jma_get_volcano_warnings

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

With no annotations, the description carries the full burden and does well: it enumerates returned fields, decodes JMA status wording (火口周辺規制, 周辺海域警戒), and defines negative-result semantics. It does not explicitly state read-only/idempotent behavior or any auth/rate constraints, which is a minor gap for an unannotated 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?

Front-loaded with the core purpose and scoped in a handful of dense sentences; the parenthetical JMA wording glossary is informative but bulky. Nearly every clause earns its place, with only mild redundancy against the schema's own examples.

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?

With one optional parameter and no output schema, the description must describe the return payload itself, and it does: fields, level meanings, raise/lower indicators, and empty-feed interpretation. Nothing an agent needs to call or interpret this tool is missing.

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% and the schema already documents the volcano parameter with examples, so the description's restatement of Japanese/romaji names and JMA codes adds little beyond it. The additional value is interpretive context about alert levels, not parameter semantics, so baseline 3 applies.

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 and resource ('Lists volcanoes in JMA's current eruption-warning feed') and names the concrete payload: alert level 1–5, status wording, raise/lower flags, municipalities, coordinates. This clearly separates it from generic warning feeds, but it never names the sibling jma_get_warnings or explains how the two differ, so sibling differentiation is left to inference.

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?

Explains the optional-filter workflow and gives the key interpretive rule that a volcano absent from the feed has no warning in effect, which tells the agent how to read an empty result. It stops short of saying when to prefer this over jma_get_warnings or jma_find_area for related queries.

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