Get account balance

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

Annotations already mark readOnlyHint and openWorldHint, and the description reinforces 'Read-only' while adding context about the 90-day auto-renewal window and the distinction between available and account balance. It does not disclose auth requirements, but the tool is simple and the annotations cover the safety profile, so this is more than adequate.

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 exactly two sentences: the first front-loads the primary purpose with concrete data fields, the second gives a practical usage tip. There is no wasted wording or unnecessary repetition.

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 an output schema, the description fully covers what it does, when to use it, and its read-only nature. The output schema handles return-value details, so no further explanation is needed.

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 tool has zero parameters and schema coverage is trivially 100%. The description explains what the result contains (available balance, account balance, auto-renewal funds), which is relevant even though parameter semantics are not needed. Baseline for 0 params is 4.

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 Namecheap account funds, listing specific components (available balance, account balance, 90-day auto-renewal fund requirement). It distinguishes itself from sibling tools that operate on domains or DNS records, making its unique purpose obvious.

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 explicitly advises to check this tool before register/renew/transfer, linking to a common failure mode ('order creation failed'). This provides clear when-to-use guidance; no alternatives are needed since no sibling tool offers account balance data.

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