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read_form

List a form's fields with names, types, labels, and options to address them before filling. Check usability and include hidden controls outside the form.

Instructions

List a form's fields with their names, types, labels and options.

read_page returns rendered text, which loses everything needed to address a field: a large form arrives as labels with no name, and a <select>'s options vanish. Use this before filling a form you have not seen. root is a CSS selector for the form (default: the first form on the page). Hidden inputs are counted, not listed.

Set whole_page=true for controls a page attached outside the form — a picker or editor dialog is often appended to the body, and a field found there is still one the form will post.

Each field carries usable: false means it is in the DOM but hidden or disabled right now, so choosing it will fail. A form hides sections it has not revealed yet — measured on KVR, a news form keeps event_country hidden until the Deal/Offer type is chosen. Check usable before addressing a field rather than discovering it through a timeout.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "read_form"
  }
}

Input Schema

Name	Required	Default
`root`	No	form
`max_fields`	No
`whole_page`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 3, 2026

TDQS

A4.7/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full behavioral burden and does so well: hidden inputs are counted not listed, each field carries a `usable` flag whose false value predicts failure, and forms can hide unrevealed sections (illustrated with the event_country example). This is exactly the kind of runtime behavior an agent needs and cannot get from the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the core purpose, then layers the read_page contrast and the usable/hidden-section guidance in a logical order. It is somewhat verbose, with the KVR anecdote and 'rather than discovering it through a timeout' phrasing adding length beyond the minimum needed.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained, and the description still covers field shape (name/type/label/options), the usable flag, and whole_page scope. The only real gap is the undocumented max_fields parameter, which matters for very large forms.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. It explains `root` (CSS selector, default first form) and `whole_page` (controls appended outside the form, e.g. a picker dialog) thoroughly, but `max_fields` is never mentioned in the description or the schema, leaving one of three parameters undocumented.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('List a form's fields') and enumerates exactly what is returned: names, types, labels and options. It explicitly contrasts itself with the sibling read_page, explaining what read_page loses (name attributes, select options), so an agent can pick the right tool without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit trigger ('Use this before filling a form you have not seen') and names the alternative read_page with the reason to prefer this one. The whole_page guidance also tells the agent when that mode is needed. Nothing about selection is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.