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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, covering the mutation and idempotency profile. The description adds the paid-plan restriction, which is useful behavioral context. However, it does not explain null-value semantics (likely clearing fields) or error behavior, leaving some gaps beyond what annotations provide.

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?

A single, direct sentence that front-loads the action and constraint. No wasted words; every element earns its place.

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 simple tool with 3 parameters and no output schema, the description is adequate but incomplete. It lacks clarification on null semantics, potential errors, and what a successful call returns. Given the low schema coverage, more detail would help, but the tool's simplicity keeps the baseline acceptable.

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%, so the description must compensate for parameter meanings. The description only refers to 'SEO title/description' collectively, giving no detail on metaTitle, metaDescription, or siteId. It does not explain that null values are allowed or what they signify, so agents are left without critical parameter guidance.

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 the verb 'Set', the resource 'SEO title/description of a site', and adds a qualifying constraint ('paid plans'). This distinguishes it from general site update tools like update_site and set_search_indexing, making the purpose unambiguous.

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 provides a specific condition ('paid plans') but does not explicitly mention when to prefer this tool over alternatives such as update_site or set_search_indexing. The guidance is implied rather than explicit, and no when-not-to-use exclusions are given.

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