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

Annotations declare readOnlyHint=true and destructiveHint=false, so the tool is safe to call. The description adds that it reports data from the 'URL Inspection API', which implies a read-only, query-based behavior. It also specifies the output fields (indexed, last crawled, canonical), which is useful context beyond the annotations. However, it doesn't disclose potential rate limits or authentication requirements, but given the read-only nature, this is minor.

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?

The description is a single, concise sentence that front-loads the core purpose and output. It avoids fluff and every word adds value. It is well-structured and immediately actionable.

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?

The tool is simple with 2 parameters, a full schema, and no output schema, so the description doesn't need to explain return values. The description covers the key behavioral aspects (what it returns) and usage context. It is complete for an agent to call it correctly, though it could mention the 'site' parameter's optionality in the description, but the schema already does that.

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%, so both 'url' and 'site' are fully described in the schema. The description adds minimal additional parameter context; it mentions the 'site' parameter as 'Search Console property' in the schema but doesn't specify the format in the description. The baseline is 3 because the schema does the heavy lifting.

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 states a specific verb ('inspect'), a specific resource ('URL'), and the exact output (indexed status, last crawl, canonical). It clearly distinguishes itself from sibling tools like 'top' and 'query' which are about performance and rankings, not index status. The title reinforces the purpose, and the description adds detail beyond the title by mentioning the three key data points returned.

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?

The description clearly states when to use this tool: when you need index status for a specific URL. It implicitly contrasts with siblings like 'page_queries' and 'query' which are about search queries, and with 'find_cannibalization' which involves multiple URLs. However, it doesn't explicitly state when NOT to use it (e.g., for bulk indexing or for performance metrics), but the context is clear enough.

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