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

Annotations already cover read-only, idempotent, non-destructive and open-world traits, so the bar is lower; the description still adds real value by disclosing the hard 2 MB payload ceiling, the absence of JS rendering, and the shape of the rendered output. It omits failure behavior (timeouts, non-HTML content, HTTP error handling), which would matter for a network fetch.

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?

Two tight sentences: the first front-loads what the tool does and returns, the second carries the guardrail constraints. No filler, no restatement of the name or annotations.

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?

With no output schema, the description usefully characterizes the returned Markdown and the input limits, which is enough to call it correctly. It leaves out error/edge-case behavior such as non-HTML responses or fetch failures, a minor but real gap for a single-URL fetch tool.

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?

There is a single parameter with 100% schema description coverage, so the schema already explains that url must be a public http/https page URL. The description only echoes the 'public page' constraint without adding format or normalization detail, which is the expected baseline when the schema does the work.

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 description states a specific verb+resource+output: read one public HTML page and return clean Markdown, enumerating what is preserved (title, headings, lists, tables, absolute links). It is unambiguous about scope, though it never names or contrasts itself with page-adjacent siblings such as page_check, seo_check or get_transcript.

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?

It gives clear negative conditions for use: no logins, no paywalls, no JavaScript rendering, and a 2 MB HTML limit, which lets an agent rule this tool out for authenticated or client-rendered pages. It stops short of naming an alternative tool for those cases, so exclusions are stated without a redirect.

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