Lenny Skills is a collection of product-management and engineering workflows for Claude Code and other AI agents, covering areas such as strategy, research, planning, shipping, growth, and hiring. Each skill gives an agent specialized guidance, frameworks, checklists, or templates for product work, and the catalogue contains many of these skills.
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 RefoundAI/lenny-skills --skill evaluating-trade-offsgit clone --depth 1 https://github.com/RefoundAI/lenny-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/refoundai/lenny-skills/evaluating-trade-offs)<a href="https://agentmods.dev/skills/refoundai/lenny-skills/evaluating-trade-offs"><img src="https://agentmods.dev/badge/skills/refoundai/lenny-skills/evaluating-trade-offs/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/refoundai/lenny-skills/evaluating-trade-offs"><img src="https://agentmods.dev/badge/skills/refoundai/lenny-skills/evaluating-trade-offs.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 | $0.00043 | $0.01283 |
| Opus 5 | $0.00022 | $0.00642 |
| Sonnet 5 | $0.00009 | $0.00257 |
| Haiku 4.5 | $0.00004 | $0.00128 |
Grade A, and why
evaluating-trade-offs 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 12d 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 — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Evaluating Trade-Offs
Master the art of weighing competing options to maximize long-term impact and team velocity.
Help the user with evaluating trade-offs using insights from 14 guests and posts across Lenny's Podcast and Newsletter.
How to Help
- Framework Selection - Match the right decision template to the specific tradeoff scenario you are facing.
- ROI Calculation - Assist in modeling the long-term business impact versus the operational costs of a proposed path.
- Stakeholder Communication - Refine how you present tradeoffs to leadership to ensure they see the hidden costs of saying yes.
- Bias Detection - Identify common traps like the sunk cost fallacy or the just one more engineer myth in your current thinking.
Core Principles
Surface rabbit holes during shaping
Ryan Singer: "I often use this analogy of if you're doing a home renovation, you can have the most beautiful rendering of the new bedroom and we're going to have these lamps on the side of the bed that are coming out from the wall. But if you haven't checked if there's electricity in that wall there or not, it's going to drastically change the cost and the time and everything."
Involve senior engineers early to identify technical complexities and infrastructure constraints before committing the team to a high-fidelity design.
Quantify the risk of inaction
From "This Week #13: Balancing outcome-thinking with design and technical requirements ⚖️": "To answer your question about how we balanced this outcome-thinking with engineering and design needs (which often don’t directly drive that outcome), it’s simple — extend your outcome thinking further out into the future. How much would this work benefit your outcome (e.g. growth, quality, retention) 1+ years out? What happens if you don’t do it? What are the chances of it being successful?"
Evaluate major technical or design investments by comparing the impact of doing the work now versus the cost and risk of doing nothing.
What ships with it
2 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.
- 12d ago First seen · 77 lines · 43 tokens per session scan A 214330cd9ace
evaluating-trade-offs is a skill published in the GitHub repository RefoundAI/lenny-skills (1,318 stars, last pushed 1mo ago), licensed MIT. It adds 43 tokens to every session and 1,283 once invoked, about $0.0002 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.
Other skills, from other repositories
llama-cpp
Run LLM inference with llama.cpp on CPU, Apple Silicon, AMD/Intel GPUs, or NVIDIA — plus GGUF model conversion and quantization (2–8 bit with K-quants and imatrix). Covers CLI, Python bindings, OpenAI-compatible server, and Ollama/LM Studio integration. Use for edge deployment, M1/M2/M3/M4 Macs, CUDA-less…
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior. 4-phase root cause investigation — NO fixes without understanding the problem first.
github-auth
Set up GitHub authentication for the agent using git (universally available) or the gh CLI. Covers HTTPS tokens, SSH keys, credential helpers, and gh auth — with a detection flow to pick the right method automatically.
ideation
Generate project ideas through creative constraints. Use when the user says 'I want to build something', 'give me a project idea', 'I'm bored', 'what should I make', 'inspire me', or any variant of 'I have tools but no direction'. Works for code, art, hardware, writing, tools, and anything that can be made.
notion
Notion API for creating and managing pages, databases, and blocks via curl. Search, create, update, and query Notion workspaces directly from the terminal.
ocr-and-documents
Extract text from PDFs and scanned documents. Use webextract for remote URLs, pymupdf for local text-based PDFs, marker-pdf for OCR/scanned docs. For DOCX use python-docx, for PPTX see the powerpoint skill.