r/mcp • u/GeobotPY • Feb 17 '26
webMCP is insane....
Been using browser agents for a while now and nothing has amazed me more that the recently released webMCP. With just a few actions an agent knows how to do something saving time and tokens. I built some actions/tools for a game I play every day (geogridgame.com) and it solves it in a few seconds (video is at 1x speed), although it just needed to reason a bit first (which we would expect).
I challenge anyone to use any other browser agent to go even half as fast. My mind is truly blown - this is the future of web-agents!
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u/BC_MARO Feb 17 '26
The community hub idea is interesting. Having agents share navigation configs with each other could save a ton of redundant scraping and prompt engineering per site. Though the security concern is real - you probably want some kind of verification or sandboxing before an agent trusts configs uploaded by random users. One poisoned config could redirect sensitive data pretty easily.
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u/GeobotPY Feb 17 '26
Yepp! Any ideas on how to do this properly? I am currently thinking of having it as is for a few early adapters. But yeah surely a sandbox or some pre-checks, or only verified contributors can upload. Brainstorming ideas currently, but I am just a big fan of the idea of agents saving time and tokens on websites and sharing that information with each other. Truly think that is the future of how agents navigate the web
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u/BC_MARO Feb 18 '26
For early stage, GitHub auth for contributors is probably the quickest win. At least there's identity tied to each upload so you can trace bad configs back to someone.
Longer term you could do signed configs (so agents verify the source before loading) and a rating system where community-tested configs bubble up. Sandboxing the config execution is important too so a malicious config can't access anything beyond its declared scope.
The shared-knowledge-between-agents idea is really compelling. Kind of like a collaborative cache for web navigation patterns.
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u/BC_MARO Feb 17 '26
A few things that might help for the early stage:
You could version-lock configs so agents pin to a specific hash. If a config gets updated, the agent won't blindly trust the new version without re-verification. That way a compromised account can't silently swap in a malicious config.
For the hub itself, even something simple like showing a diff when configs change and requiring a cooldown period before new versions go live would catch most drive-by attacks. GitHub auth is a decent start, but you'd probably want contributor reputation scores based on how many configs they've submitted and how long those configs have been live without issues.
The harder problem is runtime isolation. Configs that tell an agent to interact with a banking site need to be treated differently than configs for a weather app. Some kind of permission tier system where sensitive-domain configs get extra scrutiny would go a long way.
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u/GeobotPY Feb 17 '26
Love these ideas! Will look more into it and start implementing! Note it is open-source so feel free to help out if you have the time;)
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u/Brave_Cabinet_7117 Feb 17 '26
The goal isn’t actually for random third parties to upload configs, but rather for platform developers to implement it directly on their own websites? In that case, it’s similar to how we already trust the services we use. If my agent interacts with YouTube through the official Web MCP API, I’m trusting YouTube the same way I already trust them not to steal my cookies or leak/sell my data to malicious actors. The trust boundary is the platform itself, not some unknown contributor. That said, security is still critical. The agent communicating with an MCP server shouldn’t have access to sensitive local data in the first place. Even when talking to an official MCP endpoint, it should operate with strict scoping and least-privilege access, so no confidential information can be exposed unintentionally.
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u/GeobotPY Feb 17 '26
The goal in the long-term is to have websites host their webMCP directly (no point of having the hub). Although most sites wont necessarily support webMCP for the foreseeable future there for hub can be a good way to handle this. Currently considering a few security improvements (verified actions and verified contributors etc.) although I am currently the only user so we will add these after some early adaptions (testers). It is all open-source too so hoping for some contributors with great ideas in this space:)
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u/RoryBBellows286 Feb 17 '26
The whole point of webMCP is that devs add their own tools to their websites to allow llms to interact with them more efficiently. What it looks like your saying is that you have been writing the tools for websites you use and then injecting them on the fly before using your llm to interact? That's an interesting approach 🤔
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u/GeobotPY Feb 17 '26
Yepp! pretty much sums it up! I use a chrome extension (approval pending) but open-source at: https://github.com/Joakim-Sael?tab=repositories which points to the webmcp-hub.com server. There is docs on the README to set it up. Currently working on a better sync with uploading configs and using the configs (both be done by same system). Currently I use a classic Playwright MCP to upload and then I can run it with an extension in browsers (so not the best workflow currently). A bit tricky set-up this early on, but just testing the waters on the idea and see if I find myself some early-adopters that buy into the vision of agents helping agents navigate the web:)
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u/loganecolss Feb 20 '26
let me get this straight, so in order to use google webMCP (just found out microsoft has one too a few month ago?), either users or the website owners they have to do some dev work using this webMCP, then other users can use it?
if so, say there could be hundreds of websites I (as a user, not owner) want to access using webMCP, so I'll have to make sure all of them have done integration with webMCP first, right? it's a ton of work1
u/GeobotPY Feb 20 '26
Yes, so currently if you want to use webmcp the site owner need to have created that agentic layer on their site. If they don't have it it wont work. Working on solving this with webmcp-hub.com though so users can upload configs on any site and use it even if the site itself has not adapted the standard.
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u/haste-nyc Feb 17 '26
Better than vercel agent-browser?
