Agents are LLMs with tool-use. They don’t just respond to you, they can go and do things for you. But what does ‘tool-use’ actually mean? What tools?

The most common tools are in the form of CLI. Agents communicate in text, CLIs are text in/text out, so it’s a natural fit. A CLI is a text-based way to control software. You type a command, something happens.

Here’s a simple example - organising files, using the bash tool.

"Rename all 400 product photos to match our SKU format, resize them to 1200x1200, and sort them into folders by category."

First the agent lists files to understand what it’s working with.

COMMAND:
ls ./product-photos/

OUTPUT:
file_1.jpg
file_2.jpg
file_3.jpg ... (400 files)

• ’ls’ is the command for ‘list’

• ./product-photos/ is where the files are located

Then creates the folder structure

COMMAND:
mkdir -p ./output/{shoes,bags,jackets,hats}

OUPUT:
output/
├── shoes/
├── bags/
├── jackets/
└── hats/

• ‘mkdir’ is the command for ‘make directory’ (directory is a folder), here it’s creating 5 - output, output/shoes, output/bags, output/jackets, output/hats

• flags modify what a command does: -p here means ‘create any missing parent folders too.’ So if ./output/ doesn’t exist yet, it’ll make that too

Then resizes the images

COMMAND:
mogrify -resize 1200x1200 ./product-photos/*.jpg

OUTPUT:
400 images resized ✓

• mogrify is an image-editing tool that edits files in place (overwrites the originals)

• *.jpg is a wildcard pattern meaning “all files ending in .jpg”.

Then renames and sorts each file

COMMAND:
mv IMG_0291.jpg ./output/shoes/SKU-1042-BLK.jpg
mv IMG_0292.jpg ./output/bags/SKU-2187-TAN.jpg
mv IMG_0293.jpg ./output/jackets/SKU-3301-NVY.jpg
... repeats for all 400 files

OUTPUT:
400 files renamed and sorted ✓

• 'mv' is the command for 'move' (which also renames the file when you move it to a new name)

Then it verifies the result before sending back to you

COMMAND:
ls -R ./output/ | head -20

output/shoes/
SKU-1042-BLK.jpg
SKU-1043-WHT.jpg
SKU-1044-RED.jpg
...(112 files)
output/bags/
SKU-2187-TAN.jpg
SKU-2188-BLK.jpg
...(89 files)

• On ‘ls -R ./output/ | head -20’. The | sends the output of one command into another, ‘head -20’ just means 'show me the first 20 lines.

It does all this in seconds. It would take you a couple of hours manually.

This is one CLI, called bash, the general-purpose command line that comes with your computer. But there are purpose-built CLIs for specific jobs too:

• Stripe CLI — pull revenue data, manage subscriptions, test payments

• Playwright — control a web browser: navigate, click, fill forms, take screenshots

• AWS CLI — spin up servers, manage databases, scale infrastructure

• Vercel CLI — deploy a website live in one command

Each of these is a separate tool an agent can use. The file organising example used one tool (bash). But give an agent the Stripe CLI too and now it can pull your revenue numbers. Add Playwright and it can browse the web. Add Vercel and it can deploy what it builds.

That’s what “tool use” means. The more CLIs you give an agent access to, the more it can do. Your job is to make sure it has the right ones for the task.

It all sounds a bit technical, and it is, but you’d only see those raw commands if you’re using a terminal or watching them fly by in tools like Claude Code. They’re present even when you don’t see them.

If an agent like Cowork is doing a task, you can click to expand what it ran and see the detail — like this example listing files to find recent fund updates.

Every agent is running commands like this under the hood. The interface just hides and abstracts them away.

Headlines

• Claude Code launched auto mode²⁰⁸, a middle ground between manually approving every action and skipping all permissions dangerously (how they designed it¹⁰⁹). Claude connectors for work tools are now available on mobile⁹⁵ too. They are also cooking something called auto-dream¹²⁷ for compacting memory overnight. Claude Code can now use iMessage to text you and others. (see docs²⁰⁰)

• Sora is shutting down¹¹³. OpenAI is killing its standalone video generation app along with the API. Its $1B deal with Disney is also cancelled as a result. The Information reports⁸⁵ that OpenAI is culling its side projects and focusing on a few key bets, with a new model codenamed Spud.

• ARC-AGI-3¹⁶⁹ launched with 135 mini games, nearly 1K levels, all human-solvable. But all models, when given basic prompts, score less than 1%. They have 25 games publicly available to play²⁵⁴ (as humans) and don’t tell anyone that I spent 4 hours on them yesterday.

• Google released the Pro version of Lyria 3¹³⁵, extending the music generation from 30 seconds to 3 minutes. It’s available in both the Gemini App and AI Studio for developers.

• The Figma canvas is now open to agents²⁵². You can now use AI agents to design directly on the canvas using the new use_figma MCP tool.

• Why Portkey is making its latest Gateway launch⁴¹⁸ completely open source⁹⁰.*

⁴¹⁸

My feed

• Chronicle⁴³⁴ – Cursor for slides. Turn ideas and notes into stunning, professional decks in minutes.*

• Paper Snapshot²⁰⁰ - Snapshot your live website and paste it into Paper as editable HTML/CSS layers.

• Ghostwriter by Sierra²⁰⁸ - Chat with an agent to build more agents.

• Mario, founder of the popular open source agent Pi, wrote a post yesterday, “Thoughts on slowing the fuck down²⁵⁹“, that says software quality appears to be declining as more companies rely on agents.

• Building CLIs for agents²⁴¹ - Eric from Cursor wrote a thread on making CLIs that actually work for agents. ElevenLabs has already made their CLI agent-friendly¹⁰⁹ using these tips.

• Building deep research that works from your CLI¹⁵⁹ with BrowserBase. (resulting code⁶⁵)

• Hark¹⁷⁸ – New AI lab from Brett Adcock (yes, the Figure robotics guy). 8 months in stealth, focused on "the most advanced personal intelligence" paired with next-gen hardware.

• GitHub has been going down wayyy too often these days. Plans to fix it¹¹⁵ and alternatives¹⁴⁴ are starting to show up.

• How USV built a team of internal agents¹²⁵ that live in their group email threads and learn from team feedback.

• Feynman²¹⁴ - Read papers, research and get cited meta-analysis for your question from your CLI.

• Brave registered the .agent TLD and is making it a community effort.²³⁷ I tried to reserve 10 domains 😬

• Lil Agents³²⁰ – Tiny AI companions that live above your dock. Each one has its own Claude session and mini window. Now open source¹⁰⁶. Adorable.

Afters

merch gifts have gone up a level ty @OpenAI

@bentossell¹⁶⁸

Since we all know that terminals are made for complex UIs... I decided to make T1Code (1T, because a terminal is all you need). I know @theo really likes this kind of complex UI right on the terminal... so lets hope he likes it!

@maria_rcks³⁰³

Cursor cloud agents can now run on your infrastructure. Get the same cloud agent harness and experience, but keep your code and tool execution entirely in your own network.

@cursor_ai⁹⁸

AI will help discover new science, such as cures for diseases, which is perhaps the most important way to increase quality of life long-term. AI will also present new threats to society that we have to address. No company can sufficiently mitigate these on their own; we will

@sama¹⁴¹

Introducing Expect Let agents test your code in a real browser 1. Run Claude Code / Codex to QA your app 2. Watch a video of every bug found 3. Fix and repeat until passing Run as a CLI or agent skill. Fully open source

@aidenybai¹⁴¹

Introducing the new dev-browser cli. The fastest way for an agent to use a browser is to let it write code. Just `npm i -g dev-browser` and tell your agent to "use dev-browser"

@sawyerhood¹⁸²

Announcing companies.sh - the open standard for Agent Companies Import and run entire companies with a single command Just run `npx companies.sh add <repo/company>` More 👇

@dotta

I updated my interactive subagents to free up the main agent to be interactive as well (basically /btw but just a normal continuation) and the subagent asynchronously returns its result to the starting session github.com/hazat/pi-inter…

@DanielGri⁸⁷

• Find me on X³⁷, Linkedin⁴², or YouTube³³

• Read about me⁴⁵ and Ben’s Bites

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Email us at shanice@bensbites.com³⁴ or k@bensbites.com³⁸