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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds 'Does NOT modify any data' and lists the returned metrics (total clicks, top countries, devices, referrers), providing useful context beyond the annotations.

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 concise sentences: first states purpose, second enumerates return data, third confirms non-destructiveness. No fluff.

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?

The description covers what the tool does, what it returns, and its safety profile. Combined with rich schema annotations, it is well-specified for an agent. It doesn't mention response_format's effect on output structure, but that's in the schema.

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 0% — the tool description mentions no parameters. The schema itself describes 'period' and 'response_format' with enums and defaults, but the description adds no additional meaning or guidance for parameter selection.

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 clearly states the tool aggregates click analytics across all smart links with a specific verb+resource+scope. It says 'Get aggregate click analytics across all your smart links' and lists returned metrics, distinguishing it from sibling tools like get_smart_link_stats.

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 description explicitly frames the tool as account-wide aggregate analytics, implying use when high-level trends across all links are needed. However, it doesn't explicitly name alternative tools or state when not to use it.

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