rcsb_get_polymer_entities

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, and the description adds valuable behavioral detail: unknown IDs are returned under 'not_found', and fields replaces a curated default. This goes beyond the safety flags, though it does not disclose auth or rate limits.

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 description is tightly structured: a one-line purpose, a default-fields line, and a compact Args list. There is no redundant text; every sentence adds informational value.

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?

With an output schema present and strong annotations, the description still covers default fields, field customization, unknown-ID behavior, and related tool integration. It is comprehensive for a read-only retrieval tool.

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 compensate. It thoroughly explains entity_ids with format, example, and provenance from rcsb_search_by_sequence, and fields with an example and a discovery path via rcsb_describe_data_object. Both parameters receive meaningful semantics beyond the bare schema.

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 clearly states 'Fetch polymer entities (protein/nucleic-acid molecules)' with a specific verb and resource. This distinguishes it from sibling tools like rcsb_get_nonpolymer_entities and rcsb_get_branched_entities.

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 implies a clear usage context by noting that entity_ids are 'exactly what rcsb_search_by_sequence returns', linking it to a sequence search workflow. It does not explicitly name alternative tools or exclusions, but the polymer-specific scope and the reference to related tools provide sufficient guidance.

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