AI product · Nov 2025 – present
MestreObra, construction management on WhatsApp
An AI agent on WhatsApp for civil engineers, renovation architects and small builders.
Problem
On a job site a receipt arrives, the crew needs materials and the client wants an update, all at once. Small builders track it in chats and spreadsheets and lose control of costs.
My role
Founder and sole engineer
AI
- The agent understands text, audio, photos and video: a receipt photo becomes an expense on the right job, a voice note becomes the daily log
- Purchase orders organized per job, rain alerts before a concrete pour, a link for the end client to follow the job
- Claude agent with read and write tools, schema validation, server-side authorization and tests per tool
- Prompt caching, model selection by plan and cost tracking per conversation
Result
A single plan with a free trial. The field team never installs anything or creates a password; the manager gets everything organized.
Stack
Anthropic Claude