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

The readOnlyHint annotation already establishes that this is a safe read operation. The description adds useful context—version, API endpoint, wildcard filtering, and the from/to requirement for income statement accounts—but it does not describe the response format, grouping, pagination, or default behavior beyond what the schema provides.

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 four short sentences and front-loads the purpose before usage details. Every sentence carries useful information: the resource, wildcard syntax, a conditional date requirement, and the underlying API endpoint.

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