get_dna_matches

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds valuable return-value context: each match reports total shared cM, largest segment, and any common ancestor, plus it explains the interpretive meaning of the data. It stops short of describing pagination, sorting, or the effect of include_raw.

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 front-loads the core purpose in the first sentence, then adds output details and domain caveats. It is somewhat prose-heavy, but the additional context about DNA evidence and `unattributed_count` earns its place for correct interpretation.

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 no output schema, the description carries the burden of explaining return values, and it does so by naming total shared cM, largest segment, common ancestor, and unattributed_count. It omits any mention of include_raw, but the input schema covers that parameter, so the definition is largely complete for an agent to call the tool correctly.

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 both parameters, including person and include_raw. The description does not add any parameter-specific syntax, format, or edge-case meaning beyond what the schema provides, so the baseline score of 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 states a specific verb and resource: 'List the DNA matches recorded against a person.' It is clear what the tool does, though it does not explicitly differentiate itself from sibling tools such as get_ydna or parse_dna_segments.

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 provides useful context about DNA evidence and points to `unattributed_count` as the key number for open research. However, it does not state when to use this tool versus alternatives like get_ydna, nor does it give explicit prerequisites or exclusions.

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