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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, covering safety and idempotency. The description adds behavioral context by stating it returns normalized metadata and facets, but does not disclose pagination limits or other operational details. Since annotations cover the core behavioral traits, the description's added value is moderate, warranting a 3.

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, well-structured paragraph that front-loads the primary purpose and then details filters and return content. It is concise at roughly three sentences, though the final sentence about repository coverage is somewhat redundant with the earlier mention of 3,500+ repositories. Overall, it is efficient and earns a high score.

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?

With 8 parameters and an output schema present, the description covers the main functionality: search scope, filters, return metadata, and facets. It does not explicitly mention pagination, but the schema includes page and limit parameters, and the output schema covers return format. The description is sufficiently complete for an agent to use the tool correctly, with minor gaps around pagination behavior.

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%, so each parameter already has a clear description. The tool description repeats the filter options (keyword, resource type, year, repository, funder) but does not add significant new meaning beyond what the schema provides. The mention of specific repositories (Zenodo, Figshare) adds minor illustrative value. Per guidelines, baseline is 3, and the description meets but does not exceed that.

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 searches DataCite-registered DOIs for research outputs, enumerating specific resource types and filters. The verb 'search' and resource 'DataCite-registered DOIs' are precise, and it implicitly differentiates from siblings like datacite.doi.lookup (which likely fetches a single DOI) by focusing on search and broad coverage.

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 clearly indicates when to use this tool: to search for DOIs across DataCite. It lists filters and coverage, making the use case unambiguous. However, it does not explicitly mention alternatives or when not to use it, though the context of siblings like datacite.client.search suggests it's for DOI search, not client search. The guidance is strong but lacks explicit exclusions.

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