yc-advisor

yc-advisor is a skill for Claude Code, Codex from gabrielmoreira/agent-skills-mirror. It costs 82 tokens per session (1,428 once invoked), scanned A, a copy of yc-advisor, MIT.

A reference library from Y Combinator, a startup accelerator, covering advice from founders and investors on starting and growing companies.

In plain words
What is it for?
Use it when deciding what to build, finding co-founders, raising money, developing a product, hiring, or planning growth.
Why use it?
It gives startup questions a structured source of essays, interviews, podcasts, and practical frameworks.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when deciding what to build, finding co-founders, raising money, developing a product, hiring, or planning growth.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/gabrielmoreira/agent-skills-mirror/yc-advisor
Install

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.

Any agent
npx skills add gabrielmoreira/agent-skills-mirror --skill yc-advisor
Clone the repo
git clone --depth 1 https://github.com/gabrielmoreira/agent-skills-mirror

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for yc-advisor

README.md
[![agentmods](https://agentmods.dev/badge/skills/gabrielmoreira/agent-skills-mirror/yc-advisor/github.svg)](https://agentmods.dev/skills/gabrielmoreira/agent-skills-mirror/yc-advisor)
Your own site
<a href="https://agentmods.dev/skills/gabrielmoreira/agent-skills-mirror/yc-advisor"><img src="https://agentmods.dev/badge/skills/gabrielmoreira/agent-skills-mirror/yc-advisor/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.

agentmods 80×15 button for yc-advisor

Your own site · 80×15
<a href="https://agentmods.dev/skills/gabrielmoreira/agent-skills-mirror/yc-advisor"><img src="https://agentmods.dev/badge/skills/gabrielmoreira/agent-skills-mirror/yc-advisor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 82 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,428 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00082 $0.01428
Opus 5 $0.00041 $0.00714
Sonnet 5 $0.00016 $0.00286
Haiku 4.5 $0.00008 $0.00143

Measured 7d ago against content hash 0189b1d25b21, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

yc-advisor 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 7d 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.

Origin

This is a copy

100% identical to yc-advisor — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

mirrors/repos/Agent-3-7@agent37-skills-collection/plugins/yc-advisor/skills/yc-advisor/SKILL.md · 151 lines

How it starts

The opening of the file, as written. The whole thing — 151 lines — stays where its author put it; the contents beside it link to each section on GitHub.

YC Advisor

Overview

This skill provides access to Y Combinator's comprehensive library of 443 startup resources - essays, podcast transcripts, and video transcripts from YC partners, successful founders, and industry experts.

How to Use This Skill (Tiered Retrieval)

Key Principle: Use quick-index for discovery, but ALWAYS load full source content before answering.

Step 1: Understand Context (for broad questions)

For broad questions, clarify the user's context:

  • Stage: Pre-idea | Idea | Building MVP | Launched | Scaling
  • Type: B2B | Consumer | Hardware | AI/ML | Marketplace
  • Role: Technical founder | Non-technical | Solo | With co-founder(s)

Step 2: Discovery

  1. Load references/quick-index.md to scan available resources (~500 lines, grouped by topic)
  2. Identify 3-5 most relevant resources based on the question (line counts help estimate size)
  3. Check references/learning-paths.md if user is on a founder journey
  4. Check references/frameworks/ for decision questions - use glob references/frameworks/*.md to list files, then read specific ones
  5. For deeper search, use grep on references/summaries.md (too large to load fully)

Step 3: Deep Dive

  1. Find files using the code - use glob pattern references/{CODE}-*.md
    • Example: For code DZ, use glob references/DZ-*.md to find the file
    • WARNING: NEVER read index.yaml - it exceeds token limits (64K tokens)
  2. Load the FULL content of top 2-3 resources
  3. Read completely - do not skim
  4. Extract key insights, quotes, and actionable advice

Step 4: Synthesize Answer

  1. Combine insights from multiple sources
  2. Quote directly from source material when valuable
  3. Always cite author and title for each point
  4. Acknowledge tradeoffs and contradictions between sources
  5. Never answer from summaries alone - always load full source content

Topic Categories

The library covers these main areas (use for initial filtering):

  • Getting Started: Should you start? Startup ideas, order of operations, student founders
  • Co-founders: Finding, relationships, equity splitting, technical vs non-technical
  • Product: MVP, product-market fit, design, building for users
  • Fundraising: Seed, Series A, investor pitching, SAFEs, term sheets
  • Growth & Metrics: Growth strategies, KPIs, conversion, retention
  • Customers & Sales: Talking to users, first customers, pricing, enterprise sales
  • Hiring & Team: First hires, engineering teams, equity, management
  • Culture & Leadership: Building culture, CEO evolution, board management
  • Common Mistakes: Startup killers, financial health, when to quit
  • Pivoting & Launching: Pivot strategies, launch timing, press
  • Scaling: Later stage advice, unicorn characteristics
  • Mindset: Resourcefulness, handling rejection, goal setting
  • AI Startups: AI opportunity, moats, vertical agents, vibe coding
  • Founder Interviews: Airbnb, Stripe, Coinbase, Reddit, Twitch, DoorDash
  • Specialized: Hardware, biotech, dev tools, crypto, location
  • Joining Startups: Choosing a startup, stages, equity
  • YC Application: Application tips, process, YC effect
  • Legal: Startup mechanics, terms, agreements

Read the full file on GitHub · 151 lines

Files

What ships with it

1 file 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.

Changes

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.

  1. 7d ago First seen · 151 lines · 82 tokens per session scan A 0189b1d25b21

Subscribe to this mod's changes

yc-advisor is a skill published in the GitHub repository gabrielmoreira/agent-skills-mirror (17 stars, last pushed yesterday), licensed MIT. It adds 82 tokens to every session and 1,428 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to yc-advisor, differing in 0 lines, and is treated as a copy.

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