index_now

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

With no annotations, the description carries the full disclosure burden. It transparently explains the API submission behavior, return format, and error types. It also states it's free and uses a shared key. However, it does not mention rate limits or potential side effects on the user's account, which would enhance completeness.

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 very concise: three sentences covering purpose, cost/credentials, and return/errors. It is front-loaded with the primary action. Every sentence adds value with no redundancy.

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 API submission tool, the description sufficiently covers the purpose, supported engines, cost, return format, and common errors. It lacks details on prerequisites (e.g., URL validity or domain ownership) and daily limits, but overall it is adequately complete given the lack of output schema and simple parameter schema.

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?

The input schema already describes both parameters (url and urls) with clear descriptions and constraints. The description adds context about submitting 'one or more URLs' but does not provide additional semantics beyond the schema. Given 100% schema coverage, a 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 clearly states the action: 'Submit one or more URLs to the IndexNow API for instant search-engine indexing' and specifies the target search engines (Bing, Yandex, Naver, Seznam) and excludes Google. This distinguishes it from sibling tools which focus on analytics, social posting, or content management.

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 provides context on when to use (for submitting URLs to indexing across specific engines) and notes that no platform credentials are required and it's free. It also lists common errors, aiding proper usage. However, it does not explicitly contrast with sibling tools or mention when not to use, but the distinct purpose makes it clear enough.

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