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

Annotations already establish readOnly, idempotent, non-destructive and closed-world behavior, so the description only needs to add operational context. It does usefully disclose the output shape (best and worst matching years) despite there being no output schema, but it leaves open whether all intermediate scores are returned or only the extremes, and it never explains the "Vietnamese age-matching rules" it relies on.

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 tightly packed sentence with the core action and return value front-loaded and no filler. It could be split slightly to separate input contract from return contract, but nothing here is wasted.

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 four-parameter, read-only scoring tool with no output schema, the definition covers inputs and outputs at a workable level and annotations carry the safety profile. It falls short on explaining the scoring rules and the best/worst result semantics, which is the main thing an agent would want to know before invoking it.

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 coverage is 75%, so most parameters are already documented, including the range default of 10 and the partner_gender default. The description only adds a marginal gloss by tying birth_year and gender to "one person" and confirming that a range is scanned; it does not clarify how range bounds are applied.

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 ("scores"), a specific resource ("every partner birth year within a range") and states the return ("best and worst matching years"). It implicitly distinguishes itself from check_age_compatibility by scanning a range rather than one pair, but it never names that sibling, so the differentiation is inferred rather than stated.

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?

Usage is implied: supply one person's birth year and gender when you want to explore a span of candidate partner years rather than test a single match. There is no explicit when-not guidance and no alternative tool named, so the agent must infer that check_age_compatibility is the right choice for a single pair.

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