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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description does not add behavioral details such as authentication requirements, output shape, or whether the family list is static or account-dependent; it mainly reinforces that this is a listing operation.

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?

The description is two short sentences with no wasted text. The primary purpose is front-loaded, followed immediately by the useful disambiguation.

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 simple read-only list tool with an output schema and annotation coverage, the description is nearly complete: it states what is listed and what alternative to use for name lookup. The remaining gap is the unexplained optional connection_context parameter, which is a modest omission given the tool's low complexity.

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 schema documents one optional connection_context parameter only by type and regex pattern, with no textual description. The tool description does not mention connection_context at all, so it does not compensate for the 0% schema description coverage, leaving the parameter's meaning unexplained.

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 a specific verb and resource: list supported deep-analysis families. It also distinguishes itself from the name-lookup sibling, but it does not clarify how it relates to the other deep-analysis tools such as google_ads_deep_analysis_query or google_ads_deep_analysis_export.

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?

It explicitly states what the tool does not do and names the correct alternative: use entities_lookup_by_name to find an ad, campaign, or creative by name. This gives clear when-not guidance, though it does not explain when to use this list versus the sibling deep-analysis query/export tools.

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