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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds behavioral detail beyond them: the invalid-input path returns an error that lists allowed terms and does not return definitions, and blank strings are treated as whole-set lookups. That error/edge-case disclosure is the valuable part.

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?

Four tight sentences, front-loaded with the purpose, then the allowed-value domain, then the two edge-case branches, then the sibling routing. Nothing is padded or buried; the term list is the only mild duplication of the schema.

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 one-optional-parameter, read-only lookup with no output schema, the description covers input domain, defaults, and error behavior adequately. The only gap is a rough sense of the returned shape (one definition text versus an all-definitions payload), which is minor given there is no output schema to lean on.

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 schema property already documents the allowed values, omission, empty string, and unknown-term error. The description only marginally exceeds this by adding 'blank' (whitespace) handling and stating that the error path withholds definitions, so the 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?

The description names the exact resource (a Crovia term definition) and enumerates the closed set of allowed terms, so an agent knows precisely what comes back. It also distinguishes itself from sibling crovia_vs_causari by name and purpose, which is the key disambiguation in this toolset.

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?

Explicit when-to-use (look up a single term), explicit fallback (omit the term or pass empty/blank to get every definition), explicit failure mode (any other value errors out), and explicit alternative routing (use crovia_vs_causari for product comparison). All conditions are stated rather than inferred.

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