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

Annotations already declare destructiveHint=true, but the description adds genuinely new behavioral facts: the operation is irreversible (元に戻せない), the API key/connection settings survive, and re-registering the profile restores usability. It also discloses the exact confirmation string required to proceed, which annotations cannot convey.

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?

Content is front-loaded: scope, then gating condition, then procedure, then irreversibility. Every sentence adds unique information, though the indented multi-line formatting is slightly sprawling for four short statements.

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?

An output schema exists, so return values need no explanation. The description covers everything else an agent needs for a one-parameter destructive tool: what is destroyed, what persists, the confirmation contract, and the irreversibility warning.

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 description coverage is 0% for the single 'confirmation' parameter, so the description must carry the burden — and it does, specifying that the value must be exactly 「すべて削除する」. Without this the agent could not invoke the tool correctly at all.

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 precise verb (削除する) and enumerates the exact resources affected: 会社プロフィール・ウォッチリスト・既読情報・申請書類（案件と記入内容）. No sibling tool performs deletion, so the scope statement alone is enough for an agent to identify this as the sole destructive data-removal tool.

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?

It gives an explicit gating condition ('ユーザーが明示的に削除を依頼した場合のみ使う') and a required pre-execution procedure (explain the deletion set, obtain confirmation). This is stronger than a typical when-to-use statement because it also forbids speculative invocation.

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