hiro.is WebMCP audit

Name: hiro.is WebMCP audit
Creator: ora

Rescan

audited Aug 28, 2026in 5s

43/ 100

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

WebMCP use62

Usefulness40

Human experience0

about:blank

No agent run recorded yet.

No steps recorded

capture followed a redirecthiro.is redirected to hirosecure.com. Everything below was served there.

Tools

get_hiro_overview

Return a short overview of Hiro: what it does, which security pillars it covers, and how to contact the team.Answers a question. Declared read only.

pagehttps://hirosecure.com/

implementation

viaimperative

entry pointnavigator

registered after360ms

executepresent

api surfaceTakes no parameters.

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.

get_hiro_overview, book_hiro_demo

fix

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

tool json

{
  "name": "get_hiro_overview",
  "description": "Return a short overview of Hiro: what it does, which security pillars it covers, and how to contact the team.",
  "inputSchema": {
    "type": "object",
    "properties": {},
    "additionalProperties": false
  },
  "annotations": {
    "readOnlyHint": true
  }
}

Findings

WebMCP use

62 / 100 · weight 50

warningTools registered

2 / 4

https://hiro.is/ redirected off its own domain to https://hirosecure.com/, so what follows describes the page that answered, not necessarily the site that was audited. 2 tools registered across 1 page.

https://hiro.is/ -> https://hirosecure.com/

fix

document.modelContext.provideContext({
  tools: [{ name: "your_tool_name", description: "...", inputSchema: { type: "object", properties: {} }, execute: async (args) => { /* ... */ } }],
});

failReal-browser eligible

0 / 8

https://hiro.is/ redirected off its own domain to https://hirosecure.com/, so what follows describes the page that answered, not necessarily the site that was audited. 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 360ms of navigation.

toolbook_hiro_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.

toolget_hiro_overview

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_hiro_demo

book_hiro_demo

fix

{
  name: "book_hiro_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

40 / 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.

failCoverage vs. site type

2 / 8

The tool set covers 1 of the 4 things an agent needs on a saas site; it cannot search or browse the catalog or create a record or start a job or update or move an existing record.

Human experience

0 / 100 · weight 20

warningHuman parity

0 / 8

toolget_hiro_overview

get_hiro_overview, book_hiro_demo

fix

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