Model retirements · Gemini API · checked

deep-research-pro-preview-12-2025 (Gemini API) shutdown from 23 October 2026

Google shuts down deep-research-pro-preview-12-2025 on the Gemini API no earlier than 23 October 2026 (the earliest date Google gives) and recommends deep-research-preview-04-2026 as the replacement. No price ratio: prices were not compared for this preview agent on 19 October 2026, so no ratio is given. Google's deprecation page documents no API changes for this move. Record your answers before 23 October 2026: after that nobody can ask deep-research-pro-preview-12-2025 again.

Find every place your code and config name it, with this page's facts beside each:

$ npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz scan

npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz scan lists every model ID in your code and config that has a shutdown date, with its replacement, price ratio and this page's link. It needs no account and no API key, reads your files on your machine and sends nothing; its one request fetches this data. Free and MIT licensed.

The facts

Platform
Gemini API
Model ID
deep-research-pro-preview-12-2025
Announced
no date on the page
Shutdown
23 October 2026The earliest possible date; Google says it will confirm the exact date in advance.
Recommended replacement
deep-research-preview-04-2026
List price per million tokens, input / output
Prices were not compared for this preview agent on 19 October 2026, so no ratio is given.

Prices are the provider's list prices for the standard tier, text input and the shortest context tier. A per-token ratio leaves out how many tokens each model spends on the same prompt; only your own prompts show that.

What changes when you move

Google's deprecation page lists no parameter or API changes for this move. The model's answers still change: a replacement is a different model.

How to test the replacement on your own prompts

  1. Find every call that names deep-research-pro-preview-12-2025: npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz scan prints each file and line.
  2. Before 23 October 2026, record what deep-research-pro-preview-12-2025 answers on a sample of your real prompts, with the token counts Google reports, on your own key: npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz capture prompts.jsonl --model deep-research-pro-preview-12-2025. After the shutdown that record cannot be made.
  3. Run the same prompts on deep-research-preview-04-2026, a cheaper sibling and a model from another provider, and compare with checks that need no judge: exact or normalised match, JSON validity and schema, tool-call names and arguments, refusals and length. npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz compare does this on your keys.
  4. Price the move with the token counts each provider reports for those prompts, not with the list price alone; compare reports the cost per 1,000 calls.

Keep testing until the date

capture and compare run on your keys and keep everything on your machine. To re-run the same prompts against your own endpoint whenever a provider ships a model, with the history kept, npx --allow-remote=root https://agentwares.vercel.app/dl/model-migrate-0.2.0.tgz export --agentcheck writes them as traces that agentcheck imports onto a target you monitor there. On its Pro plan they become checks that re-run when a provider ships a model, with 90 days of history. Re-run them on agentcheck Pro.

Migration watch is not built. It would re-run your captured prompts on each replacement and each new model until 23 October 2026, with no endpoint needed, and email you what changed. If you would pay for that, say so with one click. The click is counted, and nothing else is sent or stored unless you then leave an email.

Also shutting down on 23 October 2026

Other Gemini API retirements

Every announced shutdown, by date

Sources

Built only from the providers' own pages. No vendor intent is implied: a date is what the page says on the day it was read. Data: /models/retirements.json.

model-migrate is a free tool from agentcheck, which re-runs an agent's checks when a provider ships a model and replays recorded traces nightly, so a model change that breaks it arrives as one diff by email.