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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds real value with 'deterministic' (stable result per date) and 'hydrated at read time' (content is populated on demand), but stays silent on pagination behavior despite limit/cursor parameters.

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 resource and scope front-loaded and no filler. Every clause ('daily', 'deterministic', 'UTC date', 'hydrated at read time') carries information.

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 three-parameter tool with 0% schema description coverage and no output schema, the description omits pagination semantics for limit/cursor and does not clarify what the digest contains. It is adequate for the date argument alone but incomplete overall.

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 0%, so the description must carry the parameter burden; it only restates the date format already encoded in the schema pattern and says nothing about limit or cursor. Two of three parameters are left entirely unexplained.

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 clear resource ('match digest') scoped to a UTC date, with the differentiating qualifier 'deterministic' distinguishing it from the likely-sibling suggest_matches. It doesn't explicitly name a sibling, but an agent can infer this is a cached per-day snapshot rather than a live query.

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?

There is no explicit when-to-use guidance or comparison to alternatives such as suggest_matches, which appears to serve a similar matching purpose. The word 'daily' implies a per-date cadence but does not say when this should be preferred.

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