Gemini 2.5 access limited, not deprecated: what new projects do

No, Gemini 2.5 is not deprecated. The Gemini API changelog entry for September 18, 2026 says access to the 2.5 models is limited to users who have actively used them, that they continue to be served until further notice, and that new projects should use 3.5 Flash-Lite or 3.8 Flash.

Vendor text is from the changelog, read 2026-10-01. Sume points are from its API reference.

What exactly changed?

The note gives no retirement date. Treat it as an access rule that depends on the project, which is why a model id that works for one team can be refused for a new one.

Who is affected?

Why look ids up instead of hard-coding them?

Access rules like this vary by account, so a hard-coded id can work in one project and fail in another. Sume's GET /v1/catalog returns "Available capabilities, endpoints, runtime readiness, models, and pricing metadata", and an unknown id fails with 404 model_not_found, where the docs say to use /v1/catalog or verify ids. Sume's video docs say its video ids are bare catalog ids; copy the exact id the catalog row shows rather than a vendor's naming.

Sume's public API responses are provider-neutral, so what you read in the catalog is the contract for your key. For the TTS side of Gemini model changes, see the Gemini TTS replacement note.

What should I do this week?

If you call Gemini directly, check which 2.5 ids your projects use and plan a move for new ones to the models named in the note. If you generate media through Sume, fetch the catalog at startup or on a schedule and select ids from it, as the TTS router does with /v1/tts-router/models.