we_preview_close

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

Annotations already declare readOnlyHint=false, openWorldHint=false and destructiveHint=false. The description adds real context beyond them: the operation is scoped to windows created by this server session and deliberately omits global stop/kill semantics, which tells the agent about blast radius. It does not say whether closing is idempotent or what happens on an unknown id.

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 short sentences, no filler, with the scope constraint front-loaded rather than buried.

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 teardown tool with annotations and no output schema, the description covers the essential scope restriction. Minor gaps remain: no mention of idempotency or behavior for an invalid/already-closed previewId.

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%, and the description never mentions previewId, its UUID format, or where the id comes from (presumably we_preview_open). The name plus the UUID pattern in the schema make it inferable, so this is adequate but adds nothing beyond structured data.

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 ("Close") and resource ("a window created by this server session"), which is specific enough to separate it from we_preview_open and from any global kill sibling. It does not name an alternative tool, so it falls short of the 5 bar.

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?

"No global stop/kill commands" is an exclusion rather than a when-to-use rule; the agent can infer it is for tearing down a preview it opened, but no explicit trigger or alternative tool is named. Implied usage only.

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