What people do with Codex
OpenAI's coding agent, including the non-coding jobs people give it. 38 real use cases so far, most often for software, work and money. Each links to its source and comes with a prompt to try.
Also called OpenAI Codex, Codex CLI.
38 use cases · 11 kinds of job · Updated Oct 6, 2026
Start here
Hand off coding sessions between agent accounts at usage limits
A developer built an app that tracks usage across multiple Codex and Claude Code accounts and auto-hands-off conversations when one hits its limit.
How it went The source gives no numbers or test results. It lists the app's features (manual account choice, media file management, history search, integrations) and asks for feedback, so how well handoffs preserve context is unreported.
Process and query email across providers via MCP agents
A developer built an email intelligence product using agents and MCP, running on open-source models, that lets LLMs query Gmail and Outlook mailboxes; in private beta.
How it went The codebase is largely done and running in private beta. Public launch is held up waiting on approvals from Google, Microsoft and OpenAI, which the author calls tedious. IMAP and other providers are planned for later.
Fill forms and review tax filings with Codex computer use
Secondhand accounts of OpenAI staff using Codex computer use for forms and PDFs, including one tax filing review that caught an error worth thousands.
How it went The tax review caught an error in the user's favor worth thousands of dollars. The article gives no timings, step-by-step details or failure cases, and only a single tax example.
2 accounts
Build a racing game from a single prompt
Codex made a racing game with multiple racers, eight maps and items from one prompt, acting as designer, developer and QA tester by playing it.
How it went The build produced a racing game with different racers, eight maps and space-bar items, using over 7 million tokens. Earlier iterations are published so you can see how it improved. The source gives no quality assessment.
4 accounts
Summarize months of notes in Logseq via CLI agent
User points Codex at the Logseq CLI docs so it can query and summarize journals and tagged job-application and project pages.
How it went Codex can summarize months of journals, and tagged blocks make queries natural. wosk calls the whole setup very alpha, though, and does not give any numbers.
3 accounts
Jump to a kind of job
Five new use cases in your inbox every morning
The best things people got an AI agent to do, each with the prompt to try it.
Codex for software
Shipping code, reviewing PRs, running infra, and fixing things at 3am.
Hand off coding sessions between agent accounts at usage limits
A developer built an app that tracks usage across multiple Codex and Claude Code accounts and auto-hands-off conversations when one hits its limit.
Resolve a Slack-reported issue with a coding agent
A Codex agent resolved an issue passed to it in about 40 minutes, and an ops agent verified the fix back in Slack.
Build and publish a BaZi chart reading agent
Built solo with coding agents, an agent computes BaZi charts, interprets them, detects language and takes on-chain payments for readings.
Build custom real estate tools for offers and deal tracking
A rental owner used Codex to build tools for formulating offer prices, building property analysis reports with field photos, and tracking transactions under contract.
Catch intent conflicts between parallel coding agents
Agents publish planned changes before editing so conflicting architecture changes across parallel worktrees get flagged before code is written.
Run multi-stage PR reviews with parallel sub-agents
A Claude Code plugin that reviews pull requests in stages with sub-agents and validation passes, with optional ensemble review via Codex.
Turn tickets into merged pull requests
Pulls tasks from GitHub Issues or Linear, then runs Claude Code or Codex in isolated Kubernetes pods to carry each one through to a PR.
Debug overnight with a long-running agent
The author leaves Codex CLI running for hours to add debug prints and test hypotheses against a reproducing unit test, often only to find the bug.
Diagnose a killed process on a server
Codex CLI over SSH found the OOM killer in kernel logs on a 2 GB droplet with no swap and listed fixes by risk without changing anything.
Codex for work
Planning, inboxes, documents, and the back office that runs a business.
Process and query email across providers via MCP agents
A developer built an email intelligence product using agents and MCP, running on open-source models, that lets LLMs query Gmail and Outlook mailboxes; in private beta.
Triage email by voice while walking
Allie Miller used ChatGPT voice mode with Codex to triage important emails, draft replies, archive or delete items and log action items.
Run company departments with persistent self-hosted agents
A self-hosted company OS runs Claude Code and Codex agents per department, with memory, schedules, phone calls via Twilio, and document/video editing.
Run an autonomous employee-like agent for company tasks
Author runs a self-built autonomous agent on Codex, ChatGPT Plus, systemd and email that handles various company tasks, using a rolling context, diary and markdown wiki for memory.
Email scheduled project summaries with Codex
A guide sets up a Codex automation that reads project files on a schedule and emails a weekly summary via the Gmail plugin.
Summarize transcripts and build documents with Codex
A guide shows Codex summarizing transcripts into a Word doc, building an Excel revenue model and making carousel images from a document.
