How UK.gov's new AI tool is trained on "synthetic emails"

The UK government's AI and Data Readiness team has developed 'Project Kestrel', an end-to-end prototype that uses OpenAI large language models to generate 'synthetic emails' for training an email-sorting system, overcoming a common data blocker in the public sector. The Government Digital Service created 'Tiger Heron', a synthetic email generator that produces realistic emails without using live data, according to Senior Product Manager Faye Greasley, who said the approach could apply beyond email.

AI /tag/ai/ One of the UK government’s latest AI projects is using OpenAI LLMs to create “synthetic emails” for training an email-sorting system, overcoming a common data blocker for public sector projects. The government’s AI and Data Readiness team shared details of “Project Kestrel” in a gov.uk blog post https://dataingovernment.blog.gov.uk/2026/08/05/how-we-used-ai-to-help-government-manage-its-email-backlog/?ref=thestack.technology recently, describing how the “end-to-end prototype” used LLMs to create a dataset it could train its central Cuckoo system on. Senior Product Manager Faye Greasley said the Government Digital Service team created “Tiger Heron”, a synthetic email generator that produced emails appearing similar to the day-to-day communications processed by the public sector without using live data. She said: “Access to a safe, realistic data set is one of the most common blockers to data innovation in the public sector. Tiger Heron may offer a practical model for getting past it and one that could apply well beyond email.” Tigers, Herons, and Cuckoos Get the full story: Subscribe for free Join peers managing over $100 billion in annual IT spend and subscribe to unlock full access to The Stack’s analysis and events. Subscribe now https://www.thestack.technology/membership/ Already a member? Sign in https://www.thestack.technology/signin/