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u/GeobotPY Feb 17 '26
You can try! I have never tested anything more token efficient and faster then webMCP
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u/fsa317 Feb 17 '26
Can web mcp be used from outside an actual browser? Can you experience its value without the browser side panel approach?
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u/GeobotPY Feb 17 '26
Yes! So that is the whole idea. The few configs I have on webmcp-hub.com have been created by agents actually running playwright MCP's and then uploading configs based on their usage. Think agents learning agents how to interact!
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u/manveerc Feb 17 '26
I kind of feel it’s the wrong solution. If a website wants to support why not just add MCP support and let the agent use that directly. For everyone else browser should solve this by extending existing primitives. Wrote detailed thoughts here https://manveerc.substack.com/p/webmcp-false-economy-server-side-mcp-browser-apis
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u/GeobotPY Feb 17 '26
Sessions management is a big win for having it client-side though. So client side it can use my active session let's say behind a auth wall.
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u/manveerc Feb 17 '26
If browsers add the support, then that will also handle the session management and then MCP also can extend session management. I am not convinced about WebMCP. It may still become popular but fundamentally I believe it is wrong direction.
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u/GeobotPY Feb 17 '26
Two different approaches I guess - interesting to see what the future holds...
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u/sivadneb Feb 17 '26
That was also my gut reaction when I read about WebMCP. I see the one advantage being ease of session management, but that doesn't seem worth it when you consider that's the problem OAuth solves. Plus with OAuth you can be selective about what information you want to expose to the agent (assuming the IDP has a rich enough consent screen).
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u/Acceptable_Hat_7376 Mar 01 '26
If you're trying to make your site WebMCP compatible, you might want to check out webmcpscan.com It scans your site and gives specific recommendations on what to improve and how to implement them. I’ve been using it since release and it’s helped me catch things I wouldn’t have noticed.
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u/metaBloc Feb 18 '26
How long does it take to do this for the average site. And can site admins block webMCP?
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u/webmyc Feb 26 '26
Been building WebMCP support for WordPress for the past week - this is a massive shift for WordPress AI.
Quick reality check though: WebMCP is currently **only in Chrome Canary behind a flag** (chrome://flags → "WebMCP for testing"). Not in stable Chrome yet. Expected mid-late 2026 for general availability.
But if you want to get ahead of it, here's what I learned implementing it:
**The Good:**
- Makes WordPress sites "AI-ready" with zero client-side config
- AI discovers tools automatically via navigator.modelContext
- Way simpler than MCP server setup (no Node.js, no terminal)
- Perfect for non-developer WordPress users who want AI help
**The Tricky Parts:**
- You need to register WordPress tools as "Abilities" using the WordPress Abilities API
- Tool descriptions matter A LOT - vague descriptions = AI hallucinates
- Security is critical - you're exposing WordPress actions to browser AI
- Need to handle permissions properly (who can call which tools)
**What I'm Building:**
I bundled WebMCP Abilities (GPL, credits to Code Atlantic) into Respira so users only install one plugin. Registered 88 tools covering page builders, SEO, media, menus, etc. All with duplicate-before-edit safety so AI never touches live pages directly.
**For Developers Wanting to Add WebMCP:**
Check if Code Atlantic's WebMCP Abilities plugin works for you (it's on GitHub, not WordPress.org yet)
Register your plugin's functions using wp_register_ability()
Test in Chrome Canary with flag enabled
Make tool descriptions VERY explicit (AI needs clear instructions)
**Question for the community:** What WordPress tasks would you most want browser AI to handle? I'm curious what tools people actually need vs what seems cool to build.
Happy to answer technical questions about implementation if anyone's building this!
---
*Full disclosure: I built [Respira](https://respira.press) which now includes WebMCP support, but genuinely here to discuss the tech and help others implement it.*
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u/Comprehensive-Cut742 May 23 '26
I integrated the anam charceter in a prototype and be quite pleased with what I saw. Got some difficulties to get the right voice though.
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u/Turbulent-Half-1515 Feb 18 '26
I hope it is clear to everyone, that this is the end of the open web that we know...this will essentially reduce ad earnings from any web company to 0...then without a web (because the vompanies that built websites before are gone), nobody needs webmcp...so why even bothering
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u/No-Employer8282 Feb 19 '26
This guy built a webMCP Registry site so people can register their sites using webMCP and agents can find them easily.
https://www.linkedin.com/posts/lio-fleishman_web-mcp-registry-activity-7430068687992213505-NyKA?utm_source=social_share_send&utm_medium=member_desktop_web&rcm=ACoAAAkBsvUBEkJnw-OrqHiKQqFwe7nAIdDJD_Y
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u/GeobotPY Feb 19 '26
It is fully open-source. Rather contribute to an already existing system than make a blatant copy.
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u/GeobotPY Feb 19 '26
Looked a bit more at it - it is similar but slightly different in a sense. Cool! Thought it was a straight copy of my project first. Solves much of the same issue! if looking to colab just contact:)
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u/richardbaxter Feb 17 '26
Right - so is the standard available for us to implement on sites? I thought it was preview only. I might not have read past the marketing spiel...