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

Annotations already declare read-only, idempotent, closed-world, and non-destructive behavior. The description adds useful context beyond that by specifying the return contents (definition, worked example, related terms), glossary breadth, and one-term-per-call constraint; it does not address unknown-term behavior or matching rules.

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 front-loads purpose, then gives usage context, then states the call constraint in three sentences. The example list is dense but relevant to retrieval, with no filler or repetitive wording.

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 simple, one-parameter, read-only glossary lookup, the description covers purpose, trigger conditions, return contents, and call cardinality. Although there is no output schema, the description explains what is returned, so remaining details such as miss behavior are minor.

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 term parameter already documents accepted input and examples. The description reinforces 'one term per call' and lists more examples, but adds little syntax or constraint beyond what the schema already provides.

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 verb and resource: it returns a plain-language definition, worked example, and related terms for an insurance or medical-billing term from KeepMD's glossary. The scope is clear, but it does not explicitly distinguish itself from siblings such as lookup_codes or search_codes.

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?

It gives an explicit trigger: use when a user asks what a word, column, or abbreviation on an EOB, Medicare Summary Notice, or bill means. It also states 'Takes one term per call,' but offers no when-not guidance or named alternatives.

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