get_balance

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description earns credit by adding domain behavior the annotations cannot convey: the 1 credit = US$0.01 conversion and the fact that frozen credits are tied up by running tasks, which explains why the two figures may differ. It does not, however, note anything about rate limits or freshness.

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 core action leads while the explanatory detail about frozen credits follows. Every clause carries information.

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 an output schema present, the description need not explain return values, and it correctly stays brief for a zero-parameter read. The one omission is a pointer on how this relates to get_usage, which matters given the sibling set.

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, and the schema is fully specified with no fields to document. Baseline 4 applies since there is nothing for the description to clarify.

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 specific verb and resource: retrieve the account's available and frozen credits. The scope is precise and the credit unit is defined, so an agent knows exactly what it returns. It does not differentiate itself from the sibling get_usage, which is the one nearby tool 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?

There is no statement of when to call this versus get_usage, nor any prerequisites or exclusions. The only contextual cue is the explanation of frozen credits, which helps interpret the result but not decide when to invoke the tool.

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