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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description adds real behavioral context beyond that: plural inputs are tolerated, the return includes related protocol ids, and standards names return a summary instead of an error rather than failing.

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, front-loaded with the core action, then input format, then the non-obvious edge-case behavior. No filler and every sentence adds information.

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?

There is no output schema, so the description takes on the burden and delivers: it names what is returned (the definition and related protocol ids) and describes the alternate return for standards. For a single-parameter read tool this is fully adequate.

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 0% and there is a single parameter, so the description must carry the load. It does meaningfully: it specifies that 'term' accepts an id, name, or alias, and that plurals are tolerated — details absent from the schema (which only gives type and length bounds).

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 ('Define') and resource ('a glossary term of the agentic web'), and the special-case behavior for standards makes the scope unambiguous. An agent can distinguish this from siblings like get, search, or ask 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?

The description implies when this tool applies (looking up a term's definition) and clarifies that standards names are handled gracefully, but never explicitly contrasts it with sibling lookup tools such as get, search, or ask. Usage is left to inference.

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