Most migrations are configuration changes: set the delivered base URL and API key, then use the exact model ID from the setup email and verify it with /v1/models before a long run.
Operator-reviewed
Maintained by the unlimitedcodex operator team responsible for manual API setup delivery, base URL handoff, package dates, and customer support workflows.
What transfers unchanged
Chat completion payloads, embeddings requests, image request shapes, Bearer authentication, and most SDK configuration patterns stay the same.
If you already use environment variables for secrets, keep that pattern. Store the delivered unlimitedcodex key server-side and point clients at the delivered /v1 base URL.
Migration checklist
Choose GPT-5.5 XHigh Weekly for a short sprint or Monthly for ongoing builds, or choose GPT-5.6 Sol Weekly or Monthly when Sol access is required. Complete Stripe checkout and wait for manual setup delivery.
Replace OPENAI_API_KEY with your delivered unlimitedcodex key and update the base URL in your OpenAI-compatible client.
Use the exact model ID from your setup email and verify it with /v1/models, then run a low-volume smoke test before production traffic.
When OpenAI API is still the better fit
Stay on first-party OpenAI when you need official enterprise contracts, same-day first-party feature access, or procurement through OpenAI directly.
Choose unlimitedcodex when predictable package pricing matters for GPT-5.5 XHigh at $19/week or an eligible $59 first month followed by $69/month or GPT-5.6 Sol at an eligible $69 first week followed by $89/week, or a $179 first month followed by $199/month, and manual delivery plus 4 concurrent connections fit the workload.