Google's October 8 changelog announced the October 23 retirement of deep-research-pro-preview-12-2025 and named newer research-agent options. The note distinguishes a speed-oriented preview from a maximum-comprehensiveness preview. As of October 26, the announced retirement date has passed.
Treat this as an agent migration
An agent identifier can govern more than the underlying language model. It may affect how research is planned, which sources are consulted, and how results are delivered. Follow the current migration instructions rather than substituting a model name in an unrelated field.
Evaluate the output you rely on
Use questions representative of your business: a market summary, a policy comparison, or a supplier review. Check whether citations resolve, support the claim, and reflect the requested date range.
Include a topic with conflicting evidence and one where the correct answer is that public information is insufficient. A long report is not necessarily a better report.
Choose depth deliberately
A fast result may suit an interactive briefing. A more comprehensive run may suit scheduled analysis. Measure elapsed time, total cost, source coverage, and reviewer effort rather than assuming one option is universally better.
Preserve the research question, agent version, retrieval date, and reviewed output for important decisions. If a migration changes the report format, update downstream consumers and review templates too.
The upgrade succeeds when decision-makers receive reliable evidence in the form they need, not merely when the API request starts succeeding again.
Sources & further reading
Reviewed October 26, 2026. Product availability and regulatory guidance can change. Vendor performance claims are not independent Rovio AI benchmarks.
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