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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is largely covered. The description still adds value beyond them: the auth prerequisite on the Caybl.ai connection and the fact that the call returns one of three verification artifacts. It does restate idempotency, which the annotation already carries, so it stops short of a 5.

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?

Four sentences, each carrying distinct information, with the core action and the three verification artifacts front-loaded. The 'Safe to call again' sentence partially duplicates the idempotentHint annotation, which is the only mild redundancy.

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?

No output schema exists, and the description compensates by naming exactly what comes back (CNAME record, meta tag, or XML file) and what to do next. Combined with the auth prerequisite and idempotency note, an agent has everything needed to invoke this correctly for a single-parameter 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?

There is a single parameter with 100% schema description coverage, including example formats ('example.com' or 'https://www.example.com/'). The description adds no additional semantics about siteUrl, so the schema does all the work and the baseline of 3 applies.

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 and resource ('Add a website to this Bing Webmaster Tools account') plus the concrete output ('a DNS CNAME record, a meta tag, or an XML file'). It explicitly separates itself from the sibling it hands off to ('call bing_verify_site'), so an agent can distinguish it from bing_list_sites and bing_verify_site without opening any schema.

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?

Gives the ordering rule ('After the record/tag/file is in place, call bing_verify_site'), the precondition ('Requires changes to be allowed on the Bing connection in Caybl.ai'), and the repeat-call behavior ('Safe to call again'). It also explains why verification matters ('Bing has no data for a site until it's verified'), which is real when-to-use guidance rather than filler.

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