Japan Earthquake Alerts MCP

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the source (JMA), result count (newest 5), and returned fields (intensity, epicentre), plus that access is free. It says nothing about refresh cadence, ordering, or failure behavior, which leaves real gaps for a no-annotation tool.

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 tight sentence with the most important scope detail, 'newest 5', front and center. The leading 'FREE.' is mildly promotional rather than operational, but it is short and not distracting.

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 zero-parameter read tool with no output schema, the description covers source, result size, and key fields, which is close to sufficient. Freshness and ordering are left implicit, keeping it from a 5.

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 the baseline is 4. The description correctly implies no inputs are needed to retrieve the latest events.

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 names a specific resource and scope: latest Japan earthquakes from JMA, returning the newest 5 with intensity and epicentre. That is far more specific than the tool name alone. It does not explicitly distinguish itself from quake_search or realtime_feed, 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?

'Latest' and 'newest 5' imply this is for a quick look at recent events rather than a historical query, which hints at when to prefer it over quake_search. However, it never names an alternative or states an exclusion, so guidance is only implied.

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?

No annotations exist, so the description carries the full burden, yet it discloses almost nothing behavioral: no auth requirement (the token gating is only implied by 'PRO'), no ordering or recency semantics, no pagination or truncation behavior beyond the 100 cap, and no detail on what a bulletin contains. 'Up to 100 recent' is the only real behavioral constraint offered.

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 compact sentences with the key facts front-loaded; almost no waste. The leading 'PRO.' fragment is cryptic and slightly bloats the front, but overall it is tight and readable.

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 tool with zero annotations, no output schema, and a partially documented schema, the description is too thin: an agent lacks the auth prerequisites, result ordering, and sibling differentiation needed to invoke it confidently. The intensity-scale example is the one genuinely valuable piece of context provided.

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?

With only 33% schema coverage, the description must compensate, and it partly does: it defines limit as bounded at 100 and gives concrete examples for min_intensity ('3, 4, 5弱') including the non-obvious Japanese intensity scale format. However, access_token handling is described only in the schema, and the description adds no further meaning on how min_intensity filtering interacts with the result cap.

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 resource (recent JMA quake bulletins) with a concrete cap (up to 100) and an optional intensity filter, which is far more informative than the bare name. It does not distinguish itself from siblings like latest_quakes or realtime_feed, so an agent cannot tell from the text why it should pick this one.

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 latest_quakes or realtime_feed, which are obviously overlapping quake-retrieval tools. The only usage signal is the implicit 'PRO'/subscriber framing and the optional intensity filter, leaving the agent to infer selection.

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?

No annotations exist, so the description carries the full burden. It weakly signals an auth tier via "PRO" (consistent with the access_token parameter), but says nothing about how recent "near-realtime" actually is, whether results are cached/delayed relative to JMA, rate limits, or how many records come back by default.

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 short sentence with the resource and the upstream source front-loaded; nothing is padded. The "PRO" prefix is terse but carries real meaning about access tier, so the brevity is not waste — the problem is missing content, not excess.

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 data-feed tool with no annotations and no output schema, the description should say what a returned item contains (magnitude, location, time), how fresh it is, and what limit defaults to. None of that is present, so the agent must guess at result shape and volume.

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 only 50%: access_token is documented in the schema, but limit has no description anywhere. The description does not explain what limit bounds (count of events? JSON keys?) or its default/max, and "PRO" only obliquely explains the token parameter, so it fails to compensate for the coverage gap.

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?

"Recent felt earthquakes via P2PQuake (code 551)" names the resource, the upstream source, and the feed's nature, which is more than a tautology. But there is no verb, and the description never distinguishes this from the sibling latest_quakes, which sounds like it returns the same thing; an agent cannot tell which one to call first without opening both schemas.

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 near-realtime mirror of JMA reports" hints at a freshness-oriented use case but gives no explicit when-to-use, when-not, or alternative. Nothing tells the agent whether this or latest_quakes/quake_search is the right entry point for a given query.

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