search_performance

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

With no annotations, the description carries the full behavioral burden. It usefully discloses a key trait—that Bing updates these statistics weekly, so data has a freshness lag—but says nothing about authorization needs (e.g., whether site_url must be a verified property) or pagination/limit behavior.

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 tightly written sentences with no waste. The metric list and dimension choices are front-loaded, and the weekly-update caveat follows immediately as the second relevant point.

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?

An output schema exists, so return-value formatting need not be explained. However, with no annotations and four parameters, the definition leaves behavioral gaps—no auth/read-only confirmation and no clarification of the limit parameter—making it only adequately complete for this tool.

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 adds real value by giving the valid dimension values ('query' and 'page') and clarifying that 'days' means the last N days, but 'limit' and 'site_url' receive no semantic explanation, leaving half the parameters documented only by their self-evident names.

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 the specific metrics returned (Bing clicks, impressions, CTR, average position) and the two grouping modes (queries via dimension="query", pages via dimension="page"). This distinguishes it reasonably well from siblings like traffic_trend and keyword_research, though it never explicitly names or contrasts those alternatives.

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 implies usage via 'top queries or pages over the last N days', which tells the agent what window and granularity to expect, but there is no explicit when-to-use, when-not-to-use, or named alternative among the sibling tools. Usage must be inferred.

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