Marginalia 検索 URL 生成（独立系・非商業サイト優遇）

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

With no annotations, the description carries the full burden of behavioral disclosure. It transparently reveals that Marginalia is English-only, Japanese queries fail, the service is mid-migration with unstable HTML, and automated fetching should be avoided. This is rich, candid context beyond minimal expectations.

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?

The description is well-structured, front-loading the core purpose in the first sentence, followed by clearly marked constraints. Every sentence earns its place, providing necessary context without fluff.

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 single-parameter tool with no output schema, the description is highly complete: it explains what the tool does, its constraints, how to use it (browser-based), and when to use alternatives. There are no obvious gaps for an AI agent to 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?

The schema already describes the single 'query' parameter as '検索語（英語のみ有効）', and the description reinforces this English-only constraint. Since schema description coverage is 100%, the description adds no significant new parameter-level meaning beyond restating the constraint; the baseline is 3.

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 uses a specific verb and resource: 'assemble the search URL' for the Marginalia search engine. It clearly differentiates from siblings by describing Marginalia's niche (favoring low-commercial personal sites and old pages) and explicitly contrasting with wayback_* tools.

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?

The description gives explicit when-to-use guidance: it states the tool is for generating Marginalia search URLs, and provides clear exclusions—Japanese queries yield no results, results should not be auto-fetched (browser viewing is expected), and for Japanese old-site bodies one should use wayback_* tools instead. This directly names alternatives.

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