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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavioral context: one-off pricing with no subscription and a 24-48h turnaround (24h priority for Rank 10), which tells the agent what commercial and timing facts the response conveys.

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 the price table, then the usage trigger, then the parameter — a sensible order with no filler. The first sentence is dense and comma-heavy, but every clause carries a price or timing fact an agent would otherwise have to fetch.

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 no output schema, the description must convey what comes back, and it does by inlining the pack names, prices and turnaround times. The only gap is that it doesn't say whether the payload is narrative text or structured tiers, which matters mildly for a pricing-only tool.

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 there is only one parameter, so the description's 'Pass language en or es' merely restates the enum in the schema. It adds no guidance on defaulting or what happens if omitted, so it neither helps nor hurts beyond baseline.

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 names a specific resource (Creator Validator pack prices) and enumerates the actual tiers and prices, so an agent knows exactly what it gets back. It implicitly covers the 'Find + Vet' offering that maps to the sibling book_find_and_vet but never names that sibling, so differentiation is inferred rather than stated.

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 someone asks what creator or influencer vetting costs or how long it takes' gives a clear triggering condition for the agent. It does not, however, state when to prefer book_find_and_vet or start_order instead — the booking siblings are only hinted at through the pricing mention.

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