keywords_for_site

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

Annotations already cover readOnly/openWorld/idempotent/destructive, but the description adds genuinely new context: a sandbox mode returning dummy data with no payment, which implies production calls are billable. It also briefly names the return shape, useful since there is no output schema. No explicit statement about rate limits or pricing beyond the sandbox hint keeps it from a 5.

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?

Three tight sentences, front-loaded with what it returns, followed by the routing rule and the sandbox caveat. Every sentence carries distinct information; the parenthetical provider attribution is cheap and helps traceability.

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, yet the description names the return keys (domain, total_available, keywords) and flags the sandbox data caveat. Combined with fully documented params and annotations, an agent has everything needed to call it and interpret the response.

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 domain, language_code and location_code (including defaults and rejection of IPs/ports) are fully documented in the schema. The description mentions only 'domain' implicitly and adds no format or syntax guidance beyond it. Baseline 3 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?

States a specific verb and resource with scope ('Up to 25 Google keywords relevant to a website') and enumerates the metrics returned. It also names the sibling it is NOT (ranked_keywords), so an agent can disambiguate 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?

'Use it to find what a site should target; use ranked_keywords for what it already ranks for' gives an explicit when-to-use plus the alternative and the condition that selects it. Nothing is left to inference.

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