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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds valuable behavioral context by explaining the internal process ('Fetches the page, extracts title/description/key links') and the output format ('standard llms.txt markdown format', 'single text blob'). This goes beyond the annotations, even though it does not cover every possible edge case.

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 description is only three sentences, with the core action and purpose stated first. Every sentence adds value, and the 'Useful for' list is compact. No redundancy or filler content.

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?

The tool is simple (2 params, no output schema), yet the description explains the input, process, output format, and use cases. It even mentions where to place the output ('site-root/llms.txt'). This is sufficient for an agent to invoke it confidently, though it omits potential issues like site fetch failures or rate limiting.

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 100%, so the input schema already documents both parameters (url and max_links) with descriptions. The description does not add parameter-specific semantics beyond restating the output format, but the schema carries the heavy lifting, making the baseline 3 appropriate.

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 clearly states the specific action ('Generate a production-ready llms.txt file'), the resource (any URL), and the outcome (AI crawlers can index the site). It distinguishes itself from sibling tools by focusing on generating llms.txt, which none of the siblings appear to do.

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 provides explicit use cases ('Useful for: getting a client's site indexed by AI, drafting llms.txt for your own project, or auditing how an AI crawler would see a competitor'). However, it does not mention when to avoid this tool or suggest alternatives, so it falls short of a full 5.

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