GPT-5.3-Codex vs GPT-5.6 Luna for workflow automation

**Honest answer:**  
Don’t automate this exact 3-signature chain.  
If you do, you’ll just get a faster version of a bad control design: low-risk claims still queue behind three people, and you’ll still pay £14 fares late.

You’d be **making the wrong thing efficient**.

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The question to answer is:

> **“What is the minimum approval/control model that protects charity funds and trustee duties, while getting legitimate expenses paid quickly?”**

Not: “How do we route every claim through three signatures faster?”

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## What good design loo…

The honest answer is: **do not automate the three-signature process as it stands**. You would make an inefficient control faster, but not necessarily make the charity better controlled.

A £14 claim taking nine days suggests that the problem is not mainly the absence of a workflow tool. It is that the charity is applying the same approval burden to every transaction, regardless of risk. A tool would route the claim neatly through the same unnecessary queue. It might also create false comfort: three electronic approvals can still be three people…