fundamental-analysis

fundamental-analysis is a skill for Claude Code from yennanliu/InvestSkill. It costs 9 tokens per session (892 once invoked), scanned A, original, MIT.

A guide to analyzing US stocks from their financial statements, which report a company’s revenue, profits, assets, debts, and cash flows.

In plain words
What is it for?
Use stock-eval instead for the covered fundamental, quality, and valuation analysis. The guide itself mainly documents measures such as P/E, P/B, P/S, EV/EBITDA, ROE, and ROIC.
Why use it?
It explains common financial ratios and valuation measures, but the guide says this analysis has been merged into the stock-eval skill.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the us-stock-analysis plugin — 27 skills shipped together

Good fit Use stock-eval instead for the covered fundamental, quality, and valuation analysis. The guide itself mainly documents measures such as P/E, P/B, P/S, EV/EBITDA, ROE, and ROIC.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/yennanliu/investskill/fundamental-analysis
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 yennanliu/InvestSkill --skill fundamental-analysis
Clone the repo
git clone --depth 1 https://github.com/yennanliu/InvestSkill

Made for: Claude Code.

Or install us-stock-analysis, the plugin that ships this one along with the rest of its 27 skills.

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 fundamental-analysis

README.md
[![agentmods](https://agentmods.dev/badge/skills/yennanliu/investskill/fundamental-analysis.svg)](https://agentmods.dev/skills/yennanliu/investskill/fundamental-analysis)
Your own site
<a href="https://agentmods.dev/skills/yennanliu/investskill/fundamental-analysis"><img src="https://agentmods.dev/badge/skills/yennanliu/investskill/fundamental-analysis.svg" alt="Measured on agentmods" height="20"></a>
Per session 9 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 892 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found 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 $0.00009 $0.00892
Opus 5 $0.00005 $0.00446
Sonnet 5 $0.00002 $0.00178
Haiku 4.5 $0.00001 $0.00089

Measured 8d ago against content hash 7f51cea843bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

fundamental-analysis 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.

plugins/us-stock-analysis/skills/fundamental-analysis/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fundamental Analysis

This skill has been merged into stock-eval. Use /us-stock-analysis:stock-eval for comprehensive fundamental + quality + valuation analysis.

Quick Reference — Key Ratios

Ratio Formula What It Measures
P/E (Price-to-Earnings) Market Price / EPS How much investors pay per dollar of earnings; compare to peers and history
P/B (Price-to-Book) Market Price / Book Value per Share Premium over net asset value; useful for financials and asset-heavy businesses
P/S (Price-to-Sales) Market Cap / Revenue Valuation relative to revenue; useful when earnings are negative or depressed
EV/EBITDA Enterprise Value / EBITDA Capital-structure-neutral earnings multiple; standard M&A and cross-sector benchmark
ROE (Return on Equity) Net Income / Shareholders' Equity Profitability relative to equity book value; decompose with DuPont for quality assessment
ROIC (Return on Invested Capital) NOPAT / Invested Capital True economic return on all capital deployed; compare to WACC to assess value creation
Current Ratio Current Assets / Current Liabilities Short-term liquidity; >1.5x generally healthy; <1.0x signals potential liquidity stress
D/E (Debt-to-Equity) Total Debt / Shareholders' Equity Financial leverage; higher ratio = more risk but also more return amplification

For the full analysis framework — income statement line-item breakdown, working capital cycle, DuPont decomposition, cash conversion cycle, Porter's Five Forces, Piotroski F-Score, DCF, ROIC/WACC, and risk matrix — use /us-stock-analysis:stock-eval.


Standard Signal Output

All analysis concludes with this standardized block:

## Thesis Invalidation

After delivering the analysis signal, specify what would reverse it:

**If signal is BULLISH — thesis breaks if:**
- Price closes below the MA200 / key support level identified in this analysis on above-average volume
- revenue growth decelerates below 5% for 2 consecutive quarters AND gross margin contracts >200bps
- Macro regime shift: Fed pivots hawkish unexpectedly, recession probability >60%

**If signal is BEARISH — thesis breaks if:**
- Price closes above key resistance / MA200 level with volume confirmation
- revenue reaccelerates >15% AND margin expansion resumes
- Fundamental improvement: surprise earnings beat >20% with guidance raise

**Re-run this analysis when:**
- [ ] Next earnings release
- [ ] Price moves ±15% from current level
- [ ] 60 days have elapsed
- [ ] Material news event (acquisition, leadership change, regulatory decision)

╔══════════════════════════════════════════════╗
║              INVESTMENT SIGNAL               ║
╠══════════════════════════════════════════════╣
║ Signal:      BULLISH / NEUTRAL / BEARISH     ║
║ Confidence:  HIGH / MEDIUM / LOW             ║
║ Horizon:     SHORT / MEDIUM / LONG-TERM      ║
║ Score:       X.X / 10                        ║
╠══════════════════════════════════════════════╣
║ Action:      BUY / HOLD / SELL               ║
║ Conviction:  STRONG / MODERATE / WEAK        ║
╚══════════════════════════════════════════════╝

Read the full file on GitHub · 67 lines

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. 8d ago First seen · 67 lines · 9 tokens per session scan A 7f51cea843bd

Subscribe to this mod's changes

fundamental-analysis is a skill published in the GitHub repository yennanliu/InvestSkill (204 stars, last pushed yesterday), licensed MIT. It adds 9 tokens to every session and 892 once invoked, about $0.0000 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.