get_balance

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

With no annotations provided, the description carries the full behavioral disclosure burden and does well: it labels the call as 'Read-only, free' and warns that values are 'a snapshot of this moment – the numbers move as operations run.' This conveys no side effects and the non-deterministic nature of the result, which is critical for an agent deciding whether to call it again. No contradiction with any annotations.

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 three sentences with no filler. The first sentence front-loads the core purpose, the second provides usage context and the snapshot caveat, and the third handles sibling differentiation. Every sentence earns its place, making it compact yet information-dense.

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 having no output schema or annotations, the description covers purpose, when to use it, behavioral caveats, and the specific data points returned. The tool is a zero-parameter read operation, so nothing needed is missing. The listed fields (remaining credit, free operations left, monthly cap, spend) are sufficient for agent decision-making.

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 input schema is empty (0 parameters), so the baseline is 4. The description adds context by specifying that the tool checks the 'currently configured' bigapi key, clarifying the implicit subject without requiring a parameter. Since there are no parameters, the description cannot add much more, but the existing added meaning is valuable.

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 opens with 'Check the bigapi key that is currently configured' and enumerates exactly what is read: remaining credit, free operations left, monthly cap, and spend. It explicitly differentiates from sibling get_access by stating it does not create keys, and from list-like tools by noting it does not list past operations. This is a precise verb+resource definition with clear sibling differentiation.

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 gives explicit intended triggers: 'Use it to confirm a key works, before a large batch, or when an operation reports a low balance.' It also tells the agent when not to use it by stating it does not create keys or list operations, effectively routing those needs to siblings like get_access. This is strong practical guidance beyond generic 'use this for balance.'

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