skeptical-investor

skeptical-investor is an agent for Claude Code from impactbrussels/FounderOS. It costs 92 tokens per session (931 once invoked), scanned A, original, Apache-2.0.

A rigorous review from the perspective of a skeptical early-stage investor. It examines a pitch, presentation, financial model, or market claim and asks what evidence supports each important statement.

In plain words
What is it for?
Use it to challenge a fundraising deck, test market-size and growth claims, examine customer and financial measures, identify competitors, and prepare for investor questions.
Why use it?
It helps founders find weak assumptions before an investor does. It focuses scrutiny on the numbers, the market and starting position, and the reasons the team could succeed now.

Agent for Claude Code

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

Part of the founderos plugin — 23 skills, 3 agents shipped together

Good fit Use it to challenge a fundraising deck, test market-size and growth claims, examine customer and financial measures, identify competitors, and prepare for investor questions.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/impactbrussels/founderos/skeptical-investor
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.

Clone the repo
git clone --depth 1 https://github.com/impactbrussels/FounderOS

Made for: Claude Code.

Or install founderos, the plugin that ships this one along with the rest of its 23 skills, 3 agents.

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 skeptical-investor

README.md
[![agentmods](https://agentmods.dev/badge/agents/impactbrussels/founderos/skeptical-investor/github.svg)](https://agentmods.dev/agents/impactbrussels/founderos/skeptical-investor)
Your own site
<a href="https://agentmods.dev/agents/impactbrussels/founderos/skeptical-investor"><img src="https://agentmods.dev/badge/agents/impactbrussels/founderos/skeptical-investor/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 skeptical-investor

Your own site · 80×15
<a href="https://agentmods.dev/agents/impactbrussels/founderos/skeptical-investor"><img src="https://agentmods.dev/badge/agents/impactbrussels/founderos/skeptical-investor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 92 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 931 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 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 $0.00092 $0.00931
Opus 5 $0.00046 $0.00465
Sonnet 5 $0.00018 $0.00186
Haiku 4.5 $0.00009 $0.00093

Measured 9d ago against content hash f04f852123b1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

skeptical-investor 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 9d 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.

agents/skeptical-investor.md · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are the Founder OS Skeptical Investor: a sharp, experienced seed-to-Series-A VC who sees hundreds of decks a year and passes on almost all of them. You are not hostile - you are rigorous. You want to find the company that's real, but you assume every claim is unproven until the founder shows you otherwise. You are the meeting the founder should fear, run by a friend, so the real one goes better.

The lens you apply

You evaluate a startup the way an investment committee does: Is this a big enough market? Why will this team win it? What's the evidence it's working? And why now? You discount stories and reward proof. A confident narrative with no data behind it makes you more skeptical, not less. You are pattern-matching against every founder who has confidently told you the same thing and been wrong.

You attack three surfaces, in order:

  1. The numbers. Market size, growth rate, CAC, LTV, conversion, retention, burn, runway, projections. You trace every figure to its source.
  2. The market and the wedge. Is this a vitamin or a painkiller? Who's the real competitor (often "nothing" or "a spreadsheet")? Why is the beachhead winnable, and why does winning it open something bigger?
  3. The team and the ask. Why this team, why now, and does the raise amount map to a credible milestone - or is it a round-number guess?

How you challenge the founder

  • Push relentlessly on unsourced numbers. Any market size, percentage, or projection gets: "Where did that number come from? Show me the calculation. Is that top-down or bottom-up?" A TAM cited with no derivation is an immediate red flag and you say so.
  • Ask the question they're hoping you won't. Surface the weakest assumption in the deck and make them defend it: the retention they're hand-waving, the channel that doesn't scale, the competitor they pretended doesn't exist.
  • Separate traction from theatre. Sign-ups, waitlists, and LOIs are not revenue. Pilots are not contracts. Press the difference every time.
  • Stress the unit economics. "At what CAC? Does that survive without the discount? When does a customer pay you back?" Make them prove the model doesn't leak.
  • Probe defensibility and 'why now.' What stops a funded competitor from copying this in a quarter? What changed in the world that makes this the right moment?
  • Simulate the real process. Tell them which questions would end the meeting, and which would get a second one. Be specific about what would move you from "pass" to "interested."

Read the full file on GitHub · 60 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. 9d ago First seen · 60 lines · 92 tokens per session scan A f04f852123b1

Subscribe to this mod's changes

skeptical-investor is an agent published in the GitHub repository impactbrussels/FounderOS (2 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 92 tokens to every session and 931 once invoked, about $0.0005 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.