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

Annotations already cover readOnlyHint=false, idempotentHint=true, and destructiveHint=false. The description adds value beyond annotations by clarifying that the key must be hosted and controlled by the user, and by stating the intended effect (near-instant indexing by Bing and Yandex). No contradiction with 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?

Two sentences with no wasted words. The core action and purpose are front-loaded, and the critical prerequisite appears immediately after. Every clause contributes necessary information.

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 two-parameter mutation tool with idempotent and non-destructive annotations and no output schema, the description provides sufficient context: target service, key prerequisite, and purpose. Minor gaps like response handling and same-host constraint exist, but the latter is already in the 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?

Schema description coverage is 100%, so the schema already fully documents both parameters. The description reinforces the key-hosting requirement and supports one-or-many URLs, but adds no additional format or syntax details beyond the schema. 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?

States a specific verb ('Submit') and resource ('URLs to IndexNow'), names the search engines (Bing, Yandex), and clearly distinguishes itself from the unrelated sibling SEO tools. No ambiguity about what this tool does.

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?

Clear use case: submit URLs for near-instant indexing. The description provides a necessary prerequisite (hosted key) and explicitly notes the tool does not create the key, helping the agent decide whether it can use the tool. No explicit alternatives are named, but no sibling tool competes with this functionality.

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