Change Codex System Prompt
# How to Change Codex System Prompt
Codex has a built-in instruction layer, but you can replace it with your own system prompt using `model_instructions_file` in your Codex config.
This is useful when you want Codex to behave less like a generic coding assistant and more like a consistent coding agent inside your workspace.
## Adding a Custom System Prompt to Codex
Create a markdown file for your custom Codex instructions.
Example:when to use it
Community prompt sourced from the open-source GitHub repo Austin1serb/agents-md (no explicit license). A "Change Codex System Prompt" style prompt — adapt the placeholders and specifics to your task. Imported as-is and not independently retested here, so check the output before relying on it.
tags
productivitycommunitydeveloper
source
Austin1serb/agents-md · no explicit license
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