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.
/plugin marketplace add ARCASSystems/FounderOSnpx agentmods add plugins/arcassystems/founderos/marketplacegit clone --depth 1 https://github.com/ARCASSystems/FounderOSGrade A, and why
founder-os-marketplace 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 2d 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
{
"name": "founder-os-marketplace",
"owner": {
"name": "ARCAS Systems",
"email": "[email protected]",
"url": "https://github.com/ARCASSystems"
},
"metadata": {
"description": "Founder OS plugin and operating-system tools for owners",
"version": "1.54.3"
},
"plugins": [
{
"name": "founder-os",
"source": {
"source": "github",
"repo": "ARCASSystems/FounderOS"
},
"description": "An operating system with your first team already on it: five named digital employees with written job descriptions, gated until you grade their runs, and a brain that keeps everything you tell it and invents nothing. 95 skills, 45 commands, six role modes. The wizard interviews you and models your working life in plain markdown you own: clients, pipeline, decisions, cadence, voice, brand. No server, no key, no git required - ZIP install, one Claude plan. Files any AI can read: the model is the part you swap, the brain is the part you keep",
"version": "1.54.3",
"strict": true
}
]
}What ships with it
1 file beside marketplace.json 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.
- 2d ago First seen · 24 lines scan A 0d8900cfd7f5
founder-os-marketplace is a plugin published in the GitHub repository ARCASSystems/FounderOS (5 stars, last pushed 18d ago), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. 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 2026-08-31.
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