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 genuine behavioral context beyond that: the cost model (free within a daily allowance, then $0.003 USDC per call via x402), which is material for an agent deciding whether to call it. It stops short of describing result limits or pagination.

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 tight sentences, front-loaded with purpose and followed by the cost constraint. No filler or repetition of the tool name.

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 values need not be explained, and the description confirms the shape of results. Combined with the pricing note, an agent has enough to call it, though limits on result volume and the daily allowance size are unstated.

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 a single parameter with 100% schema coverage, so the schema already documents it. The description adds nothing about query syntax, supported operators, or field targeting, which is the baseline-worthy 3 given high 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 states a specific verb and resource ("full-text search of scholarly works") and even previews what results contain (citations, authors, open-access links). It does not, however, differentiate itself from sibling work-retrieval tools such as scholarly__work or scholarly__citing-works, 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?

Usage is implied by the phrasing (search when you want papers by keyword), and the description adds a practical constraint about the free daily allowance and per-call pricing. There is no explicit statement of when to prefer this over scholarly__work or the crossref/pubmed/arxiv search siblings.

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