Get targeting options

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful behavior context — that the returned lists are often long and that search narrows them — but says nothing about how max_results caps the result or whether the call needs an ad account for certain targeting types.

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?

Very short and front-loaded: purpose first, then the allowed values, then the search behavior. The opening fragment ('Valid values for an ad group targeting_spec field.') is slightly clipped but every sentence carries information.

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 enumeration lookup with an output schema present, the description covers the essential decision inputs: which targeting_type values are legal and how to narrow long lists. The remaining gap — whether ad_account_id is mandatory for audience targeting types — is meaningful but secondary given the output schema and annotations.

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 0%, so the description carries the full burden. It does well on targeting_type (all ten legal values) and on search (with a concrete example), but max_results and ad_account_id are never mentioned, leaving half the parameters undocumented in either structured or prose form.

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 states the resource precisely: valid enumeration values for an ad group targeting_spec field, and enumerates the ten accepted targeting_type values, which lets an agent recognize it as a lookup/enumeration tool. It stops short of an explicit verb phrase and never contrasts itself with nearby siblings such as list_targeting_templates or estimate_audience_size.

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?

Usage is implied rather than stated: an agent can infer this is the tool to call to discover legal values before writing a targeting_spec. The search example (search='united kingdom') gives useful invocation context, but there is no explicit when-not guidance and no named alternative for template- or audience-size-related needs.

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