Customaise: The web wasn't built for you. Fix that.
Customaise is a free Chrome extension for UserScripts and AgentScripts. Rewrite any website in plain language. Open every site you're signed into to your AI agent. Every change is local, reversible, and versioned. Customaise is the interface layer between any site and any AI agent.
Reshape any page
Describe the change in plain language. Customaise writes a reversible tweak under the hood, applies it to the live page, and brings it back every time you return. Inbox that dims promotions, feed that kills the sidebar, CRM that sorts itself, dashboard that hides the metrics you don't track. The web, rewritten one script at a time.
Create any tool for your AI
Build AgentScripts the same way you build UserScripts: describe what you want, Customaise writes the tool, your AI agent calls it through the WebMCP standard. Archive the inbox. Place the trade. Export the lead. Book the flight. Your agent, fluent in your sites. Tools run in your already-signed-in browser session with per-call consent on anything sensitive.
How it works
Type a sentence describing what you want changed or what tool you want your agent to have. Customaise's AI writes the script, validates it through a security-hardened sanitisation pipeline, and applies it live. Every script is editable in a full Monaco-powered editor with version history. Every change is reversible. Build for yourself, build for your AI agent, or install ready-made scripts from the Customaise Marketplace.
Key features
- UserScripts in plain language: describe the change, Customaise writes it, you approve it before it runs
- AgentScripts for your AI: typed, consent-gated WebMCP tools your agent can list and call on any site you're signed into
- Script Editor: full Monaco-powered editor with syntax highlighting, version history, and live validation
- Cross-Device Sync: keep UserScripts and AgentScripts in sync across every browser you use
- MCP Server for your IDE: expose your authenticated browser session to Cursor, Claude Code, Codex, and any MCP client
- Local-first: scripts run in your browser, your session stays yours, your data never leaves your machine without consent
- Reversible: every change is versioned and revertible; nothing is permanent
- Marketplace: install community-reviewed scripts with one click, with publisher control and update-on-publish
Built for IDE agents
Cursor, Claude Code, Codex, Antigravity, Kiro, and every other MCP client can list and call AgentScripts on the pages you have open. The MCP server runs on your machine, talks to the Customaise extension locally, and uses your existing IDE subscription for the LLM, so Customaise has no per-call AI cost. Cheaper than a vision LLM driving a headless browser, faster than agent-browser cloud platforms, and your real session stays yours.
Pricing
Start free with 200K monthly in-browser AI tokens and the MCP Server bridge for your IDE (50 calls/day, 150 per rolling 7-day window). Free includes the whole toolkit: unlimited UserScripts and AgentScripts, the Script Editor, the marketplace, basic AI models. Upgrade to Power User ($9/month, £7/month, €9/month or pay annually) for unlimited MCP calls, BYOK with your own Gemini API key, cross-device sync, and marketplace publishing. A 7-day Power Trial is included on every account with no card required.
Get started
Add Customaise to Chrome for free and start reshaping the web to fit you. Or read the UserScripts guide, the AgentScripts guide, or browse the marketplace of ready-made scripts from the community.