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

The description goes well beyond the annotations by disclosing a 43 MB response, that it is the largest response in the provider by two orders of magnitude, and that it is free upstream with no billing signal. This is crucial safety-relevant behavior that readOnlyHint and idempotentHint do not convey.

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?

Every sentence earns its place: the core purpose, a loud warning with quantitative evidence, a concrete example, and the billing caveat. The warning is front-loaded and the red emoji draws attention without adding noise.

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?

The description is complete for a zero-parameter tool with an output schema. It tells the agent what the resource is, why not to fetch it, how to obtain the data instead, and the key behavioral risk. The output schema covers return-value structure, so nothing necessary for correct use 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?

The input schema has no parameters, so there is no parameter burden on the description. Despite zero params, the description adds semantic value by giving a concrete location_code example (2840 = United States) and pointing to documentation for other codes, which helps an agent interpret output rather than requiring schema documentation.

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?

The description and title clearly identify the resource as the list of locations accepted by Google Shopping endpoints. It is distinguishable from sibling tools like get_dataforseo_merchant_google_languages and Amazon-specific location tools by the explicit 'Google Shopping' and 'locations' scope, though it does not explicitly name those 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?

The description gives explicit guidance: 'Do not call this from an agent.' It also provides an alternative action ('look other codes up in DataForSEO's documentation') and explains why the tool is unsafe for agent invocation due to response size. This is strong when-to-use and when-not-to-use direction.

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