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

With no annotations, the description carries the full burden: it does disclose the return shape ('matching passages or a notice when full text is unavailable'), which is genuinely useful failure-mode context. However, it says nothing about read-only safety, whether the retrieval is question-scoped ranking, or any limits beyond `k`; acceptable but not rich for an annotation-free tool.

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?

Three short sentences, front-loaded with the core action, followed by the availability constraint and the return behavior. Slight redundancy between the second sentence and the schema's `k` description, but no 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?

A three-parameter retrieval tool with no output schema and no annotations; the description covers what it does, the key availability limitation, and the shape of the response including the failure case. It only lacks guidance on fallback behavior when full text is unavailable (e.g., pointing to inspect_paper).

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 67%: `paperId` and `k` are already well documented in the schema (including the default of 4), and the description largely repeats the `k` behavior. It does add the meaningful constraint that `paperId` only resolves for indexed papers, and it implies the semantics of the undocumented `question` parameter (relevance query), but does not define how matching works.

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 — retrieve in-body passages from one paper for a specific question — which is meaningfully distinct from sibling tools like firecrawl_research_inspect_paper and firecrawl_research_search_papers. It does not name or route against those siblings explicitly, so it stops just short of full differentiation.

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 a useful precondition (full text only for indexed papers) but never says when to choose this over firecrawl_research_inspect_paper (metadata) or firecrawl_research_search_papers (discovery). Usage is implied by the phrase 'relevant to a specific question' rather than stated as guidance.

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