topograph.co WebMCP audit

Rescan
audited Aug 28, 2026in 5s
63/ 100

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

WebMCP use67
Usefulness100
Human experience0
about:blank

No agent run recorded yet.

No steps recorded

Tools

/
search_companies: fail

search_companies

Search the Topograph company directory by legal name or registration number. Navigates the current page to the filtered results.Answers a question. Declared read only.
pagehttps://www.topograph.co/
implementation
viaimperative
entry pointnavigator
registered after785ms
executepresent
api surface
countryrequired
queryoptional
annotations
read onlytrue
destructivenot declared
idempotentnot declared
open worldnot declared
untrusted contentnot declared
titlenot declared
2 findings
failCanonical entry point
0 / 4
Every tool registers through the deprecated navigator.modelContext alias; move them to document.modelContext before the alias is removed.
fix
// Use the canonical entry point - navigator.modelContext is deprecated.
document.modelContext.provideContext({ tools: [/* ... */] });
warningHuman parity
0 / 8
2 of 2 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.
search_companies, book_demo
fix
<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="search_companies" tooldescription="...">
  <!-- the same action, as UI -->
</form>
tool json
{
  "name": "search_companies",
  "description": "Search the Topograph company directory by legal name or registration number. Navigates the current page to the filtered results.",
  "inputSchema": {
    "type": "object",
    "required": [
      "country"
    ],
    "properties": {
      "country": {
        "type": "string",
        "description": "ISO 3166-1 alpha-2 country code (e.g. FR, DE, GB).",
        "pattern": "^[A-Za-z]{2}$"
      },
      "query": {
        "type": "string",
        "description": "Free-text query (legal name or identifier)."
      }
    }
  },
  "annotations": {
    "readOnlyHint": true
  }
}
Showing search_companies

Findings

WebMCP use

67 / 100 · weight 50
passTools registered
4 / 4
2 tools registered across 1 page.
failReal-browser eligible
0 / 8
The page's code registers these tools, but a real visitor's browser does not get them yet: WebMCP needs a native modelContext or a current origin trial token, and this page has neither.
passRegistration timing
4 / 4
Every measured tool registered within 785.5ms of navigation.
toolbook_demo
failCanonical entry point
0 / 4
Every tool registers through the deprecated navigator.modelContext alias; move them to document.modelContext before the alias is removed.
toolsearch_companies
fix
// Use the canonical entry point - navigator.modelContext is deprecated.
document.modelContext.provideContext({ tools: [/* ... */] });
passSchema validity
5 / 5
All 2 tools declare a structurally valid object input schema.
passSchema quality
4 / 4
All 2 tool schemas describe their parameters and stay within Chrome's size guidance.
passStub detection
5 / 5
All 2 tools declare an execute handler.
warningAnnotations present
2 / 4
1 of 2 tools declare no readOnlyHint, so an agent cannot tell a read from a write without guessing from the name.
toolbook_demo
book_demo
fix
{
  name: "book_demo",
  annotations: { readOnlyHint: true, destructiveHint: false, idempotentHint: true }
}
passAnnotation mismatch
3 / 3
No tool claims to be read-only while its name says it writes (1 declared hint checked).
not applicableUntrusted content hint
0 / 2
No tool's contract suggests it returns text written by somebody other than the site, so there is nothing to flag as untrusted.
passRegistration errors
2 / 2
No tool registration threw during the capture.
warningToolchange coherence
1 / 2
2 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"));
not applicableInjection surface
0 / 3
The injection-surface model hop returned no usable result, so tool contracts were not reviewed for injection surface.

Usefulness

100 / 100 · weight 30
passNaming quality
2 / 2
All 2 tool names are consistent, verb-led, and within Chrome's size guidance.
not applicableDescription quality
0 / 6
The description-quality model hop returned no usable result, so descriptions were not rated.
not applicableTool selection
0 / 14
The tool-selection model hop returned no usable result.
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

0 / 100 · weight 20
warningHuman parity
0 / 8
2 of 2 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.
toolsearch_companies
search_companies, book_demo
fix
<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="search_companies" tooldescription="...">
  <!-- the same action, as UI -->
</form>
not applicablePage experience
0 / 12
The page-experience model hop returned no usable result, so the page was not graded.

Tool selection

The tool-selection model hop returned no usable result.
how this was captured
chrome
148.0.7778.96
capture shim
v1
spec snapshot
2026-08
mode
fast
pages
1
tools
2
run time
5s
finished
Aug 28, 2026