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

Annotations already declare destructiveHint=true and idempotentHint=true; the description adds the key behavioral detail behind the destructive flag: 'Empty string clears,' which tells the agent how a value gets wiped. It also points to select_site for current state. No auth or partial-update semantics are covered, keeping it short of a 5.

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 short sentences, each carrying load: the mutation scope first, the sibling-differentiation caveat second, and the clearing/read-back semantics last. No filler or repetition.

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 4-param, no-required-field, no-output-schema mutation, the description covers scope, clearing behavior, and where to read current values. It leaves partial-update semantics (what happens to unmentioned fields) unstated, which is a minor gap.

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% so the baseline is 3, but the description adds real meaning: name is a URL slug, title/description are site-wide fallbacks, and empty string clears a field. That goes beyond the schema's field-level descriptions.

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 (Update) plus the resource and the exact fields it touches (name/URL slug, title, description). It is clearly separable from update_page, which it explicitly notes cannot reach the site-wide fallback fields.

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 context for use — these are fallback values for pages lacking their own SEO — and routes the agent to select_site to read current values. It does not state explicit exclusions or a when-not condition, but the alternative (update_page) is named and differentiated.

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