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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description still adds real value beyond them: the setup prerequisite for traffic tracking and the fact that data is 'live' rather than historical.

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?

Front-loaded with purpose, then clean 'Views' and 'Args' sections; each line maps to a distinct parameter or mode. Slightly redundant to restate defaults/ranges already in the schema, but no sentence is wasted.

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?

For a read-only analytics tool with no output schema, the description covers purpose, prerequisite, view semantics, and parameter defaults adequately. The remaining gaps — what each view actually returns and how user_intent is used — are minor.

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 25%, so the description must carry the load, and it does for three of four params: brand_id (required), view default/meaning, and days default plus 1-365 range. It omits any mention of user_intent, leaving that one parameter documented only by the schema.

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?

Opens with a specific verb+resource ('Get live traffic data for a brand's website') and narrows scope to AI-search-engine referrals, visitor counts, sources and trends. An agent can distinguish this from crawler siblings like get_crawler_live or get_search_performance, though the description never names a sibling to sharpen that contrast.

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?

It gives the prerequisite ('Requires traffic tracking to be set up') and explains the three view modes, which implicitly steers selection. However, there is no explicit 'use this instead of X when...' routing against the many sibling report/analytics tools, so usage is only implied.

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