hopi.co.uk WebMCP audit

audited Aug 28, 2026in 4s
53/ 100

2 tools registered. Strongest in WebMCP use, weakest in human experience.

WebMCP use76
Usefulness50
Human experience0
about:blank

No agent run recorded yet.

No steps recorded

Tools

/
hopi_directory: warning

hopi_directory

List all of Hopi's agent-callable tools (name, page URL, category, description). Call this first to discover the catalogue, then open a tool's url and invoke the tool named there.Answers a question. Declared read only.
pagehttps://hopi.co.uk/
implementation
viaimperative
entry pointdocument
registered after137ms
executepresent
api surface
categoryoptional
annotations
read onlytrue
destructivenot declared
idempotentnot declared
open worldnot declared
untrusted contentnot declared
titlenot declared
3 findings
warningSchema quality
2 / 4
1 of 2 tool schemas are harder for an agent to use than they need to be: hopi_directory declares no required list, so an agent cannot tell which parameters are mandatory.
hopi_directory: declares no required list, so an agent cannot tell which parameters are mandatory
fix
{
  name: "hopi_directory",
  inputSchema: {
    type: "object",
    properties: {
      query: { type: "string", description: "What to search for" }
    },
    required: ["query"]
  }
}
warningNaming quality
1 / 2
Tool naming makes selection harder than it needs to be: 2 names do not start with a verb (hopi_directory).
fix
{ name: "hopi_directory" /* short, unique, verb-based */ }
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.
hopi_directory, hopi_search
fix
<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="hopi_directory" tooldescription="...">
  <!-- the same action, as UI -->
</form>
tool json
{
  "name": "hopi_directory",
  "description": "List all of Hopi's agent-callable tools (name, page URL, category, description). Call this first to discover the catalogue, then open a tool's url and invoke the tool named there.",
  "inputSchema": {
    "type": "object",
    "properties": {
      "category": {
        "type": "string",
        "description": "Optional category filter, e.g. money, maths, convert, text, health"
      }
    }
  },
  "annotations": {
    "readOnlyHint": true
  }
}
Showing hopi_directory

Findings

WebMCP use

76 / 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 137.29999995231628ms of navigation.
toolhopi_search
passCanonical entry point
4 / 4
All 2 tools register on the canonical document.modelContext entry point.
passSchema validity
5 / 5
All 2 tools declare a structurally valid object input schema.
warningSchema quality
2 / 4
1 of 2 tool schemas are harder for an agent to use than they need to be: hopi_directory declares no required list, so an agent cannot tell which parameters are mandatory.
toolhopi_directory
hopi_directory: declares no required list, so an agent cannot tell which parameters are mandatory
fix
{
  name: "hopi_directory",
  inputSchema: {
    type: "object",
    properties: {
      query: { type: "string", description: "What to search for" }
    },
    required: ["query"]
  }
}
passStub detection
5 / 5
All 2 tools declare an execute handler.
passAnnotations present
4 / 4
All 2 tools declare a readOnlyHint, so an agent knows which calls change state.
passAnnotation mismatch
3 / 3
No tool claims to be read-only while its name says it writes (2 declared hints 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

50 / 100 · weight 30
warningNaming quality
1 / 2
Tool naming makes selection harder than it needs to be: 2 names do not start with a verb (hopi_directory).
toolhopi_directory
fix
{ name: "hopi_directory" /* short, unique, verb-based */ }
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.
toolhopi_directory
hopi_directory, hopi_search
fix
<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="hopi_directory" 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
4s
finished
Aug 28, 2026