Validate IndexNow key setup

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds value by stating 'The key is never returned' — a meaningful behavioral disclosure about output confidentiality. It also reveals it performs a remote check (public accessibility, host location), which is useful operational context beyond the annotations.

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?

One sentence, zero waste. Front-loads the verb and subject, lists the three check criteria compactly, and adds the key confidentiality note as a meaningful final clause. Every element earns its place.

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 single-parameter read-only validation tool with complete schema coverage and good annotations, the description covers the essential behavioral points: what is checked, the fact that the key is never returned, and the tie to a verified site URL. It doesn't describe failure modes or return values, but given no output schema exists and this is a straightforward validation check, the coverage is reasonably complete.

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 coverage is 100% for the single parameter, documenting it as an 'Exact verified site URL returned by bing_list_sites'. The description adds context by implying the site_url determines which site/domain's key file to validate against, and that the verified URL's host matters for the host-location check. With one well-documented parameter, the description's contribution is modest but adequate.

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 uses a specific verb ('Check') with a clear resource ('IndexNow key file') and enumerates three concrete criteria: publicly accessible, contains the configured key, and on the configured site's host. It clearly distinguishes itself from sibling tools like indexnow_submit_url/indexnow_submit_urls, which submit URLs rather than validate key setup.

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 states the tool checks local key configuration but doesn't explicitly state when to use it vs alternatives (e.g., before submitting URLs). It implies it's a prerequisite verification for IndexNow submission workflows but doesn't name any alternative or exclusion conditions. The sibling names suggest it pairs with indexnow_submit_* tools, but this isn't stated.

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