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

With no annotations, the description carries the full behavioral burden, and it does disclose two meaningful traits: results are merged and de-duplicated across three sources, and each call costs $0.01 USDC via x402 on Base — a significant operational fact an agent must know before invoking. However, it says nothing about rate limits, payment failure behavior, or result-size/pagination behavior beyond what the schema implies.

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 sentences, front-loaded with what the tool does and followed by the pricing constraint — no filler. The return-field list is dense but earns its place because there is no output schema to describe the response shape.

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 7-parameter search tool with no output schema, the description covers the essentials: what is searched, how sources are combined, what each result contains, and the cost of a call. The only real gap is disambiguation from the singular/related-paper siblings, which matters given how similarly named they are.

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 seven parameters (q, sort, source, fromYear, toYear, maxItems, openAccess) are already documented in structured form, making the baseline 3 appropriate. The description adds only the implicit note that source can span all three providers, which is already implied by the schema's `all | openalex | arxiv | crossref` enumeration.

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 ("Search scholarly papers") and names the exact upstream sources (OpenAlex, arXiv, Crossref) plus the merge/de-duplicate behavior, which lets an agent infer it is the aggregate search rather than a single-paper lookup. It stops short of explicitly naming the research_paper and research_related_papers siblings, so differentiation is inferred from the name/description rather than stated.

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?

There is no when-to-use guidance, no exclusions, and no mention of the closely named siblings research_paper or research_related_papers. The agent must infer from the tool name and the source list that this is the multi-source keyword search entry point, but nothing in the text says so.

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