Careers WebMCP

OpenAI WebMCP Challenge entry: a careers site with 18 WebMCP tools. The agent searches, navigates and fills in your application; only you can press Submit.

WebMCPTypeScriptNext.jsReactPlaywrightVercel

The careers page is the connector.

One of four entries Allison submitted to OpenAI's WebMCP Challenge on 3 September 2026, alongside the winning JupyterLite WebMCP, Swagger UI WebMCP and Strudel WebMCP. All of them were built in under 48 hours from long written contracts handed to coding agents.

Careers WebMCP is a normal careers site for a fictional employer, Northwind. When the browser supports WebMCP, the site registers 18 candidate-side tools. The agent can answer compound questions the filter UI can't ("staff or above, SF or remote, at least $220k"), type that query into the site's own search box, open real pages in your tab, co-edit an application draft with you, and pre-fill sign-up.

An agent has pre-filled a job application draft on the Northwind careers site; the person's own cover note sits in the form and the draft revision counter shows under the title.

The agent fills in; you press Submit

No submit, no sign-up. careers_submit_application runs the same validation as the button, opens the draft, highlights Submit and returns awaiting_human_confirmation. Creating an account works the same way: the tools module imports the sign-up form's field store, but not the function that actually creates a session.
Your edits win. Every agent write carries the revision it last read. If you've typed since then, the write is refused with STALE_APPLICATION, so your cover note can't be clobbered.
One code path. Agent search runs the same deterministic scorer as the visible list, so the page and the agent can't disagree about what matches.
Exports by handle. Instead of pulling twenty job descriptions into the agent's context, it creates a CSV export and pages through it.
Presence without injection. Agent activity shows up in the real UI, but the captions are built from counts and enums only, never from site text. A prompt injection hidden in a job description has nowhere to land.

The pre-filled sign-up form, noting that nothing is created until you press Create account.

Application submitted confirmation, reached only after the person pressed Submit themselves.

Try it

The live site works without an agent. The tools need ChatGPT's in-app browser or Chrome with experimental web platform features turned on.

The live Northwind careers site: Open Positions Worldwide, with search, filters and 20 open positions.

The live site, captured September 2026.

The careers UI is built on the MIT-licensed Baalvion Jobs Portal (provenance is in the repo's NOTICE); the WebMCP layer is what this project adds. There's a demo video and the Devpost entry. MIT.