Ads reach products

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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=true, so the safety profile is covered structurally. The description adds nothing beyond that—no note on what 'plannable' means, whether results are filtered or gated by account eligibility, or any latency/scope caveats.

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 compact sentence with the key qualifiers (video/display, per location) front-loaded and no filler. It is efficient, though its brevity tips into under-specification rather than genuine crispness.

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?

Because an output schema exists, return values need not be explained. Still, for a tool whose only input is an ambiguous location identifier, the definition should say how to obtain and format that ID and how the product list feeds ads.reach.forecast; neither is present.

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 single parameter location_id has 0% schema description coverage, so the description carries the burden. 'For a location' only weakly implies the parameter is a location identifier; it does not say whether this is a Google Ads location criterion ID, a canonical geo ID, or a free-text name, which is a meaningful gap for a 100%-required param.

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 phrase 'plannable video/display products for a location' names a resource and a scope, so an agent can infer this returns a list of ad product types usable in Reach Planner. However, the verb is missing (it reads as a label, not an action) and nothing distinguishes it from adjacent siblings like ads.reach.locations or ads.reach.forecast.

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?

There is no explicit when-to-use guidance, no prerequisites, and no mention of the obvious alternatives (ads.reach.locations to resolve locations, ads.reach.forecast to project reach). The 'Reach Planner' prefix hints at a workflow but never states the call sequence.

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