rcsb_get_entries

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

Beyond the readOnly/idempotent/openWorld annotations, the description discloses unknown-ID handling ('not_found'), the fact that fields replaces a curated default, and that component ids appear under a specific key. These are non-obvious behaviors not visible in the schema.

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 about 100 words but communicates purpose, usage, and parameter semantics in a structured way. Each paragraph earns its place, with 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?

The description covers input formatting, output behavior (component ids, not_found), and how to proceed with related tools. With an output schema present, this is a complete self-contained guide.

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 covers only names and types; the description adds the 4-character code format, one-element list convention, examples, and GraphQL selection guidance with a discoverability pointer. This fully compensates for 0% schema coverage.

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 opens with 'Fetch metadata for one or more PDB entries' explicitly naming the verb, resource, and scope. It lists specific fields (title, method, resolution, size, dates, citation) and distinguishes itself from sibling rcsb_get_* tools by explaining how to drill from entry ids to entity/assembly ids.

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?

It gives explicit compose-to-call instructions for sibling tools ('polymer_entity_ids... -> "<ENTRY>_N"') and tells when to use the result with rcsb_describe_data_object to verify fields. This is clear context for when to use this tool vs the many rcsb_get_* alternatives.

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