get_credit_balance

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

No annotations are provided, so the description carries the full burden. It clearly implies a read-only status check and lists the information returned, but it does not explicitly state that checking does not consume credits or note any authentication requirements. Still, for a simple balance lookup, it provides adequate behavioral 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?

The description is two sentences and immediately states the purpose. The second sentence adds actionable guidance without any filler or repetition. It is front-loaded and every word earns its place.

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?

Despite lacking an output schema, the description thoroughly explains the return values (balance, limit, tier, reset time) and the practical use case. For a zero-parameter read-only tool, this is complete and leaves no major ambiguity.

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 the schema coverage is trivially 100%. The description adds value by explaining what kind of information the tool returns, which compensates for the absence of parameters. Per rubric, zero-parameter tools receive a baseline of 4.

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 uses a specific verb ('Check') with a clear resource (credit balance) and lists the exact data points returned: current balance, monthly limit, plan tier, and reset time. It is clearly distinct from sibling tools, none of which deal with credits or billing.

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 provides explicit guidance on when to use the tool: to verify sufficient credits before launching research or campaigns. It does not mention alternatives or exclusions, but since no sibling tool appears to cover credit info, this is clear enough.

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