Verifier Loop and Evals for Chart Quality

> I almost don’t read code now. My approach with Roborev is it’s like my code reader. The mantra is: Roborev reads every line of code that is generated. It gets read multiple times. And so, whenever I push up a pull request, the branch gets re-reviewed. And so by the time I’m merging a pull request into a repository, the code has all been read by agents four or five times minimum. I look at the code in terms of structural detail: does it look right?

— Wes McKinney (creator of pandas, POSIT)

Wes, Jeremiah Lowin (Prefect), and Randy Olson (Good Eye Labs) join Hugo and his cohost Thomas Wiecki (PyMC Labs) for the premiere of Show Us Your Agent Skills, a live session where guests walk us through the exact skills, workflows, and setups they use to work with agents every day.

We Discuss:

* Wes McKinney on why he barely writes, or even reads, code anymore, his “software factory” of parallel agents, and RoboRev, the background reviewer that reads every line four or five times before he merges;

* The shift from “vibe coding” to agentic engineering, and why verification, not reading, is the part that actually matters;

* Jeremiah Lowin on years of context engineering: trickling voice memos, recorded meetings, and morning briefs into his agent’s memory substrate as a true “second brain”;

* Why Jeremiah picked OpenCode specifically for how deeply he can customize its memory, and what he’s building with FastMCP, Prefab, and Cardboard;

* Randy Olson on encoding human judgment, like Tufte’s rules for data visualization, directly into agent skills, so the agents themselves perform the verification;

* The “digital twin” Randy loads into his agents as a thought partner that pushes back instead of agreeing;

* Skills as thin drivers, progressive disclosure, and managing context rot across extended sessions;

* The rise of ephemeral, “just for me” software that agents finally make viable.

Skills and workflows discussed and shown in the episode:

* Wes’s RoboRev background code reviewer, his “software factory” dashboard, and his agentic engineering setup built on the Superpowers skills framework;

* Jeremiah’s “explain” skill (which anchors every other skill he has), his voice memo memory pipeline, his FastMCP and Prefab projects, and Cardboard, his ephemeral presentation tool;

* Randy’s data visualization verifier skills, his digital twin thought partner prompt, his cron job reports for colleagues, and his reflect and improve skill design pattern.

Check out the GitHub repo where we’re starting to drop some of these skills and workflows for you to grab and try yourself.

You can also find the full episode on Spotify, Apple Podcasts, and YouTube.

You can also interact directly with the transcript here in NotebookLM: If you do so, let us know anything you find in the comments!

Up next on Show Us Your Agent Skills: Hilary Mason (CEO, HiddenDoor), Bryan Bischof (Theory Ventures), Eric Ma (Research DS lead, Moderna Therapeutics), and Tomasz Tunguz (Theory Ventures). Register on lu.ma to join live, or catch the recording afterwards.

👉 Want to learn how to apply agentic engineering to the world of data science? Come build the future of Agentic Data Science with us in our upcoming course. It’s a live cohort with hands on exercises, capstones, and reusable agent skills, OSS code, and notebooks that will 10x your data science projects. Sign up here.👈

LINKS

* spicytakes.org, Wes McKinney’s website

* RoboRev, Wes’s background code reviewer

* Agents View, Wes’s agent session database

* Middleman, Wes’s local GitHub dashboard

* Superpowers, Jesse Vincent’s skills framework that Wes builds on

* An Open Source Maintainer’s Guide to Saying No, by Jeremiah Lowin

* FastMCP

* Prefab, Jeremiah’s Python DSL for generative UIs

* Beautiful Charts with AI, by Randy Olson

* The Coding Agent is Dead, by Amp

* Building Effective Agents, by the Anthropic team

* Show Us Your Agent Skills, the GitHub repo where we are dropping skills and workflows from the show

* Upcoming Events on Luma

* Vanishing Gradients on YouTube

* Watch the podcast video on YouTube

* Come build the future of Agentic Data Science with us in our upcoming course.

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