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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description earns credit for disclosing the return shape — a one-line definition and its page per term — which matters because there is no output schema, and for making clear the filter is optional ('all if left out' is mirrored in the schema).

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 opening sentence is well front-loaded and does real work. The second sentence is a verbatim duplication of the enum already present in the schema and consumes most of the description's length, which crowds out the more valuable missing content (when to use this versus the two siblings).

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?

For a zero-required-param, single-filter read tool with rich annotations and no output schema, the description covers scope and return content adequately. The only real gap is routing guidance against define_term and search_glossary, which is a modest rather than fatal omission.

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% and the single parameter is a fully enumerated enum, so the schema already does all the work. The description's second sentence simply re-lists the same 15 enum values, adding no meaning about defaults or behavior beyond what the schema shows.

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 first sentence names a specific resource (the glossary) and scope (all terms or one topic) and states what comes back (one-line definition plus page). It is clear what the tool does, though it never names or contrasts with search_glossary or define_term, so an agent must infer the boundary itself.

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?

Usage is only implied: 'Every term ... or in one topic' suggests browsing rather than targeted lookup, and the topic list hints at the taxonomy. It never says when to prefer this over search_glossary (keyword search) or define_term (single definition), which is the one decision an agent actually has to make.

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