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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=true, and idempotentHint=false, covering the safety profile. The description adds that the tool is a single-call merger of three data sources, which is useful behavioral context, but it does not disclose auth prerequisites, rate limits, partial-failure behavior, or return format. That matches the calibration level for a description that adds some context while annotations carry the core behavioral disclosure.

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 definition is two sentences, front-loaded with the primary purpose and immediately followed by the alternative-tool routing advice. Every clause carries useful information with no filler.

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 read-only composite tool with no output schema, the description sufficiently explains what data is merged and when to prefer it, and annotations cover the safety profile. Minor gaps remain around what a caller should expect if one underlying source is unavailable or unauthorized (GSC access scope), but the definition is complete enough for correct selection and invocation.

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 parameters (site_id and detail) are already documented in the schema, including the concise/detailed verbosity behavior. The description adds no parameter detail beyond what the schema provides, so the baseline score of 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 states a specific composite verb and resource: 'One-call technical/indexing health for a site' and explicitly lists the three data sources it merges (Core Web Vitals, Search Console URL inspections, GSC access scope). It also distinguishes itself operationally from sibling tools by naming the exact chain it replaces (get_cwv_results + get_gsc_pages + get_index_status), so an agent can identify its role without opening the 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?

It gives explicit routing advice: 'Prefer this over chaining get_cwv_results + get_gsc_pages + get_index_status.' That names the alternative tools and the condition that selects this tool, leaving no inference required about when to call it instead of those siblings.

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