Celonis builds a human-in-the-loop expense-audit agent with Make AI Agents and Vertex AI
Celonis faced a five-figure annual cost for third-party auditing tools and limited Travel & Expense team capacity. It built a human-in-the-loop expense report auditing agent with Make AI Agents: the agent runs policy checks on amounts, dates, age and category rules, then sends receipts and policies to Vertex AI (Gemini) for deeper analysis. The extra spend was $150 for Vertex AI, cutting annual auditing costs by 99.7% while improving accuracy.
- Agent or tool
- Make AI Agents with Vertex AI
- Topic
- Finance
- Reported on
- Case study (Make)
- Added
- 2026-11-13
Why it matters
Money tasks are tedious but high-stakes, which is exactly where a careful agent helps: it does the checking and paperwork while a person keeps the final say. It is one of 156 sightings filed under Finance on Agent Sightings (number 32 by interest), and one of 1 involving Make AI Agents with Vertex AI.
How you could try it
Here is a reusable prompt, written by us in our own words, that captures the task. Paste it into Make AI Agents with Vertex AI or any similar agent and adjust the details to your situation.
I want an agent to check these finance items against policy and escalate the doubtful ones to a person. The tool in the source case was Make AI Agents with Vertex AI.
Tip: Keep the agent in 'propose, don't pay' mode: let it gather numbers and draft messages, and approve any payment or account change yourself.
Source
Read the original first-hand account on Case study (Make): https://make.com/success-stories/make-ai-agents-help-celonis-lower-expense-audi…. Our summary is a paraphrase; details are in the source.
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