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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety and locality profile is covered. The description's one added signal is that results come from a built-in table, which corroborates openWorldHint=false, but it offers no further behavioral context. With annotations carrying the burden, a 3 is appropriate.

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?

Two short sentences, with the usage trigger front-loaded and the implementation mechanism second. Nothing is redundant or padded.

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 no explanation, annotations cover the safety profile, and the sole parameter is fully documented. Nothing an agent needs in order to call this tool correctly is missing.

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 description coverage is 100% for the single required activity parameter, and the examples in the description (4K streaming, video calls, gaming) largely duplicate the schema's own example string. Baseline 3 applies since the schema does the heavy lifting and the description adds no new syntax or format guidance.

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: it looks up reference bandwidth requirements for a named activity from a built-in table. That static-table mechanism inherently separates it from siblings like run_speed_test (a live measurement) or calculate_data_budget (a computation), though it never names or contrasts those siblings explicitly.

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?

"Use when the user asks how much bandwidth an activity needs" gives clear trigger context, reinforced by concrete examples (video calls, 4K streaming, gaming). It stops short of stating when NOT to use it or pointing to alternatives such as run_speed_test for real measured speeds.

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