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

With no annotations provided, the description carries the behavioral disclosure burden. It clarifies that the balance is operator-owned funding rather than a patron balance, explains the consequence of a zero balance, and directs the operator to purchase_credits as the remedy. The read-only nature is implied by 'Check,' and the output schema covers return details.

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 tight and front-loaded with the core action, then adds meaningful context in short sentences. Every sentence earns its place: what the balance is, how it is used, what happens at zero, and a clarifying exclusion from patron balance.

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 is complete. It covers the purpose, the meaning of the returned value, the zero-balance failure mode, the required remediation, and the distinction from patron balances. No critical operational information is missing.

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 100%, so there is no parameter documentation burden. The baseline of 4 applies; the description adds useful conceptual context even though no parameters exist to explain.

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 states a specific verb ('Check') and a specific resource ('this operator's tax balance at the Authority'), then defines the balance's purpose: sats available for certifying patron credit purchases. It also distinguishes itself from the sibling check_balance by emphasizing that this is the operator's own funding, not a patron 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 description gives clear context for when this tool matters: checking funds available for certifying patron top-ups, and notes that when the balance reaches zero, the operator must call purchase_credits. It does not explicitly enumerate sibling alternatives, but the context makes the appropriate use clear.

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