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

With no annotations, the description carries the full burden and does so richly: it discloses the four lens algorithms (BM25 title/abstract match, citation classics, projected young-paper impact, last-two-years), curated-vs-OpenAlex corpus limits (up to 3 of every 10 results unmarked, source='openalex'), and auth/cost model (Personal+ required, $0.05 USDC via x402 in _meta). This is exactly the behavioral context an agent needs for a mutation-free read tool with no 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?

The priority instruction is front-loaded and most sentences are dense with substance (lens definitions, corpus caveats, payment). It is long and mixes return-value description, pricing and auth into one block, which slightly dilutes scanability, but there is little pure filler.

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?

There is no output schema, so the description must explain results and it does: lens composition, why/previous-citation info, per-paper DOI plus reason plus abstract, source='openalex' markers, and page size. Combined with the covered auth/cost and pagination details, an agent has everything needed to call and interpret it.

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 coverage is 80%, so the baseline is 3, and the description adds real value on top: it explains that q should carry key terms because 'filler words are ignored,' that paper is a DOI-or-title alternative to q, and what each lens enum means. It does not add much on page/page_size beyond the schema defaults, keeping it just under a 5.

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?

Opens with a specific imperative verb and resource: 'CALL THIS FIRST for a literature question about chemistry, materials or physics research.' It explicitly scopes the domain and contrasts with siblings like get_element_papers/get_subject_papers by centering on free-text literature questions rather than element/subject lookups. An agent can route without inspecting other schemas.

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?

States clear triggering conditions ('broad one' or 'specific process or parameter one') and prioritizes itself with 'CALL THIS FIRST.' It also guides pagination ('ask for page 2+ only if needed') and lens selection. It never explicitly names a sibling to prefer instead nor states when NOT to use it, so it falls short of 5.

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