Site overview

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

Annotations already declare readOnlyHint=true and openWorldHint=true. The description adds useful behavior: comparison against the previous period, pages that gained/lost, and up to 3 recommendations. It does not disclose deeper behaviors like data limits, pagination, or interpretation caveats, but given the read-only annotation the safety profile is covered.

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 key metrics and ends with a clear call to action. Every phrase contributes information, with no filler or repetition of the tool name.

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?

For a simple 2-parameter overview tool, the description covers the main output elements: key metrics, comparison period, page changes, and recommendations. There is no output schema, so the description reasonably conveys what the agent can expect. It does not detail return formatting or exact comparison calculations, but these are minor for this tool's simplicity.

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 the schema fully documents both parameters. The description's 'vs the previous period' aligns with the days parameter but adds no new semantic detail beyond what the schema already states. Baseline 3 is appropriate.

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 clearly states the tool's content: clicks, impressions, CTR, average position, top gaining/losing pages, and recommendations. It is distinct from siblings like inspect_url or search_performance by describing a site-level overview, though it does not explicitly name alternatives or use a strong imperative verb.

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 phrase 'Start here' gives explicit guidance that this is the entry-point tool for site analysis. It establishes clear context for when to use it, but it does not mention when not to use it or explicitly route to alternatives such as find_opportunities or search_performance.

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