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/engineering-os/engineering-os/eos-decidenpx skills add engineering-os/engineering-os --skill eos-decidegit clone --depth 1 https://github.com/engineering-os/engineering-osWhat 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 | $0.00024 | $0.00214 |
| Opus 5 | $0.00012 | $0.00107 |
| Sonnet 5 | $0.00005 | $0.00043 |
| Haiku 4.5 | $0.00002 | $0.00021 |
Grade A, and why
eos-decide 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
EOS Decide
Use this skill when the user wants to record, document, or preserve an engineering decision for future Codex, Cursor, Claude, or MCP sessions.
Workflow
- Extract the decision title, context, chosen option, rationale, alternatives, and tags from the user's message.
- If any required part is missing, ask concise follow-up questions.
- Call
eos_decide. - Confirm what was recorded and where future agents should recall it.
Tool Pattern
eos_decide {
"title": "<decision title>",
"context": "<why this decision is needed>",
"decision": "<chosen option>",
"rationale": "<why this option was chosen>",
"alternatives": [{ "option": "<alternative>", "proscons": "<tradeoffs>" }],
"tags": ["<area>", "<topic>"]
}
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 · 29 lines · 24 tokens per session scan A 167f8d19c8cc
eos-decide is a skill published in the GitHub repository engineering-os/engineering-os (35 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 24 tokens to every session and 214 once invoked, about $0.0001 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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