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

Annotations already cover the read-only and open-world profile, and the description adds genuinely non-obvious behavior: two NCBI round trips (latency/cost implication), an attribution requirement, and a per-successful-call price with the explicit note that failed calls are not charged. It stops short of noting rate limits or NCBI throttling.

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 core capability and output fields are front-loaded in the first sentence, followed by operational facts (request count, attribution, price). It is dense and slightly run-on but almost every clause carries information an agent needs.

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 three-parameter read tool with a full output schema, the description covers what it searches, what it returns, cost, and billing failure semantics. Remaining gaps (rate limits, result ordering, pagination) are minor.

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 all three parameters are already documented ('Search words', 'First publication year, e.g. 2020', '1 to 20 (default 10)'). The description only restates the optional year, adding no query syntax, boolean, or field-tag guidance beyond the schema.

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 ('PubMed articles matching words, optionally from a year') and even enumerates the returned fields (PMID, title, authors, journal, date, DOI, link). It never distinguishes itself from overlapping siblings such as research_papers, arxiv, doi, or clinical_trials, so an agent must infer the boundary.

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 gives no when-to-use or when-not-to-use guidance and names no alternative. With siblings like arxiv, research_papers, clinical_trials, and doi in the catalog, the agent gets no help deciding which literature source to pick.

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