Reticle

Your AI agent says "done." Reticle finds out if that is true.

It drives your real, running app and reads what happened. Then it returns a verdict, pass · fail · cannot tell, with the file:line to fix.

Ask questions, see what we build, and help decide what ships next.

The problem · Demo · What Reticle does · Install · Use it · Community · vs Playwright · Benchmarks · Safe to install · Docs

⭐ Star the repo · Good first issues · Contribute

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The problem

Your agent writes code, assumes it worked, and moves on. It never opens the app.

So the broken modal, the silent 500 and the "Deploy succeeded" over a failed deploy all ship. You find them later, by clicking around. You are now your agent's QA.

The truth was in the running app all the time. It did not reach the screen.

Your agent did not forget a step. A coding agent is built to produce a change, so it is optimistic by design. Verification does the opposite: it goes to find out, and is ready to come back with no.

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Demo

▶ An agent says its fix works. Reticle catches the double charge it missed. Click for the full demo.

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What Reticle does

Reticle puts a small, dev-only SDK inside your app. Your coding agent gets tools to look, act, observe and assert through it. Reticle reads the app from the inside. So it sees what the screen hides: the request a click sent, its response, the app state, the console and each element's source line. Every check ends in a verdict with the evidence attached.

• A verdict, not a screenshot. verified: "yes", "no" or "unknown" (cannot tell). The verdict includes the request, state change and console line that decided it, and the file:line to open.
• Sees what the screen hides. Network responses, each tied to the click that caused it. Your store's real state (zustand, Redux, TanStack Query, Pinia and more). Console errors, request counts and React renders.
• Says when it cannot tell. Only yes is a pass. A check that cannot decide returns unknown with the reason. It never gives a quiet green.
• Flows that replay with no AI model. Say "save that as a flow". After that, one call re-verifies that journey deterministically. Today's fix cannot quietly break last week's feature.
• A gate in CI. reticle gate fails a change that touches a saved flow's code without a new passing run.
• The Harness (optional, on the platform): describe a person and a journey. Reticle drives it, verifies each step and saves what passed. How it works.
• A HUD in your page to watch the agent work: every action, every verdict, the flows it saved, and notes you pin for it.
• Works with your agent: Claude Code, Cursor, Codex, Windsurf, VS Code, Gemini CLI and anything else that speaks MCP. Web (React, Next.js, Vue, Svelte, Angular and more) and desktop (Electron, Tauri).
• Safe to leave installed. Production builds do not include the SDK. The bridge listens only on 127.0.0.1. Nothing from your app leaves your machine unless you link a project.

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