get_polymer_entity

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

With no annotations, the description carries the behavioral disclosure burden. It clearly states the output is a JSON string and lists the returned fields, which implies a read-only operation. However, it does not mention error behavior, invalid PDB IDs, not-found cases, or any API/network dependencies.

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 well-structured with purpose, Args, and Returns sections, and the bullet list of return fields is useful. It is slightly verbose but contains no filler or redundant statements.

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?

The description covers the essential invocation details: parameter formats, default value, and return content. Since an output schema exists, the explicit return list is a bonus. It does not address edge cases or failure modes, but they are not critical for basic correct use.

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%, but the description fully compensates by explaining pdb_id's 4-character format with an example and entity_id's role with its default value. Both parameters receive meaningful semantic context 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 uses a specific verb and resource: 'Get information about a polymer entity (protein, DNA, RNA) within a PDB entry.' This clearly distinguishes the tool from entry-level, download, query, and search siblings, even though it does not name them 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?

The description implies the tool is for retrieving polymer entity details, but it provides no explicit guidance about when to choose it over siblings like get_pdb_entry or query_rcsb_api. No exclusions or alternative routing are given.

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