Codex

Run uvx jes login first. See Setup.

Install

uvx jes codex-settings

Copy the hooks object it prints into ~/.codex/hooks.json. Codex ignores a hook until you trust its exact text with /hooks.

uvx jes codex-settings

{
  "hooks": {
    "UserPromptSubmit": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "uvx jes@0.0.1 codex-hook",
            "timeout": 60
          }
        ]
      }
    ],
    "PreToolUse": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "uvx jes@0.0.1 codex-hook",
            "timeout": 60
          }
        ]
      }
    ],
    "PostToolUse": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "uvx jes@0.0.1 codex-hook",
            "timeout": 60
          }
        ]
      }
    ],
    "Stop": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "uvx jes@0.0.1 codex-hook",
            "timeout": 60
          }
        ]
      }
    ]
  }
}

What each hook does

Event	Stage	If jes blocks
UserPromptSubmit	input	Returns decision: block with the refusal as the reason.
PreToolUse	tool_call	Denies the call. The tool does not run.
PostToolUse	tool_result	Returns decision: block, so the model reads the refusal instead of the result.
Stop	output	Checks last_assistant_message and continues the turn with the refusal.

Limits

• PostToolUse fires after the command has run. It does not undo it. Codex doesn't apply updatedToolOutput, so jes uses decision: block instead.
• Stop does not change text already on screen. A second Stop with stop_hook_active set is skipped, so a refusal can't loop.