polygon_balance

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

With no annotations, the description carries the full burden. It discloses the pay-per-call cost and that a live USD conversion is involved, which is beyond trivial knowledge. It does not mention error behavior, network assumptions, or rate limits, but for a simple read query the disclosure is reasonable.

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?

A single, dense sentence conveys the core function and the cost. It is front-loaded with the purpose, and every word earns its place with 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?

The description covers the basic purpose and cost, and the return content is implied (balance + USD value). However, the unexplained 'fields' parameter and lack of any output schema details leave an agent guessing about optional behavior, making it minimally adequate rather than complete.

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 only 50% and the description adds no meaning for the 'fields' parameter at all. The only parameter mentioned implicitly is 'address', which the schema already describes. The description fails to compensate for the missing parameter documentation.

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 clearly states the resource ('native balance and live USD value') and scope ('any polygon address'). It is unambiguous enough to differentiate from polygon health, block, token, etc., though it does not name a specific sibling alternative as a contrast.

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?

The pay-per-call cost is noted, which is useful for deciding whether to call. However, there is no explicit when-to-use guidance or comparison with alternatives like base_balance or polygon_stables; usage is inferred primarily from the tool name.

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