Real Agent Cases

Make a UK tax research agent from a folder of HMRC manuals with Claude Code

Source date:
Last verified:
Method:
How we verify

Evidence: Screenshots or logsThe source shows screenshots, a transcript or the agent's output.

Outcome

Using scraped HMRC manuals and legislation plus a CLAUDE.md that launches parallel subagents, Claude Code answered an ATT exam question in about 5 minutes, earning roughly 2.5 of 3 marks by the author's grading.

Agent

Claude Code

Prompt Recreated prompt

The source did not publish its exact prompt. This one is our reconstruction from what the source describes.

Not sure how to start? Tell me what you're trying to get done and I'll help you turn it into a clear request.

Goal: Answer this UK tax question using the tax laws and HMRC manuals in this folder.

Quick check first: What's the question, and do you want a short answer or a full working?

What I need from you:
- The question
- A folder with the UK tax legislation and HMRC manuals
- Instructions for how I should work (for example a CLAUDE.md file)

Rules:
- Search the documents in the folder and base the answer on them.
- Split the research across parallel helpers, for example corporate, personal tax, current rates and anti-avoidance.
- If something is missing or unclear, ask me instead of guessing.
- Cite the sections you rely on. This is research, not professional advice.

Output: A structured answer with calculations and references to the sources.

If any of this is unclear, tell me what you have and I'll help fill the gaps.

You'll know it worked when: the answer is backed by specific sections you can check.

Source

https://martinalderson.com/posts/building-a-tax-agent-with-claude-code/

By Martin Alderson · Published Aug 21, 2025 · Added Oct 15, 2026 · Last verified Oct 15, 2026

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