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

With no annotations provided, the description carries the burden of disclosing behavior. It mentions 'via Crossref' (external API) and lists return fields (metadata, citations, journal), but does not disclose potential rate limits, error handling, or whether it is read-only. This is moderate transparency for a simple lookup.

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 a single, front-loaded sentence that immediately states the tool's action and resource. Every word contributes value, with no redundancy or fluff.

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 single-parameter, no-output-schema tool, the description covers the core purpose and expected outputs (metadata, citations, journal). It does not address edge cases like invalid DOIs or API errors, but the simplicity of the tool makes the description sufficiently complete.

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?

The schema covers 100% of the parameter 'doi' with an example format. The description adds no extra semantic detail beyond reinforcing that it looks up by DOI, so it does not exceed the baseline set by high schema coverage.

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 uses the specific verb 'Look up' and clearly identifies the resource (paper by DOI via Crossref) and the expected outputs (metadata, citations, journal). It distinguishes itself from siblings like arxiv_search or author_papers by targeting DOI-based lookup.

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?

The description provides clear context: use when you have a DOI and want paper details. It does not explicitly mention alternatives or when not to use, but the context is unambiguous for a DOI lookup tool, so it meets the 'clear context, no exclusions' criterion.

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