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 firstsun-dev/skills --skill openspec-onboardgit clone --depth 1 https://github.com/firstsun-dev/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/firstsun-dev/skills/openspec-onboard)<a href="https://agentmods.dev/skills/firstsun-dev/skills/openspec-onboard"><img src="https://agentmods.dev/badge/skills/firstsun-dev/skills/openspec-onboard/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/firstsun-dev/skills/openspec-onboard"><img src="https://agentmods.dev/badge/skills/firstsun-dev/skills/openspec-onboard.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 | $0.00043 | $0.04245 |
| Opus 5.5 | $0.00017 | $0.01698 |
| Sonnet 5.5 | $0.00009 | $0.00849 |
| Haiku 4.5 | $0.00004 | $0.00424 |
Grade A, and why
openspec-onboard 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 25d 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
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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.
- 25d ago Changed · +9 lines · +17 tokens per session 9066a948a3ca
- 1mo ago First seen · 561 lines · 26 tokens per session scan A 9add352e1582
openspec-onboard is a skill published in the GitHub repository firstsun-dev/skills (5 stars, last pushed 6d ago), with no licence file. It adds 43 tokens to every session and 4,245 once invoked, about $0.0002 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 2026-09-15.
Other skills, from other repositories
study
Guide structured learning for a topic by diagnosing current level, defining stage goals, building a learning path, generating practice, and running review loops. Use when the user wants to learn something step by step, start from zero, build a study plan, prepare for an exam or skill, get guided practice, or continue…
eli5
Create a simple, picture-first explanation of a topic, defaulting to self-contained HTML. Use when the user says ELI5, asks to explain something like they are five, or wants a visual explanation with very few words; do not use for ordinary concise explanations that do not ask for this style.
learning-assistant
An interactive study assistant that turns a learning goal into a structured plan and guides the learner through it. It uses a local knowledge graph, a connected record of topics and learning state, as its long-term memory.
project-learner
An interactive project-teaching assistant that explains a codebase, files, or underlying technologies and records the lessons in Markdown logs. It can continue from earlier learning records.
subject-learning-assistant
A structured learning assistant that turns study material into a plan of subjects, topics, and individual concepts. It can guide lessons and track progress using a connected knowledge map.
pinpoint-lesson
Compose a long-form pin-point lesson from one paper and register it as a Zotero child note. Use when the user provides a PDF or paper title and wants a math-grounded, idea-genealogy, fundamental-why analysis rather than a quick summary. Contrast with the summary skill, which produces a shorter overview note.