Start with requirements, not a model name
Define task quality, modalities, context, latency, geography, data controls, support and budget. The best choice depends on the workload and operating environment, and may differ across product features.
Run the same evaluation set
Compare providers with representative inputs, clear scoring and the same constraints. Include output quality, refusal behaviour, structured responses, tool use, throughput and total application cost.
Keep the application portable where it matters
Separate provider-specific calls from business logic and retain regression tests. Portability is valuable, but should not prevent the deliberate use of a provider feature that materially improves the product.
References and further reading
Official and independent guidance used to support this practical overview. Product capabilities and pricing can change; verify current provider documentation before making a final decision.