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

Annotations already cover read-only/idempotent/non-destructive, but the description adds substantial context they don't: the upstream sources queried (Crossref, DOI system, OpenAlex), the batch cap of 10, the three verdict values and their meaning, and retraction-status retrieval. This is well beyond the structured hints.

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?

Front-loaded with the invocation triggers, then mechanics, then verdict semantics, then the scope caveat. Every sentence carries information; the only mild redundancy is the batch-size note already in 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?

Given an output schema exists, return-value documentation is optional, yet the description usefully previews the verdict and retraction fields anyway. Combined with the source list, batch limit, and scope disclaimer, nothing an agent needs to invoke this correctly is missing.

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%, so the baseline is 3. The description's parameter guidance ('pass each reference as one string as written… up to 10') largely restates what the schema property description and maxItems already say, adding only the enumeration of fields (authors, year, title, journal, DOI).

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 concrete verb+resource ('check references and DOIs') and immediately scopes it ('bibliographic details only, not whether a paper's claims are true'). The title and description together leave no ambiguity about what is checked, and none of the siblings (feedback/indexing tools) do anything similar.

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?

Opens with explicit trigger phrases ('are these references real?', 'check my bibliography', 'is this DOI correct?', 'has this paper been retracted?'), which is precisely the when-to-use signal an agent needs. It also states a when-not boundary by clarifying it does not assess claim truth.

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