check_merchant_center

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds meaningful context beyond them: it explicitly states no Merchant Center login is needed and that the check compares markup against the rendered page. It stops short of describing return shape or fetch/rate behavior.

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 dense sentences: the check list comes first, the scope/auth caveat second. No filler, no restatement of the tool name.

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 read-only tool with no output schema, the description covers what is examined and what is out of scope. The remaining gap is that an agent cannot anticipate the result shape (pass/fail per check, findings list) since no output schema exists.

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?

There is a single parameter with 100% schema description coverage, which already establishes the baseline of 3. The description reinforces that the URL must point at one public product page, but adds no format or validation detail beyond the schema's example.

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+resource ('Check one product page for Google Merchant Center problems') and enumerates the exact checks performed (price/availability mismatch, duplicate Product blocks, missing identifiers). It is clear about scope but never names the siblings (audit_store, check_ai_shopping_readiness) it should be preferred over.

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 'Page-level only; it does not log in to Merchant Center' clause sets a boundary, implying this is a single-page public check rather than a store-wide or account-level audit. However, it never explicitly says when to choose this over audit_store or check_ai_shopping_readiness, leaving routing to inference.

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