Codex Code Review Skill
Trigger Conditions
Triggered when user input contains:
- "代码审核", "代码审查", "审查代码", "审核代码"
- "review", "code review", "review code", "codex 审核"
- "帮我审核", "检查代码", "审一下", "看看代码"
Core Concept: Intention vs Implementation
Running
codex review --uncommitted
alone only shows AI "what was done (Implementation)".
Recording intention first tells AI "what you wanted to do (Intention)".
"Code changes + intention description" as combined input is the most effective way to improve AI code review quality.
Skill Architecture
This skill operates in two phases:
- Preparation Phase (current context): Check working directory, update CHANGELOG
- Review Phase (isolated context): Invoke Task tool to execute Lint + codex review (using context: fork to reduce context waste)
Execution Steps
0. [First] Check Working Directory Status
bash
git diff --name-only && git status --short
Decide review mode based on output:
- Has uncommitted changes → Continue with steps 1-4 (normal flow)
- Clean working directory → Directly invoke codex-runner:
codex review --commit HEAD
1. [Mandatory] Check if CHANGELOG is Updated
Before any review, must check if CHANGELOG.md contains description of current changes.
bash
# Check if CHANGELOG.md is in uncommitted changes
git diff --name-only | grep -E "(CHANGELOG|changelog)"
If CHANGELOG is not updated, you must automatically perform the following (don't ask user to do it manually):
- Analyze changes: Run and to get complete changes
- Auto-generate CHANGELOG entry: Generate compliant entry based on code changes
- Write to CHANGELOG.md: Use Edit tool to insert entry at top of section
- Continue review flow: Immediately proceed to next steps after CHANGELOG update
Auto-generated CHANGELOG entry format:
markdown
## [Unreleased]
### Added / Changed / Fixed
- Feature description: what problem was solved or what functionality was implemented
- Affected files: main modified files/modules
Example - Auto-generation Flow:
1. Detected CHANGELOG not updated
2. Run git diff --stat, found handlers/responses.go modified (+88 lines)
3. Run git diff to analyze details: added CompactHandler function
4. Auto-generate entry:
### Added
- Added `/v1/responses/compact` endpoint for conversation context compression
- Supports multi-channel failover and request body size limits
5. Use Edit tool to write to CHANGELOG.md
6. Continue with lint and codex review
2. [Critical] Stage All New Files
Before invoking codex review, must add all new files (untracked files) to git staging area, otherwise codex will report P1 error.
bash
# Check for new files
git status --short | grep "^??"
If there are new files, automatically execute:
bash
# Safely stage all new files (handles empty list and special filenames)
git ls-files --others --exclude-standard -z | while IFS= read -r -d '' f; do git add -- "$f"; done
Explanation:
- uses null character to separate filenames, correctly handles filenames with spaces/newlines
- reads filenames one by one
- uses separator, correctly handles filenames starting with
- When no new files exist, loop body doesn't execute, safely skipped
- This won't stage modified files, only handles new files
- codex needs files to be tracked by git for proper review
3. Evaluate Task Difficulty and Invoke codex-runner
Count change scale:
bash
# Count number of changed files and lines of code
git diff --stat | tail -1
Difficulty Assessment Criteria:
Difficult Tasks (meets any condition):
- Modified files ≥ 10
- Total code changes (insertions + deletions) ≥ 500 lines
- Single metric: insertions ≥ 300 lines OR deletions ≥ 300 lines
- Involves core architecture/algorithm changes
- Cross-module refactoring
- Config:
model_reasoning_effort=xhigh
, timeout 30 minutes
Normal Tasks (other cases):
- Config:
model_reasoning_effort=high
, timeout 10 minutes
Evaluation Method:
You MUST parse the
output correctly to determine difficulty:
bash
# Get the summary line (last line of git diff --stat)
git diff --stat | tail -1
# Example outputs:
# "20 files changed, 342 insertions(+), 985 deletions(-)"
# "1 file changed, 50 insertions(+)" # No deletions
# "3 files changed, 120 deletions(-)" # No insertions
Parsing Rules:
- Extract file count from "X file(s) changed" (handle both "1 file" and "N files")
- Extract insertions from "Y insertion(s)(+)" if present (handle both "1 insertion" and "N insertions"), otherwise 0
- Extract deletions from "Z deletion(s)(-)" if present (handle both "1 deletion" and "N deletions"), otherwise 0
- Calculate total changes = insertions + deletions
Important Edge Cases:
- Single file: (singular form)
- No insertions: Git omits entirely → treat as 0
- No deletions: Git omits entirely → treat as 0
- Pure rename: May show
"0 insertions(+), 0 deletions(-)"
or omit both
Decision Logic (ANY condition triggers xhigh):
