Model aliases and deprecations: build an endpoint inventory

Maintain an inventory linking each application route to its requested alias, resolved model, provider endpoint and owner. Pinning a model reduces unplanned movement, but does not keep a retired API available forever.

Official deprecation notices reviewed in October 2026 include recent shutdown dates, making this an operational inventory problem rather than a future-only migration concern. The narrow task here is finding exposure before a deadline; the model-quality migration itself is a separate project.

What the documentation establishes

OpenAI deprecations publishes dated notices, shutdown schedules and suggested replacements. A suggested replacement is a starting point for testing, not proof of equivalent behavior. OpenRouter provider routing documents provider-routing controls, reinforcing that an application’s model name may not fully identify the serving path.

Decision worksheet

How to test your implementation

1. Search configuration, source code, gateway routes and scheduled jobs for model IDs. Include test automation and disaster-recovery routes.
2. Compare configured models with observed request logs using safe metadata only. An unused configuration and an active endpoint need different urgency.
3. Assign every deprecation notice to an owner and affected workload. Record the provider’s stated date rather than inventing a local grace period.
4. Run a staging test that makes the retiring endpoint unavailable. Confirm the error is actionable and the replacement route is policy-approved.
5. After migration, query traffic for the old ID over a representative business cycle. A successful new deployment does not prove all old callers stopped.

Worked example

Hypothetical inventory: the web app uses a pinned model, but a nightly document job and a fallback route still use an alias scheduled for retirement. Updating the main client leaves two exposures. The release checklist closes only when all three routes have owners, tested replacements and observed traffic evidence. Retain a record of any unknown resolved model so an alias cannot appear more precise than it is.

When to proceed—and when to stop

Use stable IDs where available and monitor the provider’s notices, but plan for replacement testing. Keep fallback lists free of already retired models. Do not solve an inventory warning by deleting the route record while traffic still uses it. When a provider cannot disclose a resolved version, record that limit and increase behavioral monitoring rather than asserting reproducibility.

Evidence scope and maintenance

Source review: October 6, 2026. This is a documentation-led engineering guide, not a hands-on certification of every gateway. Provider examples establish only the behavior described in the cited API documentation. Worksheets and test procedures are GatewayScore editorial recommendations; numerical examples are hypothetical unless explicitly attributed. Review on provider notices, adapter upgrades and newly introduced aliases. Keep inventory ownership current.

Related GatewayScore guidance

Continue with Model migration acceptance, Vendor continuity. Use the model directory to inspect provider-listed options, then verify the exact endpoint and account terms.

Sources reviewed

• OpenAI deprecations — reviewed October 6, 2026.
• OpenRouter provider routing — reviewed October 6, 2026.