jarmak-personal Codex Skill Guide
PATH Setup (CRITICAL)
Subagents run with a minimal PATH. Always include homebrew path:
export PATH="/opt/homebrew/bin:$HOME/.local/bin:$PATH" && codex <args>
Baseline Rules
Always apply these to every codex exec command:
--skip-git-repo-check— required for all commands2>/dev/null— suppresses thinking tokens (omit only if debugging)--full-auto— required when usingworkspace-writeordanger-full-accesssandbox
Command Templates
New Task
export PATH="/opt/homebrew/bin:$HOME/.local/bin:$PATH" && codex exec --skip-git-repo-check --sandbox <MODE> [options] "<prompt>" 2>/dev/null
Resume Session
export PATH="/opt/homebrew/bin:$HOME/.local/bin:$PATH" && echo "<prompt>" | codex exec --skip-git-repo-check resume --last 2>/dev/null
Note: When resuming, do not include model/sandbox flags — the session inherits its original settings. Flags must go between exec and resume.
Sandbox Modes
| Task Type | Mode | Notes |
|---|---|---|
| Analysis, review, Q&A | --sandbox read-only |
No file modifications allowed |
| Create or edit files | --sandbox workspace-write --full-auto |
Standard for most coding tasks |
| Network access needed | --sandbox danger-full-access --full-auto |
Confirm with user first |
Model Selection
When the calling agent specifies requirements, translate to flags:
| Requirement | Flag | Notes |
|---|---|---|
| Default | -m gpt-5.2-codex |
Optimized for code tasks |
| General-purpose | -m gpt-5.2 |
Non-code or mixed tasks |
| Complexity | Flag | Notes |
|---|---|---|
| Complex / multi-step | --config model_reasoning_effort="xhigh" |
Architectural decisions, large refactors |
| Standard (default) | --config model_reasoning_effort="high" |
Most coding tasks |
| Simple | --config model_reasoning_effort="medium" |
Straightforward edits |
| Trivial | --config model_reasoning_effort="low" |
Quick fixes, formatting |
If not specified, use defaults: gpt-5.2-codex with high reasoning.
Interpreting Results
Success indicators
- Codex reports files created/modified
- Output describes completed actions matching the request
- No error messages or stack traces
Failure indicators
- Non-zero exit code
- Error messages in output
- "I cannot" or "I'm unable to" language
- Partial completion ("I've started but...")
Scope creep indicators
- Mentions of "I also..." or "While I was at it..."
- Changes to files not mentioned in the original request
- Added features, tests, or documentation not requested
Redirection indicators
- Output describes different work than requested
- "Instead of X, I did Y..."
- Solving a different problem than specified
After Completion
Report to user: "You can resume this Codex session by saying 'codex resume'."
Error Handling
- If command exits non-zero: stop and report the error
- If output contains warnings: summarize and ask how to proceed
- Before
danger-full-access: confirm with user unless pre-authorized