Codex for money
Unclaimed money, refunds, cancelled subscriptions, lower bills, taxes, and insurance.
Fill forms and review tax filings with Codex computer use
Secondhand accounts of OpenAI staff using Codex computer use for forms and PDFs, including one tax filing review that caught an error worth thousands.
2 accounts
Cancel an Amazon subscription and get a refund
Codex navigated Amazon settings to cancel a subscription, then chatted with customer service and secured an immediate $15 refund.
Prepare S-Corp tax filings from bookkeeping data
Claude Code wrote scripts parsing QuickBooks and bank statements, and Codex reviewed the code and caught errors like a wrong Schedule L mapping.
Keep company books with terminal coding agents
The author has kept books for several Swedish companies using Claude Code and Codex, which read receipts, matched bank rows, posted entries and caught a VAT error before filing.
Codex for life admin
Forms, paperwork, health, family logistics, personal assistants, and the smart home.
Run Codex tasks on your Home Assistant config
An integration starts Codex CLI tasks against a Home Assistant config to diagnose failing automations, check dashboards for broken cards and create scripts.
3 accounts
Build a household dinner-suggestion app
A non-coder used Codex to build a local app that suggests dinners from pantry stock, garden produce, diets, appliances and weather.
Handle family errands and recipe sorting with Codex
A communications professional had Codex email her son's doctor for a refill and sort 240 recipes down to 62 family-fit ones into an index, spreadsheet and Drive folder.
Codex for sales & marketing
Finding leads, running outreach, answering customers, and growing revenue.
Run a solo business with a team of 16 agents
A solo founder uses ~16 Claude and Codex agents for lead research, cold emails, CRM upkeep, SEO content and call prep, and says it found and qualified a first pilot customer.
Rank CRM prospects and draft outreach with Codex
A demo has Codex pull CRM data, rank top accounts, and build a 13-slide deck with per-account strategy and draft outreach emails.
Make daily safe SEO fixes with a Codex automation
A scheduled Codex automation reviews analytics and SEO notes each morning, picks five safe fixes like internal links and metadata, and applies them.
Codex for research
Digging through books, papers, and data, and keeping what you learn organized.
Summarize months of notes in Logseq via CLI agent
User points Codex at the Logseq CLI docs so it can query and summarize journals and tagged job-application and project pages.
3 accounts
Automate a weekly arXiv paper triage
A weekly Codex automation searches arXiv for keywords, logs new papers to a CSV, sorts them into keep/skim/drop buckets and can check claims against Zotero.
Screen research papers against criteria
Codex reads a folder of PDFs to find articles that disagree with an argument, screens about fifty papers for a systematic review, and cleans messy CSV or Excel files.
Codex for games
Agents that play, build, and test games.
Build a racing game from a single prompt
Codex made a racing game with multiple racers, eight maps and items from one prompt, acting as designer, developer and QA tester by playing it.
4 accounts
Build game architecture and animation merging with Codex
A commenter had Codex do fundamental architecture work for their game, reading engine docs and implementing better animation merging.
Race three models to build a Counter-Strike clone
InstantDB had Codex, Opus, and Gemini each try to build a multiplayer shooter.
Also used for
Plan a vacation with a custom Codex-built website
Claire had Codex research hotels, map them on Google Maps and deploy a trip site from her phone; its browser also navigated to checkout for an item.
Recommend a hotel from client notes using Codex
A travel advisor had Codex use client notes to recommend a Belmond hotel in Italy, checking live booking engines and generating a detailed Word doc.
Produce a track in Ableton Live by talking
An MCP server that lets Codex drive Ableton Live, used to write and mix a full song from chat messages.
Design a personal website from a markdown spec
The author had Codex CLI read a design spec and iterated on it to design his personal site, and he can reuse the spec on other projects.
Generate a robot arm CAD model from one prompt
A text-to-cad skill let Codex produce a 7-DOF robot arm with kinematics, a GUI and STEP parts in one demo prompt, though not the gripper.
2 accounts
Repair formal proofs for a verified garbage collector
Codex edited files and ran builds to repair CertiGC proofs; it handled local repair well, but humans had to check that its invariants preserved the specification.
Hunt high-value Pokémon cards on eBay overnight
An engineer built a Codex agent that browses eBay listings, extracts PSA certificate numbers and cross-references known prices while he sleeps.
Agents used for similar jobs
Claude Code
140Anthropic's coding agent, including the non-coding jobs people give it.
Most often: software · sales & marketing
Cursor
32The AI code editor and its background agents.
Most often: software · work · research
Microsoft's autonomous agent.
Most often: software
The open-source personal agent often run on local models.
Most often: software · sales & marketing · content