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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds one genuinely useful behavioral fact: results are scoped to data visible to the linked Market Brew account, which is an authorization/visibility constraint not expressed in the annotations. It still omits any note on result volume, pagination, or metric granularity.

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 with no padding, and the account-scoping caveat is placed where it will be read. The first sentence is largely wasted words since it only echoes the tool name, but the total length is tight enough that nothing is bloated.

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, read-only, zero-required-parameter tool with full schema coverage and annotations covering safety, the description is minimally sufficient. It does not say what metrics are returned or at what granularity, and there is no output schema to fill that gap, so an agent still lacks a clear picture of the result content.

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?

There is a single optional 'query' parameter whose nested filter fields are fully documented in the schema (100% coverage, including customerId, crewIds, websiteId, serverHost, startDate, endDate). The description contributes nothing about filter semantics or date-range behavior, so the baseline 3 applies when the schema carries the full burden.

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 verb+resource (get Search API metrics), so the action is identifiable, but the phrasing is effectively a restatement of the tool name and title with no differentiation from siblings such as get_ranking_sensor_metrics, get_crawl_metrics, or get_task_metrics. An agent cannot tell from this text what makes 'Search API metrics' distinct from the other metric tools.

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?

"Use this when the user asks to get Search API metrics" is a circular trigger that adds no routing information. No alternatives are named, no when-not-to-use condition is given, and nothing distinguishes it from the many other metrics retrieval tools in the sibling list.

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