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 skills add personamanagmentlayer/pcl --skill webassembly-expertgit clone --depth 1 https://github.com/personamanagmentlayer/pclWrote 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/personamanagmentlayer/pcl/webassembly-expert)<a href="https://agentmods.dev/skills/personamanagmentlayer/pcl/webassembly-expert"><img src="https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/webassembly-expert/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/personamanagmentlayer/pcl/webassembly-expert"><img src="https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/webassembly-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00069 | $0.01211 |
| Opus 5.5 | $0.00028 | $0.00484 |
| Sonnet 5.5 | $0.00014 | $0.00242 |
| Haiku 4.5 | $0.00007 | $0.00121 |
Grade A, and why
webassembly-expert 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.
How it starts
The opening of the file, as written. The whole thing — 186 lines — stays where its author put it; the contents beside it link to each section on GitHub.
WebAssembly Expert
Create production-ready WebAssembly modules for web and server environments with optimal performance and seamless JavaScript integration.
Learning Objectives
- Master WebAssembly module development and compilation
- Build high-performance WASM applications from Rust and C++
- Implement WASI for system-level capabilities
- Optimize WASM for size and execution speed
- Integrate WASM with JavaScript and web browsers
Prerequisites
- Strong Rust or C++ programming skills
- Understanding of low-level systems programming
- Knowledge of web technologies (JavaScript, browsers)
- Familiarity with compilation toolchains
Core Concepts
WebAssembly (WASM)
Binary instruction format designed as portable compilation target for high-level languages. Provides near-native performance in web browsers and enables code reuse across platforms.
WASI (WebAssembly System Interface)
System interface specification enabling WASM to run outside browsers with access to system resources (files, network, environment) in a secure, sandboxed manner.
Memory Management
Linear memory model where WASM modules access contiguous byte arrays. Requires careful management of memory allocation, deallocation, and sharing between WASM and JavaScript.
Compilation Targets
Languages like Rust, C++, C, Go, and AssemblyScript can compile to WASM. Each provides different toolchains (rustc, Emscripten, TinyGo) with varying levels of optimization.
JavaScript Interop
Bidirectional communication between WASM and JavaScript through imported/exported functions, shared memory, and typed arrays. Requires careful data marshalling and type conversions.
Best Practices
Performance Optimization
- Minimize data copying between JavaScript and WASM
- Use shared memory (SharedArrayBuffer) for large datasets
- Batch operations to reduce boundary crossings
- Optimize for WASM instruction set (SIMD when available)
- Profile hot paths and optimize critical loops
- Use appropriate numeric types (i32, f32 for better performance)
- Enable compiler optimizations (opt-level, lto)
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 · 186 lines · 69 tokens per session scan A 24fac9797e44
webassembly-expert is a skill published in the GitHub repository personamanagmentlayer/pcl (43 stars, last pushed 12d ago), licensed Apache-2.0. It adds 69 tokens to every session and 1,211 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-09-05.
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