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

Annotations already declare read-only, open-world, idempotent, and non-destructive behavior. The description adds useful behavioral context by noting it is a fast version and that it does not return the citing DOIs, which is beyond what annotations provide.

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 is concise and effective: it opens with user-friendly query examples, then a crisp definition, then a tradeoff relative to `citations`. Every sentence adds value with no filler.

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?

Given the tool has one simple parameter, a rich annotation set, and an output schema, the description fully covers purpose, scope, and relationship to a sibling. No significant information is missing for an agent to select and invoke the tool correctly.

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?

There is only one parameter, `doi`, and the schema gives only an example. The description compensates for the 0% schema description coverage by explaining that the DOI identifies the paper and that the tool returns its citation count.

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 clearly states the tool returns the incoming citation count for a DOI, with natural-language examples. It distinguishes itself from the sibling `citations` tool as a fast version when only the number is needed, not the citing DOIs.

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?

Explicitly says to use this tool when you only need the citation count, and points to `citations` as the alternative when citing DOIs are also required. This gives clear when-to-use and when-not-to-use guidance relative to a closely related sibling.

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