Stuck on Agent Scripting API 429 during JMeter load test

Running concurrent load tests against /api/v2/flexible-crm/interactions. The goal is to validate script rendering capacity. After 500 concurrent requests, the API returns 429 Too Many Requests. The JMeter script uses basic auth and standard JSON payloads.

HTTP/1.1 429 Too Many Requests
Retry-After: 2

Is there a specific rate limit for the scripting endpoint that differs from standard interaction APIs? Need to adjust the throttle.