- IF file_count >= 10 → xhigh
- IF total_changes >= 500 → xhigh
- IF insertions >= 300 → xhigh
- IF deletions >= 300 → xhigh
- ELSE → high
Example Cases:
- ✅ "20 files changed, 342 insertions(+), 985 deletions(-)" → xhigh (files=20≥10, total=1327≥500, deletions=985≥300)
- ✅ "5 files changed, 600 insertions(+), 50 deletions(-)" → xhigh (total=650≥500, insertions=600≥300)
- ✅ "12 files changed, 100 insertions(+), 50 deletions(-)" → xhigh (files=12≥10)
- ✅ "1 file changed, 400 deletions(-)" → xhigh (deletions=400≥300)
- ❌ "3 files changed, 150 insertions(+), 80 deletions(-)" → high (all conditions fail)
- ❌ "1 file changed, 50 insertions(+)" → high (no deletions, total=50<500)
Invoke codex-runner Subtask:
Use Task tool to invoke codex-runner, passing complete command (including Lint + codex review):
Task parameters:
- subagent_type: Bash
- description: "Execute Lint and codex review"
- timeout: 1800000 (30 minutes for difficult tasks) or 600000 (10 minutes for normal tasks)
- prompt: Choose corresponding command based on project type and difficulty
Go project - Difficult task:
go fmt ./... && go vet ./... && codex review --uncommitted --config model_reasoning_effort=xhigh
(timeout: 1800000)
Go project - Normal task:
go fmt ./... && go vet ./... && codex review --uncommitted --config model_reasoning_effort=high
(timeout: 600000)
Node project - Difficult task:
npm run lint:fix && codex review --uncommitted --config model_reasoning_effort=xhigh
(timeout: 1800000)
Node project - Normal task:
npm run lint:fix && codex review --uncommitted --config model_reasoning_effort=high
(timeout: 600000)
Python project - Difficult task:
black . && ruff check --fix . && codex review --uncommitted --config model_reasoning_effort=xhigh
(timeout: 1800000)
Python project - Normal task:
black . && ruff check --fix . && codex review --uncommitted --config model_reasoning_effort=high
(timeout: 600000)
Clean working directory:
codex review --commit HEAD --config model_reasoning_effort=high
(timeout: 600000)
4. Self-Correction
If Codex finds Changelog description inconsistent with code logic:
- Code error → Fix code
- Description inaccurate → Update Changelog
Complete Review Protocol
- [GATE] Check CHANGELOG - Auto-generate and write if not updated (leverage current context to understand change intention)
- [PREPARE] Stage Untracked Files - Add all new files to git staging area (avoid codex P1 error)
- [EXEC] Task → Lint + codex review - Invoke Task tool to execute Lint and codex (isolated context, reduce waste)
- [FIX] Self-Correction - Fix code or update description when intention ≠ implementation
Codex Review Command Reference
Basic Syntax
bash
codex review [OPTIONS] [PROMPT]
Note:
parameter cannot be used with
,
, or
.
Common Options
| Option | Description | Example |
|---|
| Review all uncommitted changes in working directory (staged + unstaged + untracked) | codex review --uncommitted
|
| Review changes relative to specified base branch | |
| Review changes introduced by specified commit | codex review --commit HEAD
|
| Optional commit title, displayed in review summary | codex review --uncommitted --title "feat: add JSON parser"
|
| Override configuration values | codex review --uncommitted -c model="o3"
|
Usage Examples
bash
# 1. Review all uncommitted changes (most common)
codex review --uncommitted
# 2. Review latest commit
codex review --commit HEAD
# 3. Review specific commit
codex review --commit abc1234
# 4. Review all changes in current branch relative to main
codex review --base main
# 5. Review changes in current branch relative to develop
codex review --base develop
# 6. Review with title (title shown in review summary)
codex review --uncommitted --title "fix: resolve JSON parsing errors"
# 7. Review using specific model
codex review --uncommitted -c model="o3"
Important Limitations
- , , are mutually exclusive, cannot be used together
- parameter is mutually exclusive with the above three options
- Must be executed in a git repository directory
Important Notes
- Ensure execution in git repository directory
- Timeout automatically adjusted based on task difficulty:
- Difficult tasks: 30 minutes ()
- Normal tasks: 10 minutes ()
- codex command must be properly configured and logged in
- codex automatically processes in batches for large changes
- CHANGELOG.md must be in uncommitted changes, otherwise Codex cannot see intention description
Design Rationale
Why separate contexts?
- CHANGELOG update needs current context: Understanding user's previous conversation and task intention to generate accurate change description
- Codex review doesn't need conversation history: Only needs code changes and CHANGELOG, more efficient to run independently
- Reduce token consumption: codex review as independent subtask, doesn't carry irrelevant conversation context