pyrra.net WebMCP audit

Name: pyrra.net WebMCP audit
Creator: ora

Rescan

audited Aug 28, 2026in 4s

66/ 100

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

WebMCP use96

Usefulness60

Human experience0

about:blank

No agent run recorded yet.

No steps recorded

Tools

list-blog-posts

List all writing published on pyrra.net — nonprofit website guides plus the clearly separated engineering and security notes in Felix’ Lab. Returns title, URL, publication date, category and summary as JSON.Answers a question. Declared read only.

pagehttps://www.pyrra.net/

implementation

viaimperative

entry pointdocument

registered after587ms

executepresent

api surfaceTakes no parameters.

annotations

read onlytrue

destructivenot declared

idempotentnot declared

open worldnot declared

untrusted contentnot declared

titlenot declared

2 findings

warningUntrusted content hint

1 / 2

1 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.

list-blog-posts: post, note

fix

{ name: "list-blog-posts", annotations: { untrustedContentHint: true } }

warningHuman parity

0 / 8

4 of 4 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.

list-blog-posts, get-blog-post, get-site-context, send-contact-message

fix

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

tool json

{
  "name": "list-blog-posts",
  "description": "List all writing published on pyrra.net — nonprofit website guides plus the clearly separated engineering and security notes in Felix’ Lab. Returns title, URL, publication date, category and summary as JSON.",
  "inputSchema": {
    "type": "object",
    "properties": {},
    "additionalProperties": false
  },
  "annotations": {
    "readOnlyHint": true
  }
}

Findings

WebMCP use

96 / 100 · weight 50

passTools registered

4 / 4

4 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.

passRegistration timing

4 / 4

Every measured tool registered within 587.5999999046326ms of navigation.

toolget-site-context

passCanonical entry point

4 / 4

All 4 tools register on the canonical document.modelContext entry point.

passSchema validity

5 / 5

All 4 tools declare a structurally valid object input schema.

passSchema quality

4 / 4

All 4 tool schemas describe their parameters and stay within Chrome's size guidance.

passStub detection

5 / 5

All 4 tools declare an execute handler.

passAnnotations present

4 / 4

All 4 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 (4 declared hints checked).

warningUntrusted content hint

1 / 2

1 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.

toollist-blog-posts

list-blog-posts: post, note

fix

{ name: "list-blog-posts", annotations: { untrustedContentHint: true } }

passRegistration errors

2 / 2

No tool registration threw during the capture.

warningToolchange coherence

1 / 2

4 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

60 / 100 · weight 30

passNaming quality

2 / 2

All 4 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.

warningCoverage vs. site type

4 / 8

The tool set covers 2 of the 4 things an agent needs on a saas site; it cannot create a record or start a job or update or move an existing record.

Human experience

0 / 100 · weight 20

warningHuman parity

0 / 8

toollist-blog-posts

list-blog-posts, get-blog-post, get-site-context, send-contact-message

fix

<!-- Give the tool a visible counterpart: a declarative form is one the person can see and use too. -->
<form toolname="list-blog-posts" 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: 4
run time: 4s
finished: Aug 28, 2026