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

With no annotations, the description carries the full burden and does substantial work: it defines the 'breakout' test, clarifies that neverAdopted does not mean zero bearers, and warns that names first recorded in 1910 or earlier list all 51 states. It omits return format, pagination, and any permission/rate-limit behavior, keeping it short of 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?

Three sentences, front-loaded with what is returned before the interpretive caveats. Dense but every sentence carries meaning; only mild compression is possible.

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?

No output schema exists, so the description must convey the return shape, and it does list the principal outputs plus two important edge-case behaviors. It stops short of naming every returned field, leaving some ambiguity about field names such as the breakout states list.

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% with only two parameters, so the schema already documents 'name' and the 'sex' enum fully. The description adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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 ('Returns') and resource ('geographic spread of a name over time') and then enumerates exactly what the payload contains: first breakout location, national peak, state-level breakout timing, and non-adopters. 'Geographic spread over time' is distinct from the sibling tools that deal with debuts, decade/year data, or comparisons.

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?

No explicit when-to-use statement or named alternative among siblings like compare_names or get_name_debuts. Usage is only implied by the output description, though the caveats about neverAdopted and pre-1910 names do help an agent interpret results correctly once the tool is chosen.

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