get_fulltext

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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds meaningful behavior: the failure mode (`available: false` plus an open-access link) and a prompt-injection warning about third-party content. It omits truncation behavior around max_chars and any rate-limit or coverage caveats.

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 primary behavior followed by the fallback and the safety note. No filler, though the layout with the fallback as a separate paragraph is slightly fragmented.

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-value explanation isn't strictly required (and the description helpfully adds the failure shape anyway). The major completeness gap is identifier format guidance, which an agent needs in order to call this correctly given 0% schema coverage.

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 0%, so the description must carry parameter meaning, but it never explains what `identifier` accepts (PMID? PMCID? DOI?) — a critical ambiguity for a PMC-specific tool. `max_chars` is likewise unmentioned, leaving both parameters undocumented.

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 ('Open-access full text as plain text') plus the scope condition ('when PubMed Central has it'). It clearly differs from metadata-oriented siblings like get_paper_details, though it does not name any sibling explicitly.

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 only implied: an agent can infer this is for when full text (not just metadata) is needed. There is no explicit guidance on when to prefer it over get_paper_details or search_literature, and no stated prerequisites for the identifier.

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