01
What Codex is
Codex is an AI coding agent that can work inside a project: reading files, making edits, running checks, and explaining the result. In ChatGPT, it can help turn a clear task into a controlled change while you stay responsible for scope and review.
Use the name of the tool and the exact capability you have available in your environment. Do not assume it can see your private services, dashboard settings, or production data unless you explicitly verified that access.
02
When to use Codex instead of Claude
- Use Codex when you want a repository-aware implementation and verification loop
- Use Claude or ChatGPT for product thinking, copy, and turning messy goals into a task
- Use either for read-only audits before edits
- Choose based on the workflow and access you actually have, not brand claims
- Keep the same safety rules: narrow scope, checkpoint, diff, test, report
03
Audit-only prompts
Prompt 21
Inspect a feature
Copy-paste prompt
Inspect [FEATURE] in this repository. Report current behavior, relevant files, data flow, risks, and the smallest safe plan. Do not edit files or run destructive commands.
Prompt 22
Inspect Git status
Copy-paste prompt
Read-only inspection only: report branch, recent commits, changed files, untracked files, and whether the working tree is clean. Do not commit, reset, checkout, merge, push, pull, or delete.
Prompt 23
Inspect launch risk
Copy-paste prompt
Audit [APP] for auth, data access, payments, secrets, errors, mobile layout, and deployment assumptions. Separate verified findings from unknowns. Do not claim ready or secure.
04
Implementation, test, and deployment prompts
Prompt 31
Implementation
Copy-paste prompt
Implement only [CHANGE]. Preserve [BEHAVIOR]. First state the files you expect to change. After editing, show the diff summary, run [TEST], and list what was not tested.
Prompt 32
Test
Copy-paste prompt
Test [FLOW] as a user would. Cover success, empty, error, refresh, repeated action, and unauthorized cases. Report actual results and stop if the test cannot be run.
Prompt 33
Deployment check
Copy-paste prompt
Review production readiness for [CHANGE]: build, environment variables by name only, routes, redirects, migrations, and rollback. Do not deploy or claim production is verified.
05
Avoid fake PASS reports
A passing TypeScript check proves types compile; it does not prove that payments, RLS, email, mobile layout, or a real user flow work. Ask Codex to distinguish commands it ran from behavior it inferred.
A useful final report names changed files, tests actually run, tests not run, known risks, and the next manual check. If the tool cannot verify something, “unknown” is the correct result.
06
Common app-problem prompts
Prompt 51
Broken login
Copy-paste prompt
Investigate why [LOGIN SYMPTOM] occurs. Trace the flow from UI to auth response and session handling. Report evidence first; then make one minimal fix only if the cause is verified.
Prompt 52
Wrong data
Copy-paste prompt
Trace why [SCREEN] shows [WRONG RESULT]. Compare query, filters, user identity, field names, and cache. Do not change RLS or database schema without a separate audit.
Prompt 53
Slow page
Copy-paste prompt
Audit [PAGE] for the largest verified causes of slowness. Measure or identify evidence before changing code. Recommend the smallest improvement and do not add a library without explaining why.