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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered; the description's "Read" merely restates the readOnly hint. It adds nothing about date-range semantics, attribution behavior, or response shape beyond what annotations and the output schema already provide.

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?

Four words is under-specification rather than conciseness; the single phrase is front-loaded but carries almost no load. Nothing here is wasted, but the brevity leaves the agent without the guidance the tool needs.

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 described, but for a 6-parameter analytics read the definition omits all parameter meaning, any usage context, and any distinction from the many sibling read tools. The description is not complete enough for reliable selection or invocation.

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?

Six parameters with 0% schema description coverage (date_from, date_to, attribution, product_ref, product_name, connection_context) and the description provides zero parameter information. It does not explain the date format, the accepted attribution values, whether product_ref or product_name is preferred, or what the connection_context pattern refers to.

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?

"Read per-ad funnel values" gives a verb plus resource, but it is close to a restatement of the name (get/read + funnel values) and the key term "funnel values" is never defined. The only added information is the "per-ad" granularity, so the agent cannot tell what metric family this returns versus siblings like products_get_actions or products_get_health.

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 indication of when to use this tool versus products_get_actions, products_get_health, insights_read_breakdowns, or products_save_funnel_events. With all 6 parameters optional, the description also gives no hint about which combination produces a meaningful call.

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