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/helderberto/agent-skills/explain-codenpx skills add helderberto/agent-skills --skill explain-codegit clone --depth 1 https://github.com/helderberto/agent-skillsWhat 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 | $0.00062 | $0.00475 |
| Opus 5 | $0.00031 | $0.00237 |
| Sonnet 5 | $0.00012 | $0.00095 |
| Haiku 4.5 | $0.00006 | $0.00047 |
Grade A, and why
explain-code scanned grade A with 0 findings 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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
When explaining code, always include:
- Start with an analogy: Compare the code to something from everyday life
- Draw a diagram: Use ASCII art to show the flow, structure, or relationships
- Walk through the code: Explain step-by-step what happens
- Highlight a gotcha: What's a common mistake or misconception?
Keep explanations conversational. For complex concepts, use multiple analogies.
Diagram Types
Flow / Control flow:
Input -> [Validate] -> [Process] -> [Save] -> Output
|
[Error] -> Return 400
Call stack / Sequence:
Client API DB
|--request--> | |
| |--query----> |
| |<--result--- |
|<-response-- | |
Tree / Hierarchy:
App
+-- Header
| +-- Nav
+-- Main
| +-- Sidebar
| +-- Content
+-- Footer
State machine:
[Idle] --submit--> [Loading] --success--> [Done]
|
error|
[Failed] --retry--> [Loading]
Data structure:
User {
id: string
profile: Profile --> { name, avatar, bio }
posts: Post[] --> [{ id, title, body }]
}
Before / After:
Before: After:
fn() fn()
doA() doA()
doB() doB()
doC() -> helpers()
doD() doC()
doE() doD()
doE()
Error Handling
- Code references external files/modules -- read them before explaining
- Diagram too complex -- split into multiple focused diagrams, each covering one concept
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 · 77 lines · 62 tokens per session scan A bb90ba5bdb15
explain-code is a skill published in the GitHub repository helderberto/agent-skills (13 stars, last pushed 11d ago), licensed MIT. It adds 62 tokens to every session and 475 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
code-explanation
Get layered, context-aware explanations of unfamiliar code. Understand what it does, why it was written that way, and how to work with it safely.
code-review-and-quality
Conducts multi-axis code review. Use before merging any change. Use when reviewing code written by yourself, another agent, or a human. Use when you need to assess code quality across multiple dimensions before it enters the main branch.
constraint-driven-development
Establishes a project's quality bar as a written contract and stops agents quietly lowering it. Interviews the user on which dimensions matter, supplies sane default thresholds when they have no number in mind, records everything in CONSTRAINTS.md, and watches the diff for a weakened bar — new @ts-ignore or…
performance-optimization
Optimizes application performance across frontend, backend, queries, and databases. Use when performance requirements exist, when you suspect performance regressions, when Core Web Vitals or load times need improvement, when N+1 query patterns need fixing, or when profiling reveals bottlenecks.
api-and-interface-design
Guides stable API and interface design. Use when designing APIs, module boundaries, or any public interface. Use when creating REST or GraphQL endpoints, defining type contracts between modules, or establishing boundaries between frontend and backend.
code-simplification
Simplifies code for clarity. Use when refactoring code for clarity without changing behavior. Use when code works but is harder to read, maintain, or extend than it should be. Use when reviewing code that has accumulated unnecessary complexity.