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

Adds substantive context beyond the annotations: it clarifies that nothing on the site is deleted or changed, that the side effect is an external, non-withdrawable notification, and that repeated calls each emit another one — which explains the idempotentHint=false and destructiveHint=true flags rather than merely restating them. It also sets expectations for the result ('says only that the notification was submitted, never that indexing will happen'). The wording 'deletes and changes nothing on the site' sits in mild tension with destructiveHint=true, but it is an explanatory nuance about irreversibility rather than a real contradiction; quota or rate-limit behaviour is not stated.

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?

Front-loaded with the action, then a clearly signaled 'Read before using' block that puts the critical limitation before the alternatives. Dense but almost every sentence adds decision-relevant information; the 'does NOT get an ordinary page crawled or indexed' clause and the alternatives list overlap slightly, costing a little tightness.

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 one-parameter, irreversible side-effect tool whose output schema already defines the response shape, the description covers the action, the eligibility trap, the irreversibility, and the fallback path. Nothing an agent needs to decide whether or how to call it is missing.

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 0% and the single required `url` parameter has no title or description, so the description must carry the load. It implies `url` is the page being notified, but never says whether it must be a fully qualified URL, must belong to a verified Search Console property, or what format is rejected. Helpful but not compensating for the coverage gap.

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?

Names a specific verb and resource: send a URL_UPDATED notification for a URL to Google's Indexing API. It immediately narrows scope by stating which pages the API actually acts on (JobPosting, or BroadcastEvent inside VideoObject) and names the sibling to consult first (gsc_inspect_url), so an agent can separate it from gsc_inspect_url, gsc_submit_sitemap, and site_index_audit without opening any 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?

Gives explicit when-to-use (pages with the qualifying structured data) and when-not (any ordinary page, since Google accepts and ignores the notification). It routes the agent to concrete alternatives for ordinary pages — internal links, honest sitemap lastmod, pruning low-value URLs, the manual URL Inspection button with its ~10/day limit — and prescribes a precondition ('Check the page with gsc_inspect_url first').

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