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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds useful behavioral detail: the 50-number batch limit and the exact return fields, including what works_elsewhere means. It does not explain error handling or the conflict with the schema's maxItems of 100, keeping it from a 5.

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 definition is front-loaded with the use case, followed by the limit and return fields in a compact sequence. Every sentence adds actionable information 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?

For a read-only batch lookup with no output schema, the description enumerates the key return fields and clarifies works_elsewhere, which is valuable. However, the 'Up to 50 numbers per call' statement conflicts with the schema's maxItems of 100 and no explanation is given, leaving a small completeness gap.

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 100%, so the schema already documents the single ipi_name_numbers parameter. The description repeats the 50-number limit and gives input-context examples, but adds no syntax, format, or constraint detail beyond what the schema provides. Baseline 3 is appropriate.

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 a batch lookup of songwriters by IPI name number and what each result contains. The plural 'several IPI name numbers' and 'Up to 50 numbers per call' distinguish it from singular siblings like get_songwriter and find_songwriter.

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 explicitly says when to use the tool: when the user has several IPI name numbers, such as writers on a song, catalogue, or registration file. It does not name when not to use it or explicitly route single-number cases to a sibling, so it stops short of a 5.

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