Borrowing it
Nothing to install: this file belongs to aphrody-code/bxc. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/aphrody-code/bxc/main/.agents/skills/m15-anti-pattern/SKILL.mdgit clone --depth 1 https://github.com/aphrody-code/bxcWrote 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/aphrody-code/bxc/m15-anti-pattern)<a href="https://agentmods.dev/skills/aphrody-code/bxc/m15-anti-pattern"><img src="https://agentmods.dev/badge/skills/aphrody-code/bxc/m15-anti-pattern/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/aphrody-code/bxc/m15-anti-pattern"><img src="https://agentmods.dev/badge/skills/aphrody-code/bxc/m15-anti-pattern.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00101 | $0.01195 |
| Opus 5.5 | $0.00040 | $0.00478 |
| Sonnet 5.5 | $0.00020 | $0.00239 |
| Haiku 4.5 | $0.00010 | $0.00120 |
Grade A, and why
m15-anti-pattern 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 1mo 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.
This is a copy
100% identical to m15-anti-pattern — 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 — 161 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Anti-Patterns
Layer 2: Design Choices
Core Question
Is this pattern hiding a design problem?
When reviewing code:
- Is this solving the symptom or the cause?
- Is there a more idiomatic approach?
- Does this fight or flow with Rust?
Anti-Pattern → Better Pattern
| Anti-Pattern | Why Bad | Better |
|---|---|---|
.clone() everywhere |
Hides ownership issues | Proper references or ownership |
.unwrap() in production |
Runtime panics | ?, expect, or handling |
Rc when single owner |
Unnecessary overhead | Simple ownership |
unsafe for convenience |
UB risk | Find safe pattern |
OOP via Deref |
Misleading API | Composition, traits |
| Giant match arms | Unmaintainable | Extract to methods |
String everywhere |
Allocation waste | &str, Cow<str> |
Ignoring #[must_use] |
Lost errors | Handle or let _ = |
Thinking Prompt
When seeing suspicious code:
-
Is this symptom or cause?
- Clone to avoid borrow? → Ownership design issue
- Unwrap "because it won't fail"? → Unhandled case
-
What would idiomatic code look like?
- References instead of clones
- Iterators instead of index loops
- Pattern matching instead of flags
-
Does this fight Rust?
- Fighting borrow checker → restructure
- Excessive unsafe → find safe pattern
Trace Up ↑
To design understanding:
"Why does my code have so many clones?"
↑ Ask: Is the ownership model correct?
↑ Check: m09-domain (data flow design)
↑ Check: m01-ownership (reference patterns)
| Anti-Pattern | Trace To | Question |
|---|---|---|
| Clone everywhere | m01-ownership | Who should own this data? |
| Unwrap everywhere | m06-error-handling | What's the error strategy? |
| Rc everywhere | m09-domain | Is ownership clear? |
| Fighting lifetimes | m09-domain | Should data structure change? |
Trace Down ↓
To implementation (Layer 1):
"Replace clone with proper ownership"
↓ m01-ownership: Reference patterns
↓ m02-resource: Smart pointer if needed
"Replace unwrap with proper handling"
↓ m06-error-handling: ? operator
↓ m06-error-handling: expect with message
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 161 lines · 101 tokens per session scan A bcbb49e47b76
m15-anti-pattern is a skill published in the GitHub repository aphrody-code/bxc (3 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 101 tokens to every session and 1,195 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to m15-anti-pattern, differing in 0 lines, and is treated as a copy.
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