product-lens

product-lens is a skill for Claude Code, Codex from JunMystery/Agent-Guidance-Python. It costs 33 tokens per session (727 once invoked), scanned A, a copy of product-lens, MIT.

A product-planning guide that tests whether an idea solves a real problem before engineering work begins.

In plain words
What is it for?
Use it to investigate product ideas, define the target user and problem, choose an MVP, and decide whether a feature is worth building.
Why use it?
It helps avoid building features without a clear user, need, success measure, or smallest useful version.

Skill for Claude CodeCodex

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 skills/junmystery/agent-guidance-python/product-lens
Any agent
npx skills add JunMystery/Agent-Guidance-Python --skill product-lens
Clone the repo
git clone --depth 1 https://github.com/JunMystery/Agent-Guidance-Python

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 product-lens

README.md
[![agentmods](https://agentmods.dev/badge/skills/junmystery/agent-guidance-python/product-lens.svg)](https://agentmods.dev/skills/junmystery/agent-guidance-python/product-lens)
Your own site
<a href="https://agentmods.dev/skills/junmystery/agent-guidance-python/product-lens"><img src="https://agentmods.dev/badge/skills/junmystery/agent-guidance-python/product-lens.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 727 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00033 $0.00727
Opus 5 $0.00016 $0.00364
Sonnet 5 $0.00007 $0.00145
Haiku 4.5 $0.00003 $0.00073

Measured yesterday against content hash 8eaea4af3b14, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

product-lens 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 yesterday.

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.

Origin

This is a copy

100% identical to product-lens — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/product-lens/SKILL.md · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Product Lens — Think Before You Build

This lane owns product diagnosis, not implementation-ready specification writing.

If the user needs a durable PRD-to-SRS or capability-contract artifact, hand off to product-capability.

When to Use

  • Before starting any feature — validate the "why"
  • Weekly product review — are we building the right thing?
  • When stuck choosing between features
  • Before a launch — sanity check the user journey
  • When converting a vague idea into a product brief before engineering planning starts

How It Works

Mode 1: Product Diagnostic

Like YC office hours but automated. Asks the hard questions:

1. Who is this for? (specific person, not "developers")
2. What's the pain? (quantify: how often, how bad, what do they do today?)
3. Why now? (what changed that makes this possible/necessary?)
4. What's the 10-star version? (if money/time were unlimited)
5. What's the MVP? (smallest thing that proves the thesis)
6. What's the anti-goal? (what are you explicitly NOT building?)
7. How do you know it's working? (metric, not vibes)

Output: a PRODUCT-BRIEF.md with answers, risks, and a go/no-go recommendation.

If the result is "yes, build this," the next lane is product-capability, not more founder-theater.

Mode 2: Founder Review

Reviews your current project through a founder lens:

1. Read README, CLAUDE.md, package.json, recent commits
2. Infer: what is this trying to be?
3. Score: product-market fit signals (0-10)
   - Usage growth trajectory
   - Retention indicators (repeat contributors, return users)
   - Revenue signals (pricing page, billing code, Stripe integration)
   - Competitive moat (what's hard to copy?)
4. Identify: the one thing that would 10x this
5. Flag: things you're building that don't matter

Mode 3: User Journey Audit

Maps the actual user experience:

1. Clone/install the product as a new user
2. Document every friction point (confusing steps, errors, missing docs)
3. Time each step
4. Compare to competitor onboarding
5. Score: time-to-value (how long until the user gets their first win?)
6. Recommend: top 3 fixes for onboarding

Read the full file on GitHub · 93 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. yesterday First seen · 93 lines · 33 tokens per session scan A 8eaea4af3b14

Subscribe to this mod's changes

product-lens is a skill published in the GitHub repository JunMystery/Agent-Guidance-Python (2 stars, last pushed 1mo ago), licensed MIT. It adds 33 tokens to every session and 727 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to product-lens, differing in 0 lines, and is treated as a copy.

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