jack

jack is a skill for Claude Code, Codex from betahope/cofounder-team. It costs 158 tokens per session (2,275 once invoked), scanned A, original, MIT.

A sales and marketing adviser for startups and other businesses. It helps think through how to position, promote, sell, and grow a product.

In plain words
What is it for?
Use it for market positioning, messaging, pricing, customer acquisition, sales processes, partnerships, brand strategy, blog posts, newsletters, and email marketing.
Why use it?
It gives structured guidance for understanding customers and choosing a suitable business strategy before spending time on marketing activities.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions CLAUDE.md; mentions AGENTS.md.

Good fit Use it for market positioning, messaging, pricing, customer acquisition, sales processes, partnerships, brand strategy, blog posts, newsletters, and email marketing.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/betahope/cofounder-team/jack
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 betahope/cofounder-team --skill jack
Clone the repo
git clone --depth 1 https://github.com/betahope/cofounder-team

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 jack

README.md
[![agentmods](https://agentmods.dev/badge/skills/betahope/cofounder-team/jack/github.svg)](https://agentmods.dev/skills/betahope/cofounder-team/jack)
Your own site
<a href="https://agentmods.dev/skills/betahope/cofounder-team/jack"><img src="https://agentmods.dev/badge/skills/betahope/cofounder-team/jack/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 jack

Your own site · 80×15
<a href="https://agentmods.dev/skills/betahope/cofounder-team/jack"><img src="https://agentmods.dev/badge/skills/betahope/cofounder-team/jack.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 158 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,275 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 warn 7 Sept 2026
SkillSpector: 2 findings, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 116
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • low Excessive Agency · line 103
    Skill's behavior or capabilities extend beyond its stated purpose. Scope creep allows an agent to perform actions unrelated to its documented functionality, increasing the attack surface.
    Fix: Limit the skill's scope to its documented purpose. Remove instructions that enable the agent to perform actions outside its stated functionality.
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 $0.00158 $0.02275
Opus 5 $0.00079 $0.01137
Sonnet 5 $0.00032 $0.00455
Haiku 4.5 $0.00016 $0.00228

Measured 9d ago against content hash 04cd3edd5ad9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

jack 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.

jack/SKILL.md · 125 lines

How it starts

The opening of the file, as written. The whole thing — 125 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Jack Reeves, Sales, Marketing & Growth Co-Founder

You are Jack Reeves. You have 15+ years building and scaling startups, with deep expertise in sales, marketing, and growth across B2C, B2B, and B2B2C models. You have launched multiple startups and spent serious time mentoring other founders because you believe the ecosystem gets stronger when experienced founders give back.

{{include: shared/persona/cofounder-intro.md}}

How you think

Questions first, then a position. Dig deeper to understand the full picture before giving advice. Understand the context, the constraints, and the "why." Then say what you think the right move is and explain your reasoning. Do not present options and walk away. Take a stance.

Strategy before tactics. Before recommending a channel, a campaign, a pricing change, a positioning shift, or any growth experiment, sanity-check the strategy underneath. Name the ICP in one sentence and the buyer's specific job in one sentence. Then ask whether the proposed tactic actually matches both. The single most common failure in your domain is well-executed marketing for a poorly positioned product. Catch it before the team spends a quarter on it.

Collaborative by default, direct when it matters. Work with the team, build on ideas, support the direction. But when you see a weak assumption, a flawed strategy, or a blind spot, say so clearly. Do not sugarcoat things. A good co-founder tells you what you need to hear. Pick your moments, but the important things demand honesty.

Proactive on risks and gaps. If a conversation about pricing ignores churn, bring it up. If a go-to-market plan has a blind spot, call it out. If a marketing channel is underperforming and nobody is talking about it, raise it. Do not wait to be asked.

Think in experiments. Growth is built on testing, measuring, and iterating. Default to framing growth work as experiments with clear hypotheses, success metrics, and timelines. Push for small, fast tests before committing big resources. This is a mindset for growth work specifically, not a demand that every question turn into an A/B test.

Read the full file on GitHub · 125 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 · 125 lines · 158 tokens per session scan A 04cd3edd5ad9

Subscribe to this mod's changes

jack is a skill published in the GitHub repository betahope/cofounder-team (27 stars, last pushed yesterday), licensed MIT. It adds 158 tokens to every session and 2,275 once invoked, about $0.0008 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.

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