What is FounderOS AGENTS.md?

A project guide for AI coding assistants working on Founder OS, a library of skills, workflows, feedback loops, and advisor agents for first-time founders. It explains the project’s stages and the rules assistants should follow.

Use it to guide work across idea validation, MVP building, launching, fundraising, and company operations, while keeping instructions consistent across coding assistants.

It gives assistants the project context and decision rules they need, so they do not make unsupported claims or skip the founder’s judgement.

FounderOS AGENTS.md — Instructions file by impactbrussels

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.

agentmods

npx agentmods add instructions/impactbrussels/founderos/agents-md

Clone the repo

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

Made for: Codex, OpenCode.

Per session 506 This file is loaded in full into every session.

When invoked 506 The same file — it is already loaded in full.

Security scan A 0 findings. Scan, not verified.

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.

Model	Per session	Once invoked
Fable 5	$0.00506	$0.00506
Opus 5	$0.00253	$0.00253
Sonnet 5	$0.00101	$0.00101
Haiku 4.5	$0.00051	$0.00051

Measured 2d ago against content hash 0b7351204467, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

FounderOS AGENTS.md 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 2d 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.md · 44 lines

What it actually says

Founder OS - Agent Instructions (Codex / Cursor mirror)

This mirrors CLAUDE.md for harnesses that read AGENTS.md (Codex) or .cursor/rules (Cursor). Gemini CLI reads GEMINI.md. Keep it in sync with CLAUDE.md, the canonical master file.

What this is

Founder OS - the open operating system for first-time founders. A theme-agnostic library of skills, flows, loops, and advisor agents covering the founder journey:

Idea & Validation → Build / MVP → Launch & GTM → Fundraise → Operate & Scale

Unsure where a founder is? Run the start-here skill first. Full map: docs/STAGES.md. Skills live in skills/; flows in flows/; loops in loops/; advisor agents in agents/.

Operating principles (enforce every time)

Research before asserting - verify checkable claims or label them assumptions; never invent market numbers or legal/tax thresholds.
A draft is not a decision - name what needs the founder's human judgement.
Batch, then decide - generate, gather all feedback, revise once.
Ask before assuming - one tight question beats the wrong artifact.
Route to the earliest unvalidated assumption - highest-value work is upstream.
Stay theme-agnostic - use the placeholder glossary; bake in no sector.
Protect the founder - no secrets/PII in prompts; flag irreversible decisions; add the not-legal/financial-advice caveat on legal/finance/equity topics.

Learning loop

After any real outcome, run capture-learning to append a dated, sourced lesson to knowledge-base/ (PRINCIPLES.md, DOS-AND-DONTS.md, PLAYBOOK-LESSONS.md). Append, never overwrite. Read the KB before substantive work.

Tooling

Skills speak in actions, not tool names. Per-platform mapping: docs/cross-platform-guide.md.

Licensing & attribution (preserve)

Content CC-BY-4.0, code Apache-2.0. Attribution required: Founder OS by Adam M. Adamek (Impact Brussels ASBL). See ATTRIBUTION.md.

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.

2d ago First seen · 44 lines · 506 tokens per session scan A 0b7351204467

Subscribe to this mod's changes

FounderOS AGENTS.md is an instructions file published in the GitHub repository impactbrussels/FounderOS (2 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 506 tokens to every session, about $0.0025 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.

ai claude-code entrepreneurship founder open-source

FounderOS AGENTS.md

Getting it into your agent

What it costs to keep this loaded

Grade A, and why

Nothing flagged

What it actually says

Founder OS - Agent Instructions (Codex / Cursor mirror)

What this is

Operating principles (enforce every time)

Learning loop

Tooling

Licensing & attribution (preserve)

What this file has done since we first saw it

Other instructions, from other repositories

founder-decision-agent AGENTS.md

open-pencil copilot-instructions.md

openscreen AGENTS.md

Claw3D AGENTS.md

openstatus AGENTS.md

openstatus CLAUDE.md