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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description usefully adds that the output is a set of sire/dam pairings rather than a single answer, but it says nothing about ordering, ranking, or what happens when no pairing is viable.

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?

A single sentence that front-loads the lookup type and then states the target and output shape; no wasted clauses. The 'Perform a reverse genetic lookup to' preamble is slightly ceremonious but does not obscure the core action.

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 responsibility for explaining returns; it does state that pairings (sire and dam) are returned, which is the key fact. It omits result ordering, behavior when no pairings exist, and how limit truncates the set, leaving a few gaps for a lookup tool.

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 target_variety (name or ID, case-insensitive) and limit (default 10). The description adds no format, matching, or truncation detail beyond what the schema provides, making the baseline 3 correct.

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 gives a specific verb (find) and resource (all possible parent pairings, sire and dam) plus the goal (producing a targeted plumage variety), which is far more informative than the tool name alone. It does not explicitly distinguish itself from the sibling predict_quail_cross, which appears to be the inverse operation, so it stops short of a 5.

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 'reverse genetic lookup' framing implies the scenario (working backward from a desired offspring variety to candidate parents), which is adequate implied usage. However, it names no alternative and gives no when-not guidance, so an agent must infer that predict_quail_cross is the forward-direction sibling rather than being told.

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