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

Annotations already declare readOnlyHint, idempotentHint, closed-world and non-destructive, so the safety profile is covered. The description adds a useful behavioral caveat beyond the schema – that no prices are returned and pricing flows go elsewhere – though it says nothing about shape beyond one-line summaries plus a page reference.

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 no filler. The content statement comes first and the pricing exclusion/routing second, so the reader gets the payoff immediately.

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 zero-parameter read tool with no output schema, the description conveys enough of the return contents (one-line summary plus page) and a key negative (no prices) to call it correctly. Minor gap: it doesn't indicate how the service set is ordered or whether the page is a URL or an identifier.

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?

The tool takes zero parameters, so there is no parameter semantics for the description to explain. Baseline 4 applies; the description is not obligated to add anything here.

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 the resource and return contents ("each service with a one-line summary and its page"), which makes the catalog-listing purpose identifiable alongside the name get_services. It lacks an explicit verb phrase ("list/return"), and it doesn't distinguish itself from fetch or search, but start_a_quote is contrasted for pricing.

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?

"Prices are not listed; every job gets a fixed, itemized quote through start_a_quote" explicitly routes the pricing question to a named sibling, which is real when-to-use guidance. It doesn't cover when to prefer this over fetch or search, so the routing is only partially complete.

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