get_balance

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

Without annotations, the description should disclose behavioral traits. It describes what data is returned (balance, pending charges, etc.) but does not explicitly state that the tool is read-only, requires no special authentication, or has any rate limits. However, for a zero-parameter tool, the simplicity partially compensates.

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 front-loads the purpose and lists the specific data fields returned. No unnecessary words.

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?

Given the presence of an output schema (not shown), the description does not need to detail return format. It lists the key fields. However, it could improve by mentioning that this is the aggregate balance view, contrasting with siblings like get_charges_breakdown.

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?

There are no parameters, so the schema coverage is 100%. The description does not need to add parameter-level details. Baseline for no parameters is 4, and the description provides sufficient context about what the tool returns.

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 tool retrieves account balance, pending charges, credit limit, and available credit. It uses a specific verb ('Get') and resource ('account balance'), and differentiates from siblings like get_charges_breakdown which likely provides detailed charge information.

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 guidance on when to use this tool vs alternatives such as get_charges_breakdown or get_charges_summary. The description does not mention when to choose this over other balance-related tools.

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