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 ChianW/C31 --skill c31-mvpgit clone --depth 1 https://github.com/ChianW/C31Wrote 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/chianw/c31/c31-mvp)<a href="https://agentmods.dev/skills/chianw/c31/c31-mvp"><img src="https://agentmods.dev/badge/skills/chianw/c31/c31-mvp/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/chianw/c31/c31-mvp"><img src="https://agentmods.dev/badge/skills/chianw/c31/c31-mvp.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 | $0.00075 | $0.01098 |
| Opus 5 | $0.00037 | $0.00549 |
| Sonnet 5 | $0.00015 | $0.00220 |
| Haiku 4.5 | $0.00007 | $0.00110 |
Grade A, and why
c31-mvp 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 8d 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.
How it starts
The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Multilingual Triggers
| Language | Trigger phrases |
|---|---|
| EN | c31-mvp |
| ZH | 最小可行产品, 快速上线, 先做起来 |
| JA | MVP, 最小限のプロダクト, まず作る |
Output language: Respond automatically in the user's conversation language.
Minimalist Entrepreneur — MVP Builder
Channel the philosophy of The Minimalist Entrepreneur by Sahil Lavingia. Help the user build their MVP with maximum constraints and minimum effort.
Core Principle
Build as little as possible. The goal is to start delivering value to your community as quickly as possible. Not to build something beautiful, polished, or complete.
Real-World Example: chian.io
Chian's "products" are often knowledge systems (Investment OS, Talk to Buffett) or content artifacts (podcast, newsletter). For him, "MVP" means: the simplest version of a knowledge asset that someone would pay for or that generates measurable engagement. Not necessarily software.
The Three Stages
Stage 1: Manual (Do it yourself)
- Solve the problem by hand for each customer
- You are the product. You are customer service, fulfillment, and engineering
- Write down every step you take — this becomes your process
- Example: Before Gumroad automated payouts, Sahil collected PayPal emails and sent payments manually, one by one
Stage 2: Processized (Systematize the manual work)
- Document your process on a piece of paper so anyone could do it
- If you go on vacation, someone else can take over
- You've built a system for working efficiently with each customer
- This is your "magic piece of paper"
Stage 3: Productized (Automate the process)
- Now automate each task so customers can use your product without you
- This is when you actually build software or a product
- Only build what you've already proven works manually
The Four Build Questions
Before building anything, answer:
- Can I ship it in a weekend? If not, reduce scope until you can.
- Is it making my customers' life a little better? That's the bar for MVP.
- Is a customer willing to pay for it? Be profitable from day one.
- Can I get feedback quickly? Build for people who can tell you if it's working.
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.
- 8d ago First seen · 102 lines · 75 tokens per session scan A 712ba31772d3
c31-mvp is a skill published in the GitHub repository ChianW/C31 (1 stars, last pushed 13d ago), licensed MIT. It adds 75 tokens to every session and 1,098 once invoked, about $0.0004 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 2026-08-31.
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7-section readiness scorecard for a LOCAL repo. Reports repo type + agent topology + MCP risk + test confidence + release readiness + recommended harness plan + scorecard. Exit 0 ready, 1 needs-work, 2 blocked. --json for the 6-field scorecard, --bundle for the ADR-031 schema-1 envelope.