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.
git clone --depth 1 https://github.com/ratnesh-maurya/cursor-claude-personasWrote 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/rules/ratnesh-maurya/cursor-claude-personas/rules-can-decode)<a href="https://agentmods.dev/rules/ratnesh-maurya/cursor-claude-personas/rules-can-decode"><img src="https://agentmods.dev/badge/rules/ratnesh-maurya/cursor-claude-personas/rules-can-decode/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/rules/ratnesh-maurya/cursor-claude-personas/rules-can-decode"><img src="https://agentmods.dev/badge/rules/ratnesh-maurya/cursor-claude-personas/rules-can-decode.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 | $0.00014 | $0.00401 |
| Opus 5.5 | $0.00006 | $0.00160 |
| Sonnet 5.5 | $0.00003 | $0.00080 |
| Haiku 4.5 | $0.00001 | $0.00040 |
Grade A, and why
can-decode 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.
What it actually says
Checking if a video can be decoded
Use Mediabunny to check if a video can be decoded by the browser before attempting to play it.
The canDecode() function
This function can be copy-pasted into any project.
import { Input, ALL_FORMATS, UrlSource } from "mediabunny";
export const canDecode = async (src: string) => {
const input = new Input({
formats: ALL_FORMATS,
source: new UrlSource(src, {
getRetryDelay: () => null,
}),
});
try {
await input.getFormat();
} catch {
return false;
}
const videoTrack = await input.getPrimaryVideoTrack();
if (videoTrack && !(await videoTrack.canDecode())) {
return false;
}
const audioTrack = await input.getPrimaryAudioTrack();
if (audioTrack && !(await audioTrack.canDecode())) {
return false;
}
return true;
};
Usage
const src = "https://remotion.media/video.mp4";
const isDecodable = await canDecode(src);
if (isDecodable) {
console.log("Video can be decoded");
} else {
console.log("Video cannot be decoded by this browser");
}
Using with Blob
For file uploads or drag-and-drop, use BlobSource:
import { Input, ALL_FORMATS, BlobSource } from "mediabunny";
export const canDecodeBlob = async (blob: Blob) => {
const input = new Input({
formats: ALL_FORMATS,
source: new BlobSource(blob),
});
// Same validation logic as above
};
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 · 76 lines · 14 tokens per session scan A fb3f9933e451
can-decode is a cursor rule published in the GitHub repository ratnesh-maurya/cursor-claude-personas (12 stars, last pushed 7mo ago), licensed MIT. It adds 14 tokens to every session and 401 once invoked, about $0.0001 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 2026-09-03.
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