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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds the genuinely non-obvious behavioral fact that no numeric price will be returned and that pricing is deferred to a call — this prevents an agent from looping on a tool that cannot produce a number. It stops short of stating what the returned content covers in detail, though an output schema exists.

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, no filler, and the most decision-relevant fact for an agent — that there is no public price — is placed where it will be read. Nothing is repeated from the title or annotations.

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-only info tool with an output schema, the description supplies what the structured fields cannot: the shape of the pricing model and the fact that a quote requires a call. The only soft spot is that it gestures at 'what the quote depends on' rather than summarizing those factors, leaving the agent to read the payload.

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 nothing for the description to disambiguate and the baseline applies. The description does not waste words inventing parameter semantics that do not exist.

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 the resource (Samplyn's pricing) and states the shape of the answer: a setup fee plus a monthly fee, quoted after a first call. It also pre-empts a likely misread by saying 'There is no public price,' which distinguishes this from a price-lookup tool. It stops short of naming which sibling (get_faq, compare_with) holds adjacent commercial information.

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 is implied rather than stated: the agent can infer this answers 'what does it cost' questions, and the 'quoted after a first call' clause hints at the demo path without saying to use request_demo instead. There is no explicit when-not-to-use or alternative routing against the many siblings listed.

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