ST3GG is an open-source steganography toolkit that hides and detects secret data in files such as images, audio, documents, and network packets. People use it through a browser-based site or Python command-line, text-interface, and web-interface applications for encoding, decoding, and steganalysis. The catalogue skill extends agent workflows around this toolkit.
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/elder-plinius/st3gg/stegg-clinpx skills add elder-plinius/ST3GG --skill stegg-cligit clone --depth 1 https://github.com/elder-plinius/ST3GGWrote 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/elder-plinius/st3gg/stegg-cli)<a href="https://agentmods.dev/skills/elder-plinius/st3gg/stegg-cli"><img src="https://agentmods.dev/badge/skills/elder-plinius/st3gg/stegg-cli.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 | $0.00106 | $0.00932 |
| Opus 5 | $0.00053 | $0.00466 |
| Sonnet 5 | $0.00021 | $0.00186 |
| Haiku 4.5 | $0.00011 | $0.00093 |
Grade A, and why
stegg-cli 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 4d 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.
The source is not reproduced here
Licensed AGPL-3.0
The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
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.
- 4d ago First seen · 107 lines · 106 tokens per session scan A 139aea42ecdd
stegg-cli is a skill published in the GitHub repository elder-plinius/ST3GG (1,758 stars, last pushed 2mo ago), licensed AGPL-3.0. It adds 106 tokens to every session and 932 once invoked, about $0.0005 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.
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