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

Annotations already establish readOnly, idempotent, non-destructive and openWorld. The description adds real value beyond them: the ten-result ceiling, the presence of content access labels, and specific data classes that are withheld (paid lesson bodies, drafts, customer data). It could still mention whether results are cached or paginated, hence 4.

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 sentences, no filler. The positive scope leads and the exclusions follow immediately, which is exactly the front-loaded ordering an agent needs.

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?

With an output schema present, return-value documentation is redundant, yet the description still summarizes it helpfully. Combined with the annotation coverage, an agent has enough to select and call it correctly; only query-formulation guidance is missing.

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. It partially does: 'English or Chinese' maps to the locale enum and 'up to ten' reflects the limit maximum. But nothing explains query syntax, length constraints or the limit default, so the schema still carries the bulk of the meaning.

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 (search) and precisely scopes the resource: Ecomwith published tutorial metadata, internal tool descriptions and public answer summaries. It also names the supported languages and the output shape (up to ten source links with content access labels), which the sibling tools (UTM builder, ROAS, profit scenarios, weekly reports) plainly are not.

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?

Explicit exclusions tell the agent when NOT to use it: the wider web, website fetching, paid lesson bodies, drafts and customer data. That is strong negative scoping. It stops short of naming a recommended alternative tool for those cases, so it is a 4 rather than a 5.

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