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

Annotations already establish readOnly, idempotent and openWorld semantics, so the bar is lower; the description adds real behavioral context by disclosing the heavy return payload and the max_authors/authorCount truncation behavior for large collaboration papers. It omits auth requirements and rate limits, so it is not fully rich.

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-loads the verb and identifier forms, and the trailing note about author capping is well placed. However, the long mid-sentence catalogue of returned fields is verbose and partly redundant given an output schema exists.

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 bounded two-parameter lookup with a full output schema and covering annotations, the description supplies everything an agent needs: what is fetched, from which identifiers, and how author lists are limited. No material gap remains.

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%, both parameters are fully documented there, so baseline 3 applies. The description's note that max_authors caps the list while authorCount holds the full count largely restates the schema wording rather than adding new meaning.

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 specific verb and resource ('Fetch one paper's full INSPIRE-HEP record') and enumerates the identifier forms accepted, which clearly separates it from the sibling search_literature tool that would be used to find papers rather than retrieve one.

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?

Gives clear context that this is a single-record lookup keyed on recid/arXiv ID/DOI, and enumerates the accepted identifier syntaxes in the schema. It never explicitly names an alternative (e.g. 'use search_literature when you only have a title') or states exclusions, so it stops short of a 5.

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