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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered by structured data. The description adds useful legacy/deprecation context and notes the different return format, but doesn't detail the return shape or error behavior. Given annotation coverage, a 3 is appropriate—it adds some value without going deep.

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?

Three concise sentences in Japanese with the legacy status front-loaded before the functional explanation. The parenthetical site name adds a little noise but is minor. Efficient overall.

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, read-only, deprecated tool with no output schema, the description is fairly complete: it explains the purpose, the key difference from fetch, and when to choose fetch instead. The main gap is not explaining how the return format differs, but this is a minor omission given the tool's simple, legacy nature.

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%—the url parameter is fully documented in the schema (URL or path, Japanese characters acceptable). The description adds no parameter-level information beyond what the schema already provides, so the 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?

The description clearly states this tool returns the page body, positioning it as a legacy version of fetch. It explicitly distinguishes itself from the sibling fetch by noting the different return format, which helps an agent differentiate. It's clear enough but doesn't deeply specify what 'body' means or how exactly the return differs.

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?

This is exemplary guidance. The description explicitly names fetch as the alternative and gives a concrete directive: use fetch for new usage, and only use this tool for those already connected to the legacy version. This is exactly the kind of when/when-not/alternative routing the rubric asks for.

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