v-sum.com WebMCP audit

Name: v-sum.com WebMCP audit
Creator: ora

Rescan

audited Aug 28, 2026in 7s

42/ 100

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

WebMCP use55

Usefulness50

Human experience0

about:blank

No agent run recorded yet.

No steps recorded

Tools

open_llms_txt

Fetch V-Sum llms.txt (structured site summary for language models).Takes an action on the site.

pagehttps://v-sum.com/

implementation

viaimperative

entry pointprovideContext

registered after1203ms

executepresent

api surfaceTakes no parameters.

annotations

read onlynot declared

destructivenot declared

idempotentnot declared

open worldnot declared

untrusted contentnot declared

titlenot declared

4 findings

warningCanonical entry point

2 / 4

3 of 6 tools still register through the deprecated navigator.modelContext alias.

open_llms_txt, open_api_catalog, navigate_to_path

fix

// Use the canonical entry point - navigator.modelContext is deprecated.
document.modelContext.provideContext({ tools: [/* ... */] });

warningNaming quality

1 / 2

Tool naming makes selection harder than it needs to be: 6 names do not start with a verb (open_llms_txt).

fix

{ name: "open_llms_txt" /* 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.

open_llms_txt, open_api_catalog, navigate_to_path, open_llms_txt, open_api_catalog

fix

{
  name: "open_llms_txt",
  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.

open_llms_txt, open_api_catalog, navigate_to_path, open_llms_txt, open_api_catalog

fix

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

tool json

{
  "name": "open_llms_txt",
  "description": "Fetch V-Sum llms.txt (structured site summary for language models).",
  "inputSchema": {
    "type": "object",
    "properties": {},
    "additionalProperties": false
  },
  "annotations": {}
}

Findings

WebMCP use

55 / 100 · weight 50

passTools registered

4 / 4

6 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.

warningRegistration timing

2 / 4

The slowest tool took 1203ms to register, past the 1000ms an agent reading the registry at first paint would wait for.

toolopen_api_catalog

open_api_catalog: registered at 1203ms

fix

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

warningCanonical entry point

2 / 4

3 of 6 tools still register through the deprecated navigator.modelContext alias.

toolopen_llms_txt

open_llms_txt, open_api_catalog, navigate_to_path

fix

// Use the canonical entry point - navigator.modelContext is deprecated.
document.modelContext.provideContext({ tools: [/* ... */] });

passSchema validity

5 / 5

All 6 tools declare a structurally valid object input schema.

passSchema quality

4 / 4

All 6 tool schemas describe their parameters and stay within Chrome's size guidance.

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.

toolopen_llms_txt

open_llms_txt, open_api_catalog, navigate_to_path, open_llms_txt, open_api_catalog

fix

{
  name: "open_llms_txt",
  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.

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.

failRegistration errors

0 / 2

3 tool registrations threw during the capture, so the registry an agent reads is incomplete.

duplicate tool name registered: open_llms_txt

fix

try {
  document.modelContext.provideContext({ tools: [/* ... */] });
} catch (err) {
  console.error("WebMCP registration failed", err);
}

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"));

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: 6 names do not start with a verb (open_llms_txt).

toolopen_llms_txt

fix

{ name: "open_llms_txt" /* 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

toolopen_llms_txt

open_llms_txt, open_api_catalog, navigate_to_path, open_llms_txt, open_api_catalog

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="open_llms_txt" 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: 6
run time: 7s
finished: Aug 28, 2026