Tool · 12 cases
Use cases: Codex
Codex is OpenAI's coding agent, used both in the terminal and in the cloud to write code, fix bugs and open pull requests. The cases show developers delegating parallel tasks and reviewing the results afterward. There are also accounts of mistakes and of code that had to be redone. See how each person organized the work, what went well and the prompt used to get started.
12 cases, 5 of them from Brazil, from newest to oldest. The most common topics are productivity, games and creativity, and business and sales. People who show up most: developer, business owner, and accountant. Each case links to the original source, shows a verification date and includes a prompt we wrote.
The cases
12 cases
01Architect connects agents to Grasshopper for parametric geometry
Miro Bannwart's plugin has the agent interview the designer and build connected geometry stations.
02Canceling a subscription and requesting a refund in chat
The agent canceled the subscription, opened a support chat and got the refund.
03Retiree with no coding experience builds a household dinner app
Deirdre Straughan wrote a list of features and let Codex gradually build a local dinner suggestion app.
04Bookkeeping for a Swedish company with agents
A cofounder had agents read receipts, suggest accounts and VAT, and prepare entries for approval.
05Recipes picky kids will eat, organized by Codex
Beth Gebhard asked for recipes from a favorite site; the agent filtered them, rated them and created a spreadsheet and a Drive folder.
06Two agents reviewing each other on the company tax return
Claude Code wrote the calculations from QuickBooks data and Codex reviewed them until they agreed.
07Estimating how long your AI plan will last before it runs out
A dev published an open calculation to estimate how many tokens fit into the Pro/Max plans.
08Building a personal routine app for ADHD with Codex
An auditor created Neurodiário to organize tasks and record information useful for appointments.
09Teaching an agent to use your bank's API
A developer created an open source skill so Codex and Claude Code can integrate with the Banco Inter API.
10Sending AI summaries and research straight to your Kindle
A developer built a Go MCP in minutes that lets Claude or Codex send texts to a Kindle.
11Setting up a monthly bank reconciliation routine with AI
A finance professional describes how to use ChatGPT to cross-check a bank statement against the general ledger and flag differences.
12Redoing an Event Schedule Straight from Your Phone
Simon Willison scraped a conference website and built a better interface using only his phone.