Redbox — the UK Civil Service's Generative-AI Assistant, Built, Scaled and Then Sunset

The Incubator for AI (i.AI), part of the UK Cabinet Office and later the Department for Science, Innovation and Technology, began building Redbox from 2023 as a secure, in-house generative-AI tool to help civil servants summarise policy documents, prepare briefings and search legal and parliamentary material.
Redbox became part of the wider "Humphrey" suite of government AI tools unveiled in 2025 alongside Consult, Parlex, Minute and Lex, and its source code was published openly on GitHub so other teams could inspect or reuse the approach.
Adoption reached over 6,000 users, spanning roughly 150,000 chats and 1.3 million messages, according to i.AI's own figures.
By 2025-2026, with Microsoft Copilot and Google Gemini licensed across government departments, i.AI's test-and-learn evaluation found Copilot delivered comparable functionality more cheaply for users already inside the Microsoft ecosystem. i.AI judged that further investment in Redbox was no longer the best use of resources, kept it running only long enough for the Cabinet Office to migrate onto Gemini, and then formally retired it — publishing a public "lessons learned" retrospective rather than quietly discontinuing the tool. It stands as a documented cautionary case: real adoption did not, on its own, justify continuing a bespoke build once comparable commercial tools became available at scale.

Read the full analysis: https://www.globalgovernmentforum.com/uk-closes-ai-pilots-amid-strategic-changes-to-prioritise-legacy-tech-overhaul/