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

Annotations already establish this is a read-only, idempotent operation; the description goes beyond them by describing exactly what the draft will contain: URLs grouped into H2 sections by path, titles from slugs, lastmod kept, TODO placeholders, and sitemap-index handling. This gives the agent concrete expectations about output behavior.

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?

The core behavior is front-loaded in a dense but informative first sentence, with a useful edge-case note and an example. No filler is present, though the opening sentence packs several clauses together, making it slightly harder to parse.

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 does a good job of describing what the drafted llms.txt will contain and how sitemap indexes are treated. It does not explicitly specify the output MIME type or exact markdown formatting, but 'draft llms.txt' adequately implies the result for an agent.

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 coverage is 100%, so the schema already documents all four parameters and their defaults. The description adds no significant parameter-level meaning beyond the schema; the example in the description even mirrors the schema example.

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 action: paste a sitemap or URL list and get a draft llms.txt with documented transformations (H2 grouping by path, slug-derived titles, lastmod preservation, TODO placeholders). This distinguishes it clearly from sibling tools like validate_llms_txt or explain_document.

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?

The description gives clear input conditions ('Paste sitemap.xml, or one URL per line') and intended output ('get a draft llms.txt'), so an agent can infer when to use it. It does not explicitly name alternative tools or say when not to use it, but the sibling tools are distinct enough that confusion is unlikely.

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