Programming · Tabnews · 🇧🇷 Brazil
Leave a coding agent running for 24 hours and learn from the bill
An experiment letting Claude Code work unsupervised for a full day ended with a high bill and a security scare.
- Profession
- Developer
- Tools
- Claude Code
- Source
- tabnews.com.br ↗
- Country
- 🇧🇷 Brazil
- Report date
- May 11, 2026
- Verified on
- October 24, 2026
What they did
Ran a Claude Code agent for 24 hours with broad permissions to make progress on a project on its own.
How it went
The API bill came to around R$ 2,000, but the author says the worst part was realizing the agent had access to the machine's credentials.
Good to know
Never run agents with "skip permissions" on a machine holding keys, passwords or customer data. Set a spending limit on your API account.
The prompt
Before starting, list everything you will need to access for [task]. Work only inside the folder [path], do not read .env files or keys, and ask for confirmation before any command that installs packages, deletes files or accesses the network.
Replace what is in [brackets]. Prompt written by us from the account, not a literal copy of the source. Do not paste other people’s personal data (privacy laws such as LGPD and GDPR apply).
Summary in our own words. Results as stated in the original account; we have not tested or audited them. Read the source ↗ Found a mistake?
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