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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so 'Read only' merely repeats structured data. The description adds no behavioral context such as whether the balance is live or settled, what currency is used, or whether any permissions are required.

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 very short and front-loads the purpose in the first sentence. The second sentence, 'Read only,' does not earn its place because it duplicates the readOnlyHint annotation, but the overall structure remains efficient.

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 zero-parameter getter with no output schema, the description is minimally adequate: it says what balance is returned. However, the crowded sibling set includes get_balance and get_digital_account_statement, and the description gives no clue about which one an agent should choose in a given situation.

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 the schema coverage is 100%, so there is no parameter semantics burden on the description. Baseline 4 applies for a no-parameter tool.

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 names a specific resource and attribute: the balance of the digital account. It is clear what the tool returns, but it does not distinguish itself from close siblings such as get_balance, get_digital_account_status, or get_digital_account_statement.

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?

There is no guidance on when to use this tool versus alternatives. The only extra sentence, 'Read only,' is a safety property rather than a usage condition, and an agent facing siblings like get_balance must infer the distinction on its own.

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