Install WebMCP

Add the WebMCP script to your pages with the paste-in snippet or from your own JavaScript, and its options.

The snippet (most sites)#

Paste this into every page of the websites you listed. The <head> or the end of <body> both work.

html 
<script id="webmcp-embed-script" src="https://js.subcontext.com/webmcp-latest.js"
        data-key="wmk_YOUR_KEY" async></script>

When it loads, the script reads your key, asks Subcontext (https://subcontext.com) which tools your integration offers, and registers each one with the browser. It waits for the page to finish loading first if it needs to.

  • You can use async or defer, or add the tag from your own JavaScript (for example through a tag manager).
  • Keep id="webmcp-embed-script". It helps the script find its own tag in every case.
  • webmcp-latest.js always gives you the latest version. Browsers cache it for up to 5 minutes. If you need a fixed version that never changes, ask Subcontext.

From your own JavaScript#

To decide when the tools are offered (for example only after a visitor agrees to it), load the script without data-key. It then does nothing until you call init:

html 
<script src="https://js.subcontext.com/webmcp-latest.js"></script>
<script>
  SubcontextWebMCP.init({ key: 'wmk_YOUR_KEY' }).then(function (result) {
    if (result.ok) console.log('Tools offered:', result.tools)
    else console.log('Tools not offered:', result.status, result.error)
  })
</script>

Use one or the other. If the tag has data-key and you call init, the one that runs last wins, and the other reports cancelled.

Options#

On the script tag#

Attribute What it does Default
data-key Your integration's key (starts wmk_). The script starts by itself only when this is there. Without it, the script waits for you to call init. none
data-debug Set to "true" to log extra detail in the console: the tool list request and what came back, each tool registered, and each tool call with its input and its result or error. These are debug messages, so set the console to show the Verbose level. Only the exact text "true" turns it on. off
data-base-url Where to send requests. You don't normally need this. https://subcontext.com
id="webmcp-embed-script" Not an option. It helps the script find its own tag. Keep it.

SubcontextWebMCP.init(options)#

Option Type What it does Default
key string Your integration's key. Required. none
debug boolean Same as data-debug. false
baseUrl string Same as data-base-url. A trailing slash is ignored. You don't normally need this. https://subcontext.com

There are no other options. Which tools are offered, and their names, descriptions and inputs, all come from the integration in the dashboard.

Stuck, or something missing?

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