AI Agent Integration (WebMCP)
Who's In? supports WebMCP — the W3C browser standard (Feb 2026) that lets AI agents discover and call structured tools natively in Chrome 146+.
## What is WebMCP?
WebMCP (Web Model Context Protocol) is a W3C Community Group draft standard that gives websites a browser-native API — `navigator.modelContext` — to register callable tools for AI agents. Instead of agents scraping HTML, they call tools directly using structured JSON. This means 89% fewer tokens and no brittle CSS selectors.
## Available Tools
Who's In? registers three read-only tools:
| Tool | Description | |------|-------------| | search_events | Find events by keyword, location, or date range | | get_event_details | Get full event data by ID or URL slug | | check_availability | Check capacity and waitlist status |
All tools are read-only. Write actions (RSVP, event creation) always require explicit user confirmation — agents cannot act on your behalf without your direct approval.
## Which AI agents can use these tools?
- **Claude** (Anthropic) — computer use / browser agent
- **ChatGPT** (OpenAI) — browser extension
- **Gemini** (Google) — browser agent
- **Perplexity** — browser-based
- Any agent built on Chrome 146+ with WebMCP DevTrial flag enabled
## How to use it
- 1. Open Who's In? in a browser-based AI agent
- 2. Tools are : auto-discovered** — no setup needed
- 3. Ask the agent to search events, check availability, or get event details
- 4. For any RSVP or booking, you confirm the action yourself
## REST API alternative
Prefer a REST API? Our full OpenAPI 3.1 spec is available at [/api-docs](/api-docs) with 100 req/min rate limit and no auth required for read endpoints.
## Browser requirements
- Chrome 146+ with "Experimental Web Platform Features" flag enabled (during DevTrial phase)
- A polyfill (`mcp-b`) is available for other browsers
- HTTPS required (all Who's In? pages are served over HTTPS)
## More information
Read the full blog post: [Who's In? Becomes the First Event Platform with WebMCP Integration](/blog/webmcp-event-platform)
