Japan Public Holidays MCP

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

No annotations exist, so the description carries the full burden, yet it only discloses the date format and the 'PRO' tier marker. It says nothing about the return value (a boolean?), behavior on invalid or non-existent dates, or that access_token is needed to avoid rejection beyond what the schema hints.

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?

One sentence plus a tier marker, front-loaded with the key format constraint and free of filler. 'PRO.' is terse to the point of being cryptic but it is at least compact.

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 two-parameter lookup with a self-evident boolean result and no output schema, the description is close to sufficient. The remaining gap is failure behavior for malformed dates and what the PRO label implies for auth.

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 50%: access_token is documented in the schema, and the description compensates for the bare `date` parameter by specifying the YYYY-MM-DD format. That is a genuine addition beyond the schema, though nothing is said about range limits or timezone assumptions.

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 verb ('Check whether') plus a precise resource ('a Japanese public holiday') and pins the input format YYYY-MM-DD, so its job is unambiguous. It doesn't explicitly contrast itself with next_holidays or year_list, which is the only thing keeping it from 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?

There is no statement of when to use this versus next_holidays (upcoming holidays) or year_list (bulk enumeration). The agent must infer the routing from the names alone.

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

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

With no annotations, the description carries the full burden, and it does disclose the return cardinality (5 items), the domain (Japanese public holidays), and the starting point (today), plus a cost cue ('FREE'). It says nothing about the timezone basis for 'today', the fields in each entry, or invocation limits.

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 cost signal and immediately followed by the concrete output scope. Nothing in the text is wasted or repetitive.

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 trivial no-argument tool this is close to sufficient, but with no output schema the description is the only source of return-shape information and it omits what fields each holiday record contains and which timezone 'today' refers to.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline for a parameterless tool applies. The description correctly implies no inputs are needed.

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: it returns the next 5 Japanese public holidays from today. That scope implicitly separates it from siblings like is_holiday (single-date check) and year_list (full-year listing), though it never names those siblings explicitly.

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?

'Next 5 ... from today' implies the appropriate use case: a zero-argument lookup of upcoming holidays. However, there is no explicit when-to-use or when-not guidance pointing to is_holiday or year_list, so the agent must infer the boundary from the description's phrasing.

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

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

With no annotations, the description carries the full disclosure burden. It does add two useful traits: 'PRO' signals a paid-tier/entitlement requirement, and 'typically current + next year' warns that coverage varies by dataset rather than being fixed. It says nothing about return size, ordering, pagination, or whether past years are included, which matters for a bulk-list endpoint.

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 fragments with no filler, but the lead position is spent on the opaque 'PRO.' marker rather than the core behavior. It is terse to the point of under-specification rather than genuinely front-loaded.

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 one-parameter, no-output-schema listing tool, the description covers the essential question: what data comes back and how far it spans. Remaining gaps (ordering, exact year boundaries, response shape) are modest given the tool's simplicity and the fully documented parameter.

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?

Only one parameter exists and the schema documents it fully ('Subscriber token from /success'), so the schema does the heavy lifting. The description's 'PRO' hint loosely corroborates the token's subscription semantics but adds no new detail about how the token is passed or what happens if it is omitted (0 required parameters).

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 clear resource and scope: 'All holidays in the dataset (typically current + next year)'. An agent can tell this returns a full list rather than a per-date check, but the contrast with siblings like next_holidays is only implied, never stated. The leading 'PRO.' token is unexplained jargon that occupies the most prominent position without clarifying purpose.

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 guidance on when to call this versus is_holiday or next_holidays. The scope phrase 'all holidays in the dataset' weakly implies a bulk-listing use case, but no alternatives, prerequisites, or exclusions are named.

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