Inside Anjin #24: The Anatomy of a Useful Agent

Last time, we shared the story of a failed agent. This time, we’re showing one that worked — and what made the difference. Here’s how a few key design decisions turned a generic concept into a trusted daily tool.
What makes an AI agent stick? Learn how one Anjin agent became essential — and the UX patterns we’re now applying to every build.
Useful agents don’t shout. They solve.

We’ve tested dozens of agents internally. Some had clever logic. Some had slick interfaces. But only a few crossed the line into habit — becoming tools we kept reaching for without thinking.

This is one of them. And this is what made it work.

The Agent: Snippet to Summary

We built this one to help us convert small blocks of copy — internal notes, meeting takeaways, email fragments — into short, structured summaries that could be reused across different formats.

Its goal was to:

  • Take 1–3 messy paragraphs
  • Identify the point, not just the topic
  • Structure the insight in a few clear lines
  • Optionally suggest a headline or CTA

It became something we used almost every day.
Here’s why.

What Made It Work

After testing, refining, and rebuilding it twice, a few patterns emerged:

1. It had a clear input expectation

The agent gave simple, visual guidance: “Paste up to 3 paragraphs of rough text.”
Nothing more. That constraint helped users trust the outcome.

2. The output was structured and human

It returned:

  • A single-line summary
  • A 2–3 sentence expansion
  • A suggested use case or next step

This made it immediately usable in content, posts, or team docs — without editing.

3. It saved real time

Instead of rephrasing or rewriting manually, the agent gave us a solid first draft in seconds. The best part? It felt like us, just cleaned up.

4. It didn’t try to be too smart

No brand tone sliders. No dropdowns. Just good defaults and safe assumptions.
That made it faster — and more reliable — than tools with endless config options.

What It Taught Us About Good Agent Design

From this (and a few other “sticky” agents), we pulled a few principles we now use across the board:

  • Useful > impressive
    An agent doesn’t need to wow you. It needs to work.
  • Constraints create trust
    When inputs are too flexible, outputs become unpredictable. Good agents are clear about what they need.
  • Output format matters
    If a user still has to reformat the result, they won’t use it again.
  • Defaults are design
    Well-chosen defaults can remove the need for 80 percent of interaction. That’s a win.

Why This Matters Ahead of Launch

We’re not aiming for a catalogue of shiny agent demos.
We’re aiming for a set of agents that feel like part of your workflow — not a layer on top of it.

When Anjin launches in September, the agents you’ll see first will be the ones that earned their place.
This one is on that list.

Final Thought: When It’s Useful, You Don’t Need to Sell It

The agents that stick are the ones that quietly earn a slot in your day.
They don’t need fanfare. They just need to work.

This is the bar we’re setting.
And every agent we release is designed to clear it.

Want to build or use agents like this when Anjin opens?
Join the community for early access and insights into what we’re launching first.

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