Get a dynamic residential proxy connection string

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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, and the description is consistent with them. On top of that it discloses non-obvious behavior: credential reuse when a match exists, free creation, and that traffic is billed from a prepaid pool only when used. It omits rotation/expiry behavior of the returned URL.

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 with zero filler, front-loading the return value and then the reuse/create semantics. Every clause carries information an agent would otherwise have to guess.

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 correctly identifies the return value as a proxy URL, which covers the essentials. However, for a 6-parameter tool with 17% schema coverage, the budget/premium traffic distinction and protocol selection go unexplained, and nothing is said about how long a returned credential stays valid.

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 description coverage is only 17%, with country being the lone documented parameter, so the description must compensate. It adds real meaning for create_if_missing and implicitly covers state/city scoping, but says nothing about line (budget vs premium) or protocol (http vs socks5), which are meaningful choices affecting cost and client compatibility.

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 a specific verb and resource: return a ready-to-use rotating residential proxy URL scoped to a country (optionally state/city). That is clearly distinguishable from list_countries, list_regions, and get_account_usage. It stops short of explicitly contrasting with list_my_proxies, which is the sibling an agent might confuse it with.

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 clear operating context: reuse an existing matching proxy by default, and set create_if_missing=true only when none exists. It does not name any alternative tool or state when-not-to-use it, so it lands at 4 rather than 5.

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