implement retry strategy
`500` Server Error	Lever server error	Contact StackOne support
`503` Service Unavailable	Lever maintenance downtime	Retry with exponential backoff

The updated_after filter evaluates any candidate record change, not just specific fields. The updated_at field reflects only selected field updates. Filtering by updated_at values is unsupported.

SmartRecruiters

SmartRecruiters implements restrictive rate limits (1 request per 5 minutes for some endpoints) and doesn’t support listing applications/interviews directly. Default behavior: The interview endpoint filters to candidates in INTERVIEW, OFFERED, HIRED, or TRANSFERRED status only. Candidates with status REJECTED, WITHDRAWN, LEAD, or IN_REVIEW are excluded.

Bullhorn

Bullhorn has relaxed validation that can cause silent failures:

Scenario	Behavior
Invalid `candidate_id` for notes	Note created but remains invisible in UI
Missing `author_id` for notes	Defaults to API user ID

Workable

Candidates created without an associated application are added to a generic talent pool. These candidates will not appear in API responses as the provider doesn’t support returning talent pool candidates.

Debugging Tips

Check Request Logs: View detailed request/response logs in Dashboard → Logs
Inspect provider_errors: The raw provider response is included for 4xx/5xx errors
Use the Playground: Test actions interactively to isolate issues
Verify Permissions: Many 403 errors are due to missing provider-side permissions

Request Logs

View and debug API requests in the dashboard

Getting Started

HRIS

ATS

CRM

LMS

Accounting

ATS Connector Errors

HTTP Error Codes

ATS Provider-Specific Issues

Teamtailor

Greenhouse

Lever

SmartRecruiters

Bullhorn

Workable

Debugging Tips

Request Logs

​HTTP Error Codes

​ATS Provider-Specific Issues

​Teamtailor

​Greenhouse

​Lever

​SmartRecruiters

​Bullhorn

​Workable

​Debugging Tips

Request Logs

HTTP Error Codes

ATS Provider-Specific Issues

Teamtailor

Greenhouse

Lever

SmartRecruiters

Bullhorn

Workable

Debugging Tips