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

Adds substantial behavior beyond the annotations: 10 MB size cap, private-address blocking, that failures are not charged, and that the response contains title, Markdown, links and character count. Annotations cover safety (readOnly/openWorld), and the description covers billing and failure semantics they do not.

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?

Front-loaded with the core transformation and format list, then limits, return fields, the alternative tool, and pricing. Every clause is informative, though the $0.005 price and trial status partially duplicate the title ('Markdown ($0.005)').

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?

Covers input types, size/scope limits, return contents, billing behavior and the sibling alternative. Since an output schema exists, return values need not be enumerated, yet the description does so anyway, leaving nothing essential missing for a one-parameter conversion 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?

Only one parameter and schema description coverage is 100%, so the schema already documents 'url' fully; baseline is 3. The description says 'any document URL' and lists accepted formats, which adds minor meaning but no syntax or format specifics beyond the schema.

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?

States a specific verb+resource ('turn any document URL into clean Markdown') and enumerates the exact input formats supported (web pages, PDFs, DOCX, XLSX/XLS, OpenDocument, CSV, XML, plain text). It also distinguishes itself from the sibling markdown-rendered by scoping JS-heavy sites elsewhere.

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?

Gives an explicit routing condition and alternative: 'For JavaScript-heavy sites use /markdown/rendered.' It also states a hard constraint (private addresses are blocked) and a 10 MB limit, so the agent knows when this tool applies and when it does not.

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