WebMCP

Dear colleagues,

The W3C Team (staff) have asked for our input to the discussion about
whether WebMCP should be adopted as official W3C work. We have discussed
different aspects of this a couple of times recently in the main APA WG
call, and I'm in the process of tying those threads together, and hope to
have one possible proposed comment for your consideration by this week's
main APA WG meeting.

However, regardless as to whether you attend the main APA WG meetings or
not, it would be great if you could read some of the following, and share
your thoughts. I will try to reflect them in any proposed comment that I
submit for APA WG's consideration. We will be discussing these again on this
week's main APA WG call.

Perhaps the key thread is the one regarding the relationship between WebMCP
and the accessibility tree - there's a fundamental question as to whether
the accTree is the right place to add semantics, and there are concerns on
either side as to the results of doing, or not doing, so.

Note for people who don't regularly attend APA WG review calls: the links to
'tracking threads' are links to issues in APA's space, where APA members are
encouraged to natter and co-ordinate, before proposing comments. To get to
the source issues, follow the link from the first comment of the tracking
issue. The benefit of the layer of indirection is we can talk about an
issue, and develop APA consensus around it, before commenting as APA WG on
the public thread. You're still welcome to comment on the public threads as
individuals.

* WebMCP explainer:
<https://github.com/webmachinelearning/webmcp/blob/main/README.md>
* Tracking issue for WebMCP accessibility considerations:
<https://github.com/w3c/a11y-tracking/issues/318>
* Tracking issue for 'Redundancy with accessibility tree' thread:
<https://github.com/w3c/a11y-tracking/issues/317>
* Standards positions of the three main engines:
  - Chromium/Chrome: Supportive
  - Gecko/Mozilla Firefox: No official position yet; thread:
<https://github.com/mozilla/standards-positions/issues/1412>
  - WebKit/Safari: Opposed; position thread:
<https://github.com/WebKit/standards-positions/issues/670> and the specific
comment where they state their objections is:
<https://github.com/WebKit/standards-positions/issues/670#issuecomment-46084
32694>

The explainer starts with a good intro as to what WebMCP is.

Thanks for your time, and any input you may have! Feel free to share via
this email, or via the a11y-tracking issues linked above (on the threads in
the a11y-tracking repo, not the source repos).

best regards,


Matthew

Received on Monday, 29 June 2026 22:00:46 UTC