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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with 'No writes or access grants'. It adds a genuine behavioral trait beyond the annotations: restricted services require fresh server-verified access and otherwise refuse, which tells the agent to expect an auth-related refusal path.

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?

Three short sentences with no filler, and the read-only scope is front-loaded. However, the middle sentence is dense and cryptic, and space spent on 'bounded native' would have been better spent on the query body.

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?

An output schema exists, so return values need not be explained. But for a tool whose core input is a nested body with a constrained enum and a free-text query, the description says nothing about how to construct that payload or what the insight covers — a real gap for a 3-parameter, nested-schema tool.

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 only 33% — only customer_id is described in the schema, while the nested body (dimensions enum, query_text) and connection_context are undocumented. The description adds no meaning for any of the three parameters, leaving the agent to infer what a dimensions/query_text payload should look like.

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?

It states a verb (read) and a resource (audience_attributes insight), which is enough to know it is a read of audience attribute data. But modifiers like 'bounded' and 'native insight' are internal jargon, and nothing distinguishes it from siblings such as google_ads_audience_dates or the insights_query_* family.

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 statement of when to pick this tool over google_ads_audience_dates or the insights tools, and no mention of what the body query shape is for. The only guidance is an access precondition ('restricted services require fresh server-verified access'), which is a prerequisite, not a usage rule.

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