Show your agent exactly what you mean.
Draw numbered boxes on your screen, annotate what to fix, and send to Claude Code, Cursor, Grok, or any agent that accepts images.
7-day free trial / $29 once after / annotations stay local
How it works
Three steps. Any agent.
Draw what you mean on screen, write a short instruction, and paste into Claude Code, Codex, Cursor, or whatever you use next.
Open the overlay
Invoke Casso and a transparent overlay covers the screen.
Draw numbered boxes
Drag regions over the UI you care about. Optional notes. Numbered [1], [2], [3] automatically.
Send to your agent
Confirm to capture. Annotated image and prompt land on the clipboard - or paste straight into your agent.
Features
The missing visual layer for coding agents.
Agent-agnostic by design
Claude Code, Codex, Cursor, Grok CLI, or anything that accepts an image and a path. Casso doesn’t care which agent you use today - or tomorrow.
Numbered regions that stick
Full screenshot, per-box crops, and an annotated composite. Your prompt references [1], [2] - the agent sees exactly what you pointed at.
Annotations stay local.
Sessions write under a local temp path. Screenshots never leave your machine - no telemetry, no cloud model in the middle.
Auto-paste into the terminal
Allow accessibility permissions and Casso pastes the prompt into your frontmost CLI. Skip them and you still get a perfect clipboard handoff.
Pricing
Try it free for 7 days. Keep it forever.
Full product while you try it, then one personal license for Mac and Windows. No seats, no usage meter, no subscription.
Trial
7-day full access
- Full annotate access for 7 days
- Starts when you sign in on the desktop app
- Same features as the personal license
- Annotations stay local - never uploaded
Account + sign in on the app to start annotating
Personal
Keep Casso for good
- One license / Mac and Windows
- Unlimited annotations & sessions
- Auto-paste into terminal (optional)
- Works with every vision-capable agent
- Annotations stay local - never uploaded
- Free updates for the entire 1.x line
One license / Mac and Windows / free 1.x updates
FAQ
Straight answers.
Built for people who already live in a terminal with an agent open.
Explore
Guides and agent pages
Deep dives on Claude Code, Codex, and how visual context actually works for coding agents.
Claude Code
Numbered boxes and paste-ready prompts for Claude Code.
OpenAI Codex
Visual context for Codex without agent lock-in.
Annotate for Claude Code
Step-by-step handoff patterns that land on the first pass.
Annotate for Codex
Mark regions, write short notes, paste into Codex.
Cursor
Show Cursor exactly which UI region to fix.
Grok CLI
Numbered regions for Grok CLI and mixed-agent days.
Visual context guide
How to feed coding agents clear visual context in 2026.
Comparisons
Casso vs Agentation, CleanShot, SlimSnap.
Stop describing the UI.
Point at it.
Casso is the visual layer between your screen and every coding agent you already pay for. Try it free for 7 days - keep it for $29 once.
One hotkey: ⌘⇧A