check_balance

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

With no annotations, the description covers the return values ('wallet, credits_remaining, and pack info') and implies a read-only operation, adding useful transparency beyond the bare minimum.

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 a single concise sentence that packs the purpose, action, and output details without any wasted words, fitting the tool's simplicity.

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 is adequate for a simple balance check with one parameter, but it lacks details on token validity, error handling, or auth requirements, which could be important for correct invocation.

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 100% (parameter has description), and the tool description adds context about the output fields, which helps the agent understand the parameter's effect even without an output 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 clearly states the action 'Check remaining credits' and the target resource 'prepaid credit token', distinguishing it from sibling data-fetching tools like get_signal or get_pricing.

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?

No explicit when-to-use or alternatives are mentioned, but the tool's purpose is narrowly defined for credit balance checking, which is implied. Siblings are sufficiently different, reducing ambiguity.

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