Ads reach locations

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. Beyond that the description adds nothing: no scope (account, campaign, network), no indication of whether the location set is fixed or depends on targeting inputs, and no caching or latency context for an open-world call.

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?

A single short clause with no filler, and the key information (what the output is and what consumes it) is front-loaded. It is terse to the point of being telegraphic – the colon fragment is less readable than a plain sentence – but nothing is wasted.

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?

With an output schema present and rich annotations, the description does not need to explain return shape or safety, and it correctly points at the downstream tools. It is still short of complete because it never states what the returned locations are scoped to or what the caller is expected to do with them beyond passing IDs on.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; per the baseline for 0-param tools this scores a 4. The description does not misrepresent inputs, and the input schema is empty and complete.

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 names the resource ("plannable locations") and its role (IDs consumed by ads.reach.products / ads.reach.forecast), which does tie it to the right siblings. However, there is no verb at all – an agent must infer that this is a list/lookup call – and the fragment "Reach Planner:" is a label rather than a statement of what the tool returns.

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 only implied through the workflow hint that these IDs feed ads.reach.products / forecast, which is genuinely useful for sequencing. There is no explicit when-to-use statement, no note on whether prior setup is required, and no mention of alternatives or when not to call it.

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