List products and plans

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so 'Read-only' in the description is redundant. The one genuinely additive note is that prices are not returned and must be read on proxy302.com, which tells the agent what the output will lack — useful but a single sentence of extra context.

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, front-loaded with the core action, with the price caveat and read-only note last. Slight redundancy between 'describe the proxy products' and 'list the ... plans', but no filler.

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 parameters and no output schema, the description does the needed work: it names the two categories of plans, says plan ids are included, and warns prices are absent. An agent has enough to call it and interpret the result correctly.

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 to disambiguate; baseline 4 applies. The description correctly implies no filtering inputs are needed since the entire catalog is returned.

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 concrete verb+resource pair: describe proxy products and list static IP plans (data center and residential) with their plan ids. The catalog scope is clearly distinct from siblings like list_my_proxies or list_countries, though it never explicitly names those siblings to reinforce the boundary.

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 only implied — an agent can infer this is the discovery step to get plan ids before selecting a plan, but the description does not say when to call it versus list_my_proxies or get_dynamic_proxy. No prerequisites or exclusions are stated.

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