Get balance

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

Annotations already disclose readOnlyHint=true and openWorldHint=true, so the safety profile is established. The description adds context beyond annotations by clarifying that the balance is current and represents spendable funds on numbers, which is helpful. It does not contradict any annotation.

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, front-loaded sentence with a useful parenthetical clarification. Every word contributes meaning, and there is no repetition of the title or schema fields.

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?

For a parameterless, read-only tool with no output schema, the description fully covers what an agent needs: what the tool returns and what the value represents. No further behavioral or return-format details are necessary 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?

The input schema has zero parameters and schema coverage is 100%, so there is no parameter information for the description to add. A baseline of 4 is appropriate when the schema carries no parameter burden.

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 ('Return') and names the exact resource ('reseller account's current balance'), clearly distinguishing it from siblings like get_number, check_order, and list_services. The parenthetical 'what you can spend on numbers' further removes any ambiguity about the meaning of the balance.

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 phrase 'what you can spend on numbers' implies when this tool should be used: before spending or ordering, to confirm available funds. No sibling tool overlaps with balance retrieval, so explicit exclusion language is unnecessary, but the description could still state the usage context more directly.

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