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

No annotations are provided, so the description carries the full behavioral burden and falls short: it never says what the tool returns (boolean vs. structured result), how it treats timezones or the boundary case where the timestamp equals now, or what happens with an unparseable input. It conveys the predicate's meaning but no operational traits.

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?

Two short sentences, front-loaded with the core predicate followed by the use case; no filler. Slightly more could be said about parameter usage without bloating it, but as written every sentence earns its place.

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 simple predicate with no output schema and no annotations, the description covers the core semantics but leaves the biggest practical gap unresolved: with zero required parameters and two ambiguously named inputs, an agent cannot tell from the description alone how to actually invoke it 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 coverage is 100%, so the baseline is 3, and the schema's own descriptions ('Date to process', 'Value to process') are vacuous. The description partially compensates by hinting that either a date or a timestamp form is accepted, but it never disambiguates the two oddly-named parameters ('date' vs 'value') or says whether both can/must be supplied.

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 predicate ('check whether a given date or timestamp is in the past relative to now') with a clear reference point ('now'), which unambiguously separates it from the complementary x402-is-future / x402-is-today siblings by semantics. It does not, however, name any sibling explicitly, so an agent must infer the routing from wording alone.

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?

'Useful for deadline or expiry checks' gives one concrete usage scenario, which is more than nothing. But there is no guidance on when NOT to use it or which sibling to prefer (e.g. is-future, days-since, days-until) when the same intent could be expressed differently.

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