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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety needs no restating. The description adds value beyond them by disclosing the unknown-id failure mode (error with nearest matches) and enumerating the returned fields. It stops short of explaining what ambiguous fields like probe or adoption contain, so it is strong but not exhaustive.

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?

Three tight sentences: purpose first, return/error contract second, routing last. No filler and the most decision-relevant information is front-loaded.

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 carries the return-value burden and does so by listing the field set and the error behavior, which is enough to call it correctly. Minor gap: several field names are opaque and there is no note on record size or truncation.

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% and the id parameter already documents the accepted forms with examples (mcp, ard, llms.txt, RFC 9421). The description's mention of id/acronym/filename/RFC restates the schema rather than adding resolution rules or precedence when a value matches multiple standards, so baseline 3 applies.

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 and resource ("Fetch one standard's complete specification record") plus the accepted identifier forms, and explicitly names the sibling tools it is not (search, define). An agent can distinguish it from every sibling without opening a schema.

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 explicit routing: use get when the id is known, use search to discover unknown ids, use define for glossary concepts. Both the when and the when-not are stated with the alternative named.

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