WebMCP Challenge – OpenAI
openai.com19 points by tilt 6 hours ago
19 points by tilt 6 hours ago
I don’t understand the point of WebMCP. Any website that you could do interesting things with programmatically either already has an API or doesn’t want to provide programmatic access for business reasons. So who is this for?
I don't think it's that binary. For the majority of websites, adding programatic access didn't make sense because it would primarily have been for scraping data. No financial incentive for them to support this.
The dream today is that agents might prefer your website due to it's MCP and actually purchase something. i.e. 'hey claude go find me the cheapest places I can buy these headphones'
I assume it’s for one-off cases that you encounter while agents scrape/browse with a goal in mind.
If you care about web standards, please for the love of god do not participate in this challenge. “WebMCP” is an extension to the `document` global under `document.modelContext`. The `document` object exists to represent the visual and structural node tree of an application. The `modelContext` extension is essentially an API gateway, and this proposal staples a global RPC registry with structured JSON payloads onto the DOM. It ignores the standard Request/Response API, and it does all of its work on the main thread. It forces developers into manual state-synchronization hell just to maintain a facade for a screen-scraping LLM, meeting them halfway so increasingly capable bots can “book flights on your website.” The API makes no considerations for API versioning, so any WebMCP tools you write are carved in stone.
I have no idea who at Google is advocating for this, but it’s a half-baked idea that goes against 20 years of web standard work. At least put this under the `window` or `navigator` global, goddamn.