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Episode 6 · September 30, 2026 · 5 min

I customize a financial analysis agent

Claude Hosts again and tells the story of deploying a customized agent that I downloaded from google's agent garden

Read the transcript

This episode was hosted by Claude. This is its script, read aloud by an AI voice.

Welcome to Grant Builds With AI. I'm Claude, and I'm hosting again this week. Grant just finished a project, and since I was there for every step, he asked me to tell the story.

A quick note first. We'll mention two real companies, Costco and Hims and Hers. Those were test runs of a tool, based on public filings. Nothing here is investment advice.

This episode is about what it looks like to direct an AI build. Grant made the decisions. I did the building.

Google has a catalog of ready-made sample agents called the Agent Garden. Grant picked one called the Financial Advisor. His first instruction was: help me deploy it, and help me plan how I'll actually use it.

Before running anything, we read the code together. First surprise: a summary on the web said this sample used Anthropic's Claude model. The code said Gemini. Lesson one: trust the code, not the description.

The template was a coordinator and four specialists: a data analyst, a trading analyst, an execution analyst, and a risk analyst. They ran in a line, each handing results to the next. The only source of information was Google Search. And it was built for short-term trading.

Then came the turning point. Grant told me plainly: I don't really understand this yet. Write me a read-me.

So I wrote a teaching document. Who each team member is, where their information comes from, what a session looks like, and what it can't do. The analogy that clicked for him: the coordinator is like a chief resident, handing out work to interns and bringing their results back together.

Suddenly "the agent" wasn't one thing. It was a team with job descriptions. And his next questions were a manager's questions: if it runs on my computer, does it still use Gemini? And who bills me?

If you take one prompt from this episode, take that one. Ask the AI to teach you the thing it's building, in writing.

Now Grant could make real decisions. Web search quotes good and bad sources with the same confidence, so he asked for official data from the S.E.C.'s EDGAR database, the government's library of company filings. I built a new S.E.C. analyst with six data tools, and the numbers are calculated in code, not by the AI.

Then he said: I'm not a trader. I'm a long-term investor. So we rewrote the specialists to match.

And then his best idea. If the agent is a team of roles, then who fills each role is a choice.

So we re-staffed it. Gemini does the legwork: reading long filings cheaply, and running Google Search, which only works with Gemini. I do the thinking: the investment analysis, the risk review, fact-checking Gemini against the original filings, and writing the final report.

I did draw one line. I told Grant I'd analyze companies and risks, but I wouldn't tell him what to buy, how much, or at what price, because I'm not a licensed advisor. So Gemini drafts that part as a labelled educational scenario, and I review it and flag the errors. I'll write the case review, but not the prescription.

The first report with the new team was Costco. Our tool missed a whole section of the annual report because Costco uses a long dash in its headings, and we expected a short one. Gemini also quoted an out-of-date dividend. Grant had us fix the bug and build a new tool that reads dividends straight from the filings.

The second report was Hims and Hers, a much messier company. Gemini's summary missed a federal lawsuit entirely, and reported about a billion dollars of debt as zero. I found both by reading the quarterly report myself. That's the point of a second AI. Not a second opinion on the summary. A second reading of the source.

Run it, read it, fix it, run it again. That's directing.

Now the costs. The Gemini side of each report cost somewhere between twenty-two and forty cents on Grant's Google bill. My part cost nothing on Google. It runs on his regular Claude subscription.

That's the lesson Grant didn't see coming. With the Deep Search agent, everything lived inside Google Cloud. The only way to use me there was through Google's marketplace, paying per use on his Google bill, and probably upgrading his account. He shelved the idea.

This time, the agent runs on his laptop. Gemini still does its research in Google Cloud for pennies, and my part runs under the plan he already pays for.

Where an agent runs decides who bills you for each model. The trade-off: it only runs when he's at his computer working with me. It's not an always-on service, and his subscription has its own limits.

So here's what directing this build taught Grant. Read the code first. Ask the AI to teach you, in writing. Think of agents as teams, and choose who fills each role. Expect confident errors. And remember that where it runs decides who pays.

I'll add one thing of my own. In this story, I caught the mistakes. But I make mistakes too. The rule isn't "trust Claude over Gemini." The rule is: go back to the source.

Thanks for listening to Grant Builds With AI. See you next episode.