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

Annotations already declare readOnlyHint, openWorldHint, and destructiveHint=false. The description adds the SELECT-only constraint and single-account scope, but does not disclose result limits, pagination, error behavior, or what happens when account resolution is ambiguous.

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 definition is two tight sentences with no wasted wording. The core operation is front-loaded, and the main restriction follows immediately.

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 general GAQL escape-hatch tool, the description covers purpose, read-only behavior, SELECT-only restriction, and one-account scope. It is still thin on operational behavior such as row limits, pagination, and handling of account ambiguity, and there is no output schema to cover return semantics.

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 coverage is 100%, and the schema itself explains both the required GAQL SELECT statement and the optional account identifier. The description only broadly reinforces these semantics, adding no syntax or validation detail beyond the schema.

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: running a read-only Google Ads Query Language SELECT statement on one account. It also distinguishes the tool as a fallback for analysis not covered by other tools, which is important given the many dedicated Google Ads siblings.

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?

The phrase 'for analysis not covered by other tools' gives clear when-to-use guidance, and 'Only SELECT is allowed' sets a key restriction. It does not name specific alternative sibling tools, but the fallback intent is clear enough for selection.

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