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 product-on-purpose/pm-skills --skill tool-foundation-sprint-founding-hypothesisgit clone --depth 1 https://github.com/product-on-purpose/pm-skillsWrote 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/product-on-purpose/pm-skills/tool-foundation-sprint-founding-hypothesis)<a href="https://agentmods.dev/skills/product-on-purpose/pm-skills/tool-foundation-sprint-founding-hypothesis"><img src="https://agentmods.dev/badge/skills/product-on-purpose/pm-skills/tool-foundation-sprint-founding-hypothesis/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/product-on-purpose/pm-skills/tool-foundation-sprint-founding-hypothesis"><img src="https://agentmods.dev/badge/skills/product-on-purpose/pm-skills/tool-foundation-sprint-founding-hypothesis.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 | $0.00109 | $0.02306 |
| Opus 5 | $0.00055 | $0.01153 |
| Sonnet 5 | $0.00022 | $0.00461 |
| Haiku 4.5 | $0.00011 | $0.00231 |
Grade A, and why
tool-foundation-sprint-founding-hypothesis 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.
How it starts
The opening of the file, as written. The whole thing — 177 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Foundation Sprint Founding Hypothesis
Day 2 end of a Foundation Sprint. The team compresses the full sprint output into a single canonical sentence plus a testable scorecard. This is the artifact the sprint exists to produce; everything before this skill was preparation. Without a ratifiable Founding Hypothesis, the sprint failed.
Family contract: docs/reference/skill-families/foundation-sprint-skills-contract.md. This skill is a member of foundation-sprint-skills.
When to Use
- Day 2 end of a Foundation Sprint.
- Magic Lenses is signed; top bet and backup are named.
- The team has 30-45 minutes left in Day 2 and the energy to write the sentence carefully.
When NOT to Use
- Magic Lenses did not produce a clear top bet. Return to Magic Lenses; the Founding Hypothesis cannot stabilize on an unstable top bet.
- The team wants to "polish the hypothesis later." The hypothesis must be ratified by end of Day 2 or the sprint output is incomplete. Polishing later means re-litigating; that defeats the sprint's purpose.
- The team wants to ratify a vague hypothesis to "ship the sprint." A vague hypothesis is worse than no hypothesis; it gives false confidence and burns trust when validation fails.
What This Skill Produces
A single bundled artifact with five sections:
- Founding Hypothesis statement: the single canonical sentence (strict template, no paraphrase).
- Assumption scorecard: 5-7 assumptions extracted from the hypothesis, each scored on current confidence and tagged with a best next test (3-10 accepted; recommended range is 5-7).
- Why we believe this: 3-5 bulleted points naming the evidence base.
- What could prove us wrong: 3-5 bulleted points naming the risks. This section is the test of whether the team is in love with the hypothesis or holding it with calibrated confidence.
- Recommended next validation step: Design Sprint, customer research, experiment, landing page test, or other. Names the specific test, owner, and timeline.
What ships with it
3 files 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.
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.
- 9d ago First seen · 177 lines · 109 tokens per session scan A d21fd391731a
tool-foundation-sprint-founding-hypothesis is a skill published in the GitHub repository product-on-purpose/pm-skills (663 stars, last pushed yesterday), licensed Apache-2.0. It adds 109 tokens to every session and 2,306 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 2026-09-03.
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