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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so 'Changes nothing' mostly restates the safety profile. The description's real added value is disclosing what the call actually returns (index verdict and reason, crawl data, canonical mismatch, structured-data errors), which matters since no output schema exists.

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?

Front-loads the resource and its payload, then the usage condition, then the side-effect note. Zero wasted sentences, though the dense field list is packed into one long clause and 'Changes nothing' is largely redundant with the readOnlyHint annotation.

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 no output schema, the description carries the burden of explaining returns and does so thoroughly; usage context and safety are also covered. Parameter limits live in the schema, so the definition is nearly complete for a two-parameter read-only inspection 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 100%: 'urls' documents the 20-per-call and 2,000/day limits, and 'site_url' documents the exact property format. The description adds nothing about either parameter, 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?

Names a specific verb (inspect URLs) and a specific resource (Google's index record per page), then enumerates the exact fields returned: index status and reason, last crawl, robots.txt/fetch result, Google-chosen canonical vs declared canonical, structured-data items. That level of specificity clearly separates it from search_console_performance or search_console_summary.

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 an explicit triggering condition: use it when a page gets no impressions or seems to have dropped, and explicitly before assuming a ranking problem. It does not name a sibling tool as the alternative (e.g. search_console_performance) or state when not to use it, so it stops short of a 5.

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