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

Annotations already declare readOnly/openWorld/non-destructive, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the ~6-month data horizon and, importantly, that it returns notConfigured: true when no Bing API key is configured — a non-obvious failure mode the agent must anticipate.

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 compact sentences, front-loaded with purpose, then data scope, then the notable edge-case return. No filler, though the Google-comparison sentence is more contextual than essential.

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 detail is unnecessary, and annotations carry the safety profile. The description supplies the data window and the notConfigured failure mode, leaving only minor gaps like auth requirements covered indirectly via openWorldHint.

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 67% and the startDate/endDate descriptions are already thorough (format, omit-both behavior, no-null warning). The description adds only "for a property" context and the 6-month default window; siteUrl itself is undocumented in both. Baseline 3 is appropriate given the schema does most of the work.

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+resource: daily clicks and impressions from Bing Webmaster Tools for a property, and clarifies it covers Bing/Yahoo/DuckDuckGo organic. An agent can distinguish it from other Bing tools (crawl, query, page stats), though no sibling is named explicitly.

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?

"Complements Google Search Console data with the Bing side of organic search" gives a reasonable context for when the tool is relevant, but there is no explicit when-to-use vs alternatives guidance or exclusions. Usage is implied rather than stated.

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