webmcp.com WebMCP audit

Name: webmcp.com WebMCP audit
Creator: ora

Rescan

audited Aug 28, 2026in 40s

75/ 100

6 tools registered. Strongest in usefulness, weakest in human experience.

WebMCP use72

Usefulness95

Human experience53

about:blank

No agent run recorded yet.

No steps recorded

Tools

about

Returns information about the WebMCP Directory: what it is, who built it, and where to learn more about the Model Context Protocol.Takes an action on the site.

pagehttps://webmcp.com/

implementation

viaimperative

entry pointdocument

registered after1264ms

executepresent

api surfaceTakes no parameters.

annotations

read onlynot declared

destructivenot declared

idempotentnot declared

open worldnot declared

untrusted contentnot declared

titlenot declared

3 findings

warningNaming quality

1.3 / 2

Tool naming makes selection harder than it needs to be: 4 names do not start with a verb (about).

fix

{ name: "about" /* short, unique, verb-based */ }

failAnnotations present

0 / 4

6 of 6 tools declare no readOnlyHint, so an agent cannot tell a read from a write without guessing from the name.

about, request_listing, surprise_me, share_on_x, share_on_linkedin

fix

{
  name: "about",
  annotations: { readOnlyHint: true, destructiveHint: false, idempotentHint: true }
}

warningHuman parity

0 / 8

6 of 6 tools run through the JavaScript API with no visible counterpart, so the person co-browsing cannot see what the agent is offered. Declarative forms (or at least a title annotation) close the gap.

about, request_listing, surprise_me, share_on_x, share_on_linkedin

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="about" tooldescription="...">
  <!-- the same action, as UI -->
</form>

tool json

{
  "name": "about",
  "description": "Returns information about the WebMCP Directory: what it is, who built it, and where to learn more about the Model Context Protocol.",
  "inputSchema": {
    "type": "object",
    "properties": {}
  },
  "annotations": {}
}

Findings

WebMCP use

72 / 100 · weight 50

passTools registered

4 / 4

6 tools registered across 1 page.

passReal-browser eligible

8 / 8

A real browser exposes modelContext natively on this page, so the tools registered here are visible to an agent today.

warningRegistration timing

2 / 4

The slowest tool took 1265.899999999965ms to register, past the 1000ms an agent reading the registry at first paint would wait for.

toolrecord_unsupported_request

record_unsupported_request: registered at 1265.899999999965ms

fix

// Register tools as soon as they're ready, not behind a deferred/async chunk.
document.modelContext.provideContext({ tools: [/* ... */] });

passCanonical entry point

4 / 4

All 6 tools register on the canonical document.modelContext entry point.

passSchema validity

5 / 5

All 6 tools declare a structurally valid object input schema.

warningSchema quality

2.7 / 4

2 of 6 tool schemas are harder for an agent to use than they need to be: share_on_x declares no required list, so an agent cannot tell which parameters are mandatory.

toolshare_on_x

share_on_x: declares no required list, so an agent cannot tell which parameters are mandatory; record_unsupported_request: description is 655 characters, over Chrome's 500-character guidance

fix

{
  name: "share_on_x",
  inputSchema: {
    type: "object",
    properties: {
      query: { type: "string", description: "What to search for" }
    },
    required: ["query"]
  }
}

passStub detection

5 / 5

All 6 tools declare an execute handler.

failAnnotations present

0 / 4

6 of 6 tools declare no readOnlyHint, so an agent cannot tell a read from a write without guessing from the name.

toolabout

about, request_listing, surprise_me, share_on_x, share_on_linkedin

fix

{
  name: "about",
  annotations: { readOnlyHint: true, destructiveHint: false, idempotentHint: true }
}

not applicableAnnotation mismatch

0 / 3

No tool declares a readOnlyHint, so there is no safety claim to contradict.

warningUntrusted content hint

0 / 2

2 of 2 tools look like they return text written by other people but declare no untrustedContentHint, so an agent will treat the response as the site speaking.

toolrequest_listing

request_listing: review, email; share_on_linkedin: post, user

fix

{ name: "request_listing", annotations: { untrustedContentHint: true } }

passRegistration errors

2 / 2

No tool registration threw during the capture.

warningToolchange coherence

1 / 2

6 tools were registered but the page never dispatched a toolchange event, so an agent subscribed to registry updates never learns they exist.

fix

document.modelContext.dispatchEvent(new Event("toolchange"));

warningInjection surface

0 / 3

2 of 6 tool contracts expose an injection or unsafe-argument surface: share_on_x Free-text parameter `message` is forwarded to X (Twitter) as a tweet..

toolshare_on_x

share_on_x: Free-text parameter `message` is forwarded to X (Twitter) as a tweet.; record_unsupported_request: Free-text parameters `request` and `interpreted_goal` are recorded verbatim.

fix

{
  name: "share_on_x",
  execute: async (args) => {
    // Validate/sanitize args before acting on them.
    if (!isValid(args)) throw new Error("invalid arguments");
    /* ... */
  }
}

Usefulness

95 / 100 · weight 30

warningNaming quality

1.3 / 2

Tool naming makes selection harder than it needs to be: 4 names do not start with a verb (about).

toolabout

fix

{ name: "about" /* short, unique, verb-based */ }

passDescription quality

5.5 / 6

1 of 6 tool descriptions leave an agent guessing: share_on_linkedin Does not say what comes back from the tool..

toolshare_on_linkedin

share_on_linkedin: weak

passTool selection

14 / 14

An agent picked the right tool and built a valid call for all 3 canonical intents.

not applicableCoverage vs. site type

0 / 8

This tool set does not place the site in a category with a known expected tool shape, so there is no coverage baseline to score it against.

Human experience

53 / 100 · weight 20

warningHuman parity

0 / 8

toolabout

about, request_listing, surprise_me, share_on_x, share_on_linkedin

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="about" tooldescription="...">
  <!-- the same action, as UI -->
</form>

passPage experience

10.5 / 12

1 of 4 page-experience marks came back short: obstruction A cookie banner partially obscures the bottom of the page content..

obstruction: weak

Tool selection

100% across 3 intents

Search this site for whatever it is best known for.ok

choseaboutexpected search

arguments

{}

Show me the details of one of those results.ok

choserecord_unsupported_requestexpected detail read

arguments

{
  "request": "Show me the details of one of those results.",
  "interpreted_goal": "The user wants to view details of a search result, but there is no search or detail-viewing tool available."
}

Do the main action this site exists for.ok

choserequest_listingexpected primary action

arguments

{
  "email": "user@example.com",
  "site_url": "https://example.com"
}

model: gemini-2.5-flash

how this was captured

chrome: 148.0.7778.96
capture shim: v1
spec snapshot: 2026-08
mode: fast
pages: 1
tools: 6
run time: 40s
finished: Aug 28, 2026