ninjaproger Codex Agent
Quick Start
# Ensure skills are installed, then run:
codex exec --full-auto --cd [PROJECT_ROOT] \
"Use the tca-developer skill to implement [FEATURE_NAME]. ..."
Sibling Skill Paths
This skill is part of a plugin. The other skills (tca-developer, tca-architect, ios-simulator)
are installed in the same plugin directory as this skill.
Derive their absolute paths by replacing the last path component of this skill's base directory:
- This skill's base:
.../skills/codex-agent/ - tca-developer:
.../skills/tca-developer/ - ios-simulator:
.../skills/ios-simulator/
Use the resolved absolute path wherever <SKILL_PATH> appears below.
Codex registers skills by file path in ~/.codex/config.toml. When the path points to the source
skill directory, it always reads the latest SKILL.md from disk — no explicit update step needed.
To check which skills are registered, open an interactive Codex session and run /skills.
To install a missing skill, open an interactive Codex session and run $skill-installer install <SKILL_PATH>.
Run
TCA Feature Development
codex exec --full-auto --cd [PROJECT_ROOT] \
"Use the tca-developer skill to implement [FEATURE_NAME]. \
Explore Sources/, use [REFERENCE_FEATURE] as style reference. \
When implementation is done, validate by running: [TEST_COMMAND]. \
Report test results and a summary of files created."
Where [TEST_COMMAND] is the project's test command, e.g.:
xcodebuild test -project MyApp.xcodeproj -scheme MyAppTests \
-destination 'platform=iOS Simulator,name=iPhone 17 Pro' -skipMacroValidation
Identify [REFERENCE_FEATURE] by listing Sources/ and picking the nearest existing feature.
iOS Simulator Automation
The ios_sim.py script is at <ios-simulator-skill-path>/scripts/ios_sim.py. Resolve this path
from this skill's base directory before running.
codex exec --full-auto \
"Use the ios-simulator skill to [TASK]. \
Simulator script: <IOS_SIMULATOR_SKILL_PATH>/scripts/ios_sim.py. Print a summary when done."
TCA Feature Development + Simulator Verification
codex exec --full-auto --cd [PROJECT_ROOT] \
"Use the tca-developer skill to implement [FEATURE_NAME]. \
Validate with: [TEST_COMMAND]. \
Then use the ios-simulator skill to verify the UI. \
Simulator script: <IOS_SIMULATOR_SKILL_PATH>/scripts/ios_sim.py. Print a summary."
Tips
--full-auto=--sandbox workspace-write --ask-for-approval never— Codex edits files and runs shell commands without pausing- Use
--output-last-message /tmp/result.mdfor long runs, then read the file to review the summary - For simulator tasks, provide the UDID or tell Codex to run
ios_sim.py listfirst codex exec resume --lastcontinues the previous session
References
references/codex-cli.md— Full flag reference forcodex exec. Read when you need non-default flags (output format, sandbox mode, session resume).