Search locations

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds genuinely useful context beyond that: the return carries a location_key that must be preserved verbatim, and that key encodes a location-language pair whose precision is lost if an @language qualifier is altered.

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 sentences, zero filler, purpose front-loaded and the usage directive immediately behind it. Every clause earns its place.

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 read-only three-parameter search with no output schema, an agent still lacks the shape of a result (name/key/language fields), the effect of 'country' vs. the query string, and any pagination behavior. The verbatim-key contract is well covered, but the surrounding result and filter semantics are not.

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 only 33%: 'q' is documented in the schema, but 'limit' and 'country' have no description in either place. The description mentions location_key and @language, which are not parameters at all, so it does nothing to compensate for the undocumented filtering and pagination parameters.

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 ('Search canonical keyword markets'), which is unambiguous and clearly a lookup/indexing tool rather than a keyword-mutating one. It doesn't explicitly name a sibling, but the market-lookup role is distinguishable from list_keywords, research_keywords, and get_keyword by domain.

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 a concrete when-to-use rule: call this before creating or updating keywords so the returned location_key can be reused verbatim. It does not name an alternative tool or state when not to use it, but the workflow positioning is clear enough to route invocation.

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