Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/keyuchen21/agentic-engineering-handbook/code-reviewnpx skills add keyuchen21/agentic-engineering-handbook --skill code-reviewgit clone --depth 1 https://github.com/keyuchen21/agentic-engineering-handbookWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00035 | $0.01103 |
| Opus 5 | $0.00017 | $0.00551 |
| Sonnet 5 | $0.00007 | $0.00221 |
| Haiku 4.5 | $0.00003 | $0.00110 |
Grade A, and why
code-review scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Runs shell commandslowCapability
Expected in a hook, worth knowing in a rule or an instructions file.
os.system(f"ls {user_input}") This is a copy
100% identical to code-review — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 158 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Code Review Skill
You now have expertise in conducting comprehensive code reviews. Follow this structured approach:
Review Checklist
1. Security (Critical)
Check for:
- Injection vulnerabilities: SQL, command, XSS, template injection
- Authentication issues: Hardcoded credentials, weak auth
- Authorization flaws: Missing access controls, IDOR
- Data exposure: Sensitive data in logs, error messages
- Cryptography: Weak algorithms, improper key management
- Dependencies: Known vulnerabilities (check with
npm audit,pip-audit)
# Quick security scans
npm audit # Node.js
pip-audit # Python
cargo audit # Rust
grep -r "password\|secret\|api_key" --include="*.py" --include="*.js"
2. Correctness
Check for:
- Logic errors: Off-by-one, null handling, edge cases
- Race conditions: Concurrent access without synchronization
- Resource leaks: Unclosed files, connections, memory
- Error handling: Swallowed exceptions, missing error paths
- Type safety: Implicit conversions, any types
3. Performance
Check for:
- N+1 queries: Database calls in loops
- Memory issues: Large allocations, retained references
- Blocking operations: Sync I/O in async code
- Inefficient algorithms: O(n^2) when O(n) possible
- Missing caching: Repeated expensive computations
4. Maintainability
Check for:
- Naming: Clear, consistent, descriptive
- Complexity: Functions > 50 lines, deep nesting > 3 levels
- Duplication: Copy-pasted code blocks
- Dead code: Unused imports, unreachable branches
- Comments: Outdated, redundant, or missing where needed
5. Testing
Check for:
- Coverage: Critical paths tested
- Edge cases: Null, empty, boundary values
- Mocking: External dependencies isolated
- Assertions: Meaningful, specific checks
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 158 lines · 35 tokens per session scan A a64c8c43b496
code-review is a skill published in the GitHub repository keyuchen21/agentic-engineering-handbook (183 stars, last pushed 29d ago), licensed MIT. It adds 35 tokens to every session and 1,103 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). It is 100% identical to code-review, differing in 0 lines, and is treated as a copy.
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