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

Annotations already declare this is a non-read-only, non-idempotent, open-world write, so the safety profile is covered. The description adds genuinely new behavioral context beyond them: the 500-address cap, the ~10,000/day per-site quota and that remaining quota is surfaced, and the account prerequisite. It does not say how partial failures or rejected URLs are reported.

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 front-loaded sentences, with the action and its limits stated before the alternative-tool routing. The first sentence is dense with nested parentheticals, which slightly taxes readability, but no sentence is 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?

No output schema exists, but the description covers the mutation's constraints, quota behavior and the alternative route, and annotations carry the safety hints. It stops short of explaining what a submission result or a failure looks like, which is the main remaining gap for a write tool.

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 documents site, urls and sitemap. The description adds only the volume ceiling on urls, not format or validation semantics. Baseline 3 is correct when the schema does the heavy lifting.

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?

Specific verb and resource ('Ask Bing to crawl pages now', submit addresses or a sitemap) with concrete scope limits (up to 500 addresses, ~10,000/day per site). It also names the sibling it overlaps with (indexnow_submit), so an agent can distinguish it without opening either 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?

Explicit trigger ('Use after publishing or changing pages') plus an explicit alternative and the condition that selects it: prefer indexnow_submit when no account exists, prefer this when Bing is connected and the user wants Bing's own confirmation and quota.

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