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

Annotations already declare it as a read-only, idempotent, non-destructive open-world call, so the safety profile is covered. The description adds real value beyond that: a ~3-day data lag, the required 'Siteiz Pro API key (Authorization: Bearer header)', and the notion that data is scoped to a 'connected' property. It doesn't mention rate limits or truncation behavior at the limit cap, keeping it out of 5 territory.

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?

Single front-loaded sentence that leads with the returned metrics rather than the tool name, which is the right ordering for an agent scanning for capability. The trailing auth note is compressed into a parenthetical; it earns its place but makes the sentence slightly dense.

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?

Output schema exists, all four parameters are documented, and the auth prerequisite and data freshness lag are both stated — the main things an agent needs before calling. Minor gaps remain around what happens when `limit` caps results and whether `site` is required in multi-site accounts beyond the schema's note.

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% and every parameter already carries a description plus defaults, so the schema does the heavy lifting. The description only echoes the dimension enum ordering ('by query, page, device or country') and the 'last N days' framing, adding little syntax or format meaning beyond the schema — the 3 baseline is correct.

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 resource and metric set ('Clicks, impressions, CTR and average position from your connected Google Search Console') along with the available breakdowns and time window. An agent can immediately tell this is the GSC performance-reporting tool and not the AI-visibility or crawler siblings.

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 context for when to reach for it: data from a connected GSC property, segmented by query/page/device/country, over the last N days. It does not name exclusions or point to a sibling (e.g. when to prefer get_ai_visibility_report instead), so it stops short of the explicit alternative-routing that a 5 requires.

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