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 fcsouza/agent-skills --skill foundry-vtt-module-devgit clone --depth 1 https://github.com/fcsouza/agent-skillsWrote 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/fcsouza/agent-skills/foundry-vtt-module-dev)<a href="https://agentmods.dev/skills/fcsouza/agent-skills/foundry-vtt-module-dev"><img src="https://agentmods.dev/badge/skills/fcsouza/agent-skills/foundry-vtt-module-dev/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/fcsouza/agent-skills/foundry-vtt-module-dev"><img src="https://agentmods.dev/badge/skills/fcsouza/agent-skills/foundry-vtt-module-dev.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 | $0.00216 | $0.12927 |
| Opus 5.5 | $0.00086 | $0.05171 |
| Sonnet 5.5 | $0.00043 | $0.02585 |
| Haiku 4.5 | $0.00022 | $0.01293 |
Grade A, and why
foundry-vtt-module-dev 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.
The source is not reproduced here
Licensed GPL-3.0
The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What ships with it
32 files 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.
- boilerplate/actor-sheet.mjs 4.7 KB runs code
- boilerplate/main.mjs 2.7 KB runs code
- boilerplate/module.json 1.1 KB
- boilerplate/package.json 592 B
- boilerplate/rollup.config.mjs 1.1 KB runs code
- boilerplate/sheet.hbs 5.0 KB
- boilerplate/socket-handler.mjs 4.8 KB runs code
- boilerplate/type-data-model.mjs 4.6 KB runs code
- boilerplate/vite.config.mjs 1.5 KB runs code
- references/accessibility.md 9.0 KB
- references/active-effects-v2.md 21 KB
- references/adventure-documents.md 15 KB
- references/application-v2.md 38 KB
- references/audio-and-macros.md 8.9 KB
- references/build-pipeline.md 14 KB
- references/canvas-and-pixi.md 33 KB
- references/chat-and-ui.md 29 KB
- references/combat-and-tokens.md 20 KB
- references/document-model.md 36 KB
- references/handlebars-and-templates.md 17 KB
- references/hooks-and-settings.md 25 KB
- references/measured-templates.md 9.9 KB
- references/migration-guide.md 13 KB
- references/module-subtypes.md 12 KB
- references/permissions-and-ownership.md 17 KB
- references/regions-and-grid.md 13 KB
- references/scene-levels.md 18 KB
- references/sockets-rolls-packs.md 23 KB
- references/testing-with-quench.md 9.1 KB
- references/v14-migration.md 23 KB
- references/vision-and-lighting.md 11 KB
- templates/module-checklist.md 3.4 KB
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 Changed · +94 lines · +38 tokens per session 28c51828c941
- 1mo ago First seen · 835 lines · 178 tokens per session scan A 5c6f02c3a3b4
foundry-vtt-module-dev is a skill published in the GitHub repository fcsouza/agent-skills (22 stars, last pushed 6d ago), licensed GPL-3.0. It adds 216 tokens to every session and 12,927 once invoked, about $0.0009 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 2026-08-30.
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