get_balance

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

No annotations are provided, so the description must carry the burden of explaining behavior. The verb 'Retrieve' clearly signals a read-only operation, and 'current' indicates the balance is fetched live rather than from a cache. It does not mention authentication or rate limits, but for a simple read-only balance tool, the core behavioral traits are disclosed.

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, focused sentence with no filler. It front-loads the action ('Retrieve') and follows with the exact object and scope, making it easy to parse quickly.

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 tool is simple: one required parameter, no nested objects, no output schema. The description adequately conveys what is returned ('balance and payout details') and the source ('a courier'). It stops short of describing the exact response shape, but given the low complexity, this is complete enough for an agent to invoke the tool correctly.

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 description coverage is 100%, so the schema already fully documents the only parameter ('courier', including its enum values and description). The tool description adds no extra meaning beyond the schema, so the baseline score of 3 is appropriate.

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 ('Retrieve') and clearly identifies the resource: 'merchant account balance and payout details'. This distinguishes it immediately from sibling tools like create_parcel, track_parcel, and check_fraud_risk, which have obviously different purposes.

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 intended use is implied by the function name and description: call this when you need a merchant account balance or payout details for a courier. However, it does not explicitly state when not to use it or mention any alternative/companion tool, so usage guidance is present only by implication.

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