timmcmahon.com.au WebMCP audit

Name: timmcmahon.com.au WebMCP audit
Creator: ora

Rescan

audited Aug 28, 2026in 4s

50/ 100

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

WebMCP use69

Usefulness50

Human experience0

about:blank

No agent run recorded yet.

No steps recorded

Tools

scan_images_c2pa

Scan every <img> on the current page for C2PA Content Credentials (content provenance metadata) and return a per-image summary: whether a manifest is present, the claim generator (the tool that produced or edited the image), the title, and the signer name. Use this to find which images on a page carry provenance data. Note: provenance is decoded but NOT cryptographically verified.Takes an action on the site.

pagehttps://timmcmahon.com.au/

implementation

viaimperative

entry pointdocument

registered after293ms

executepresent

api surface

limitoptional

annotations

read onlynot declared

destructivenot declared

idempotentnot declared

open worldnot declared

untrusted contentnot declared

titlenot declared

3 findings

warningNaming quality

1 / 2

Tool naming makes selection harder than it needs to be: 2 names do not start with a verb (scan_images_c2pa).

fix

{ name: "scan_images_c2pa" /* short, unique, verb-based */ }

failAnnotations present

0 / 4

2 of 2 tools declare no readOnlyHint, so an agent cannot tell a read from a write without guessing from the name.

scan_images_c2pa, inspect_image_c2pa

fix

{
  name: "scan_images_c2pa",
  annotations: { readOnlyHint: true, destructiveHint: false, idempotentHint: true }
}

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.

scan_images_c2pa, inspect_image_c2pa

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="scan_images_c2pa" tooldescription="...">
  <!-- the same action, as UI -->
</form>

tool json

{
  "name": "scan_images_c2pa",
  "description": "Scan every <img> on the current page for C2PA Content Credentials (content provenance metadata) and return a per-image summary: whether a manifest is present, the claim generator (the tool that produced or edited the image), the title, and the signer name. Use this to find which images on a page carry provenance data. Note: provenance is decoded but NOT cryptographically verified.",
  "inputSchema": {
    "type": "object",
    "properties": {
      "limit": {
        "type": "integer",
        "minimum": 1,
        "maximum": 100,
        "default": 25,
        "description": "Maximum number of images to fetch and scan (default 25, max 100)."
      }
    },
    "required": []
  },
  "annotations": {}
}

Findings

WebMCP use

69 / 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 293.89999985694885ms of navigation.

toolinspect_image_c2pa

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.

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.

failAnnotations present

0 / 4

2 of 2 tools declare no readOnlyHint, so an agent cannot tell a read from a write without guessing from the name.

toolscan_images_c2pa

scan_images_c2pa, inspect_image_c2pa

fix

{
  name: "scan_images_c2pa",
  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.

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 (scan_images_c2pa).

toolscan_images_c2pa

fix

{ name: "scan_images_c2pa" /* 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

toolscan_images_c2pa

scan_images_c2pa, inspect_image_c2pa

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="scan_images_c2pa" 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