check_accessibility_markup

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so the safety profile is covered. The description adds the useful nuance that it works on *source* signals (static markup rather than rendered output) and mentions empty controls, but says nothing about output shape or how findings are reported.

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

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

One front-loaded sentence with no filler, and the six signal categories are packed into a compact list. It reads slightly like a keyword dump, but nothing is wasted.

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

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

For a read-only, single-parameter analyzer with no output schema, the description gives an adequate inventory of what is inspected but omits input expectations (raw HTML string, size limit) and any hint of what the result contains. Adequate but with clear gaps.

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

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

Schema description coverage is 0% and the single parameter (html, max 120000 chars) is undocumented in both schema and description. The description never clarifies that the input is raw HTML to analyze, nor any format/length expectations, so it fails to compensate for the coverage gap.

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

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

The verb+resource is clear once the enumeration is read: it finds accessibility-relevant markup signals (language, title, headings, alt text, labels, empty controls) in HTML source. It is specific about what it looks for, but never differentiates itself from sibling tools such as check_motion_accessibility or inspect_html.

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

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

There is no statement of when to reach for this tool versus the many sibling checks (check_motion_accessibility, analyze_contrast, inspect_html). No prerequisites, no exclusions, no scope guidance beyond the list of signals.

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