check_balance

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

With no annotations, the description carries the burden of behavioral disclosure. 'Check' strongly implies a non-destructive read, and 'Requires a configured API key' reveals the authentication expectation. It does not describe the response format or rate limits, but for a zero-parameter check this is reasonably transparent.

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?

The description is two short sentences with no filler or redundant detail. The primary purpose is front-loaded, followed immediately by the operational prerequisite. Each phrase contributes distinct information, making it easy for an agent to parse.

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 parameterless read operation with no output schema, the description is largely complete: it states what is checked and what is required. The only real gap is not clarifying the relationship with the sibling get_pricing, which the overlapping 'pricing' term makes somewhat ambiguous.

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 has zero parameters and 100% schema description coverage, so there is no input ambiguity. The description adds value by clarifying what data is returned: credit balance, available hours, and pricing. This matches the baseline for parameterless tools and provides useful semantics beyond the empty schema.

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 a concrete verb ('check') and precise resources: Script API credit balance, available hours, and pricing. It is clearly a read-operation tool. It loses the top score because 'pricing' likely overlaps with the sibling get_pricing, and the description does not differentiate them.

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 description supplies one practical prerequisite: a configured API key. That gives some context about when the operation is executable. It does not explicitly state when to prefer this tool over get_pricing or other information tools, so selection among alternatives is left to inference.

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