Notes · by David He

Notes fromproduction.

What I learn building and fixing production systems, written down as I go: AI agents, back-office automation, and what it takes to make an AI-built app safe to ship. Plain words, from the engineer who does the work.

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AI Implementation Strategies

A Week With a Personal AI Agent: It Sent the Email Without Asking, and Waited for My Click to Spend Money

A week of errands with Meta's Muse: it emailed support for me unasked, but spending money still took my click. Where to draw that line.

October 1, 20265 min read
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Cost Reduction Through Automation

Your AI Plan Got Smaller. Five Steps to Stop Depending on One Model

AI plans now buy less of the best models. Five steps I took to make my context and tools portable, so switching models does not mean starting over.

October 1, 20265 min read
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AI Implementation Strategies

Your old AI agent conversations are worth more to the next agent than to you

Most people never reopen an AI conversation. Six ways I put old agent transcripts to work, and the one rule to follow before trusting one.

September 30, 20264 min read
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AI Implementation Strategies

What I learned trying to use Jev to judge AI-generated photos

Jev can't see images, so its photo scores are only as good as the model describing each photo. What six describers taught me.

September 28, 20265 min read
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AI Implementation Strategies

What I changed in my AI workflows after trying Claude Opus 5.5

What changed when I audited my coding-agent skills with Opus 5.5: fewer procedural rules, clearer ownership, and stronger verification.

September 27, 20265 min read
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AI Implementation Strategies

How I Automated Myself Out of a Job (In a Good Way)

I built an AI webmaster so my client could stop waiting on me. Here's how it works, what broke, and what I'd do again.

September 26, 20267 min read
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AI Implementation Strategies

Why So Much AI Writing Sounds the Same, and What I Am Doing About Mine

A model can copy how I sound. It cannot decide what I think, which is why I'm spending more time writing, not less.

September 22, 20265 min read
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Cost Reduction Through Automation

An $80-a-Month Coding Tool Matched What I Was Paying $200 a Month For

An $80/month AI coding tool matched a $200/month subscription on one task, used a fraction of the tokens, and defaulted to better privacy. One gap: no ZDR.

September 19, 20265 min read
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AI Implementation Strategies

Why I Ordered a $10,000 Mac Studio for Local AI

A practical look at the rate limits, data constraints, and hardware tradeoffs behind one agency's move toward local AI.

September 18, 20264 min read
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AI Implementation Strategies

Why Nextdoor Suspended My AI Agent for Doing Exactly What I Approved

An AI agent got suspended for replying to job applicants too fast - a preview of what happens as agents become the majority of web traffic.

September 17, 20265 min read
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AI Implementation Strategies

Why We Checked an AI-Visibility Sales Pitch Instead of Ignoring It

A cold AI-visibility sales pitch got the symptom right and the fix wrong - and pointed straight at bugs we had shipped on our own site.

September 16, 20264 min read
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Economic Adaptation

The danger isn't that AI turns evil. It's that we're racing.

The people who understand AI best are the most scared of it. The danger is not evil AI, it is the arms race - and three rules I run every agent by.

September 16, 20265 min read
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AI Implementation Strategies

The scream test hears only what still points at it

Pruning 325 agent skills by waiting for errors missed the quiet failures; three counts from the logs found them.

September 15, 20264 min read
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Cost Reduction Through Automation

The error message is the most honest bill you will get for your AI tooling

A local model refused a two-letter prompt because my coding tool sent 1,500 skills first. Two ways to see what your AI tooling sends before you pay for it.

September 13, 20265 min read
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Economic Adaptation

Intelligence Is Now Cheap. The Signature Is Not.

AI made first drafts cost a few dollars. What businesses still pay for is the person who checks the draft and signs it. How to find that gap in your own costs.

September 12, 20265 min read
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AI Implementation Strategies

Fable 5.1 and GPT Astra Changed How I Prompt. The Effort Dial Was the Wrong Place to Reach First.

Cranking effort to max burns a week of tokens in a night. Sort the task first: walk-away or sit-at-the-desk, then pick the model.

September 11, 20264 min read
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Economic Adaptation

Check Whether You Are Allowed to Use Your AI Tools Before You Build on Them

A compliance contract left exactly two legal ways to use AI on client data. Checking which tools qualified turned into a lesson about vendor dependency.

September 11, 20266 min read
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AI Implementation Strategies

By Hand or By AI Is the Wrong Question

A designer with twenty years of depth quit AI because the output looked like a template. He was right about the output, wrong about the conclusion.

September 8, 20263 min read
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Economic Adaptation

AI Is Not Erasing Careers. It Is Erasing the Bottom Rung.

Whole careers are not disappearing. The entry-level work that turned graduates into trusted professionals is, and nobody has replaced it.

September 5, 20263 min read
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AI Implementation Strategies

What Claude's Text Watermark Actually Does, and What It Cannot Do

Crawlers cannot read Claude's text watermark, and retyping does not remove it. What it is, who can read it, and why it changes nothing.

September 2, 20263 min read
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Integration Best Practices

Built-In AI or an Outside Tool? Start Inside, Almost Always

The AI built into software you already pay for is usually worse. Start with it anyway, because every integration is one more thing that breaks.

August 30, 20263 min read
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AI Implementation Strategies

The One-Page AI Policy Your Business Actually Needs

An AI policy written by AI gives you four pages of principles and changes nothing. The version that works fits on one page.

August 29, 20263 min read
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AI Implementation Strategies

Stop Waiting for the Green Light. Build the Alarm Instead.

Nobody is coming to say AI is allowed. What owners actually want is to find out their automation broke before a customer does.

August 28, 20263 min read
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Economic Adaptation

Who Wrote the Task? A Cheap Test for Any Agentic AI Product

Before you sign anything with the word agentic on it, ask who decided the task needed doing. Usually the answer is a person.

August 27, 20263 min read
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Integration Best Practices

A Gateway Abstracts Your Bill, Not Your Integration

Swapping AI models looks like one config line. A gateway abstracts your bill, not your integration, and the difference cost me a day.

August 26, 20263 min read
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AI Implementation Strategies

Where to Start With AI: Automate the Job You Would Rather Not Do

Where to begin with AI: pick the task you avoid but still have to do well. What building a voice agent to screen candidates taught me.

August 24, 20263 min read
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AI Implementation Strategies

Fable 5 Is the Real Thing, and You Have Until July 7 to Test It Cheaply

Fable 5 is a genuine step change, not hype. Why early adopters compound their advantage, and how to test it on Claude Max before the July 7 window closes.

July 4, 20268 min read
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AI Implementation Strategies

The Agent Spend Playbook: 5 Rules to Set Before You Let AI Agents Run

Autonomous AI agents are cheap when they replace coordination and expensive when they replace thinking. Five rules — with real numbers — that decide which one you get.

July 3, 20267 min read
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Hit one of these in your own system?

Bring the app or the process to a free 15-minute call. I will tell you what I would look at first, and whether I am the right person for it.