Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/ValorVie/custom-skillsnpx agentmods add skills/valorvie/custom-skills/error-code-guideWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/valorvie/custom-skills/error-code-guide)<a href="https://agentmods.dev/skills/valorvie/custom-skills/error-code-guide"><img src="https://agentmods.dev/badge/skills/valorvie/custom-skills/error-code-guide.svg" alt="Measured on agentmods" height="20"></a>What 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 5.1 | $0.00058 | $0.01867 |
| Opus 5 | $0.00029 | $0.00933 |
| Sonnet 5 | $0.00012 | $0.00373 |
| Haiku 4.5 | $0.00006 | $0.00187 |
Grade A, and why
error-code-guide 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 5d 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.
How it starts
The opening of the file, as written. The whole thing — 279 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Error Code Guide
Language: English | 繁體中文
Version: 1.0.0 Last Updated: 2025-12-30 Applicability: Claude Code Skills
Core Standard: This skill implements Error Code Standards. For comprehensive methodology documentation, refer to the core standard.
Purpose
This skill helps design consistent error codes following the standard format, enabling better debugging, monitoring, and user experience.
Quick Reference
Error Code Format
<PREFIX>_<CATEGORY>_<NUMBER>
| Component | Description | Example |
|---|---|---|
| PREFIX | Application/service identifier | AUTH, PAY, USR |
| CATEGORY | Error category | VAL, SYS, BIZ |
| NUMBER | Unique numeric identifier | 001, 100, 404 |
Examples
AUTH_VAL_001 → Authentication validation error
PAY_SYS_503 → Payment system unavailable
USR_BIZ_100 → User business rule violation
API_NET_408 → API network timeout
Error Categories
| Category | Full Name | Description | HTTP Status |
|---|---|---|---|
| VAL | Validation | Client input validation failures | 400 |
| BIZ | Business | Business rule violations | 422 |
| SYS | System | Internal system failures | 500 |
| NET | Network | Communication failures | 502/503/504 |
| AUTH | Auth | Security-related errors | 401/403 |
Category Code Ranges
| Range | Description | Example |
|---|---|---|
| *_VAL_001-099 | Field validation | Missing required field |
| *_VAL_100-199 | Format validation | Invalid email format |
| *_VAL_200-299 | Constraint validation | Password too short |
| *_BIZ_001-099 | State violations | Order already cancelled |
| *_BIZ_100-199 | Rule violations | Cannot return after 30 days |
| *_BIZ_200-299 | Limit violations | Daily limit exceeded |
| *_AUTH_001-099 | Authentication | Invalid credentials |
| *_AUTH_100-199 | Authorization | Insufficient permissions |
| *_AUTH_200-299 | Token/session | Token expired |
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.
- 5d ago First seen · 279 lines · 58 tokens per session scan A 010d3cff8829
error-code-guide is a skill published in the GitHub repository ValorVie/custom-skills (5 stars, last pushed 8d ago), licensed MIT. It adds 58 tokens to every session and 1,867 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 2026-09-03.
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