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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered. The description adds genuinely new behavioral context: metadata provenance ('the API that resolved the identifier') and the failure contract ('if no source returns a record, say so. Do not guess the abstract'), which is exactly the kind of anti-hallucination instruction an agent needs.

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 short sentences, front-loaded with the operation and its inputs; each sentence carries distinct information (what it returns, identifier types, provenance, failure handling). Slightly padded by listing the fields, which the output schema already provides.

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?

An output schema exists, so return-value explanation is not strictly required, and annotations cover safety. The description fills the remaining critical gap — what to do when resolution fails — making it essentially complete for a single-identifier lookup tool.

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 one parameter with 100% schema description coverage, and the description only restates the identifier vocabulary already documented in the schema. It adds no syntax, precedence, or format guidance (e.g. how to disambiguate an ambiguous bare string), so the baseline of 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?

Specific verb ('Fetch') plus a single, clearly bounded resource ('one paper'), and it enumerates the returned fields (title, authors, year, venue, abstract) and the accepted identifier types. It is unmistakably narrower than search_papers or find_related_papers, but it never names a sibling to make the contrast explicit.

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?

Usage is implied by the accepted identifier types — you call it when you already have a DOI/PMID/arXiv/OpenAlex id — but the description never states when to prefer this over search_papers or find_related_papers, nor any prerequisite or exclusion.

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