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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is established. The description adds the batch limit (~200 IDs), a cost hint, and the source context ('from search_pubmed'), enriching behavioral understanding without contradicting the annotations.

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?

Two concise sentences cover purpose, usage, batch details, and an alternative. Every clause adds value, with the most important information front-loaded.

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 simple one-parameter tool with comprehensive annotations and an output schema, this description is complete. It covers what the tool does, when to use it, how to batch, and what not to use it for (abstracts).

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 already provides 100% coverage by describing 'ids' as a comma-separated string. The description adds context by mentioning the size limit (~200) and the recommendation to batch, and even connects it to search_pubmed, which helps the agent understand how to obtain valid IDs.

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 starts with a specific verb 'Resolve' and the resource 'PubMed IDs' to 'citation metadata', enumerating the fields returned (title, authors, journal, publication date, DOI). It distinguishes itself from siblings by noting 'for the abstract text use get_abstract instead', making the tool's purpose unmistakable.

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?

It explicitly states when to use the tool ('Use when you have PMIDs and need the citation') and provides a direct alternative ('for the abstract text use get_abstract instead'). It also provides batching guidance ('Batch up to ~200 IDs per call') and a cost rationale ('much cheaper than calling per-ID'), which helps agents choose it efficiently.

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