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 adds that a live dashboard URL (stats_url) is returned, which is useful behavioral context, but says nothing about data freshness, latency, or what happens for a link with zero traffic.

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 sentences, front-loaded with the primary outcome and followed by the notable secondary return value. No filler and every clause carries information.

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?

With an output schema present and annotations covering the safety profile, the description needn't enumerate return fields, yet it does enough to tell the agent that both metrics and a shareable dashboard URL come back. Only minor gaps remain, such as noting the link must already exist and be owned by the caller.

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 both parameters are required, so the schema fully documents id and key (including their provenance). The description adds no syntax, format, or coupling details beyond the schema, so the baseline 3 applies.

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?

States a specific verb and resource ('see who opened one of your links') and enumerates exactly what is measured: views, visitors, countries, devices, referrers and agent reads. This is unambiguous and cannot be confused with siblings like delete_link or create_webhook.

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?

Usage context is implied by the purpose (call it when you want engagement data for an existing link), but there is no explicit when-to-use guidance, no prerequisites, and no named alternative. Adequate but with a clear gap.

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