WebMCP lets a web page give AI agents JavaScript tools through a registerTool() API in the browser, so an agent can act on a site through functions the site defines rather than by scraping. It is a draft Community Group report and the planned deliverable of a proposed W3C Agentic Web Working Group.
WebMCP
WebMCP lets a web page give AI agents JavaScript tools through a registerTool() API in the browser, so an agent can act on a site through functions the site defines rather than by scraping. It is a draft Community Group report and the planned deliverable of a proposed W3C Agentic Web Working Group.
Where it stands
As of 2026-10-13, the Agentic Standards Map records:
Draft Community Group Report, dated 9 October 2026 on the page read on 2026-10-13 (2026-09-30 on 2026-10-03), no numbered version; on 2026-10-08 PR #338, “Remove declarative API from spec”, was merged (the specification now focuses on the imperative registerTool() API); the draft Agentic Web Working Group (WG) charter lists WebMCP as its normative deliverable.
Why it matters to agents
Draft: “The WebMCP API enables web applications to provide JavaScript-based tools to AI agents.”; an editor wrote on 2026-09-25 that identity and delegation proposals “are beyond the scope of the simple WebMCP API”.
Sources
- https://webmachinelearning.github.io/webmcp/
- https://github.com/webmachinelearning/webmcp/issues/257
- https://github.com/webmachinelearning/webmcp/pull/338
- https://github.com/WebKit/standards-positions/issues/670
Status and relevance quoted, shortened, from the Agentic Standards Map by Francesco Marinoni Moretto, CC BY 4.0, https://frmoretto.github.io/agentic-standards-map/. The full entry, with every dated source, is in map.json under w3c-webmcp-cg-report.
Industry: cross-domain
Related standards
Standards this one builds on, supersedes, profiles or is commonly deployed beside.
