How One Developer Built a Hallucination-Resistant AI Agent for UK Company Data

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Developer Rohan Singh built Verivello, an AI agent that answers questions about UK companies using official sources such as Companies House, HM Land Registry, the FCA, and sanctions lists. To prevent hallucinations, the system enforces a strict rule: every fact in a response must come directly from a verified tool call, with raw JSON records passed into context unchanged. A second safeguard — entity matching — filters out retrieved records that do not provably correspond to the company a user actually queried, preventing the model from citing accurate data about the wrong entity. Together, these two architectural layers mean the agent returns an honest 'I don't know' rather than a plausible but incorrect answer when no verified record exists. The approach relies on pipeline architecture rather than prompt engineering or fine-tuning, making it applicable to any domain where factual accuracy is critical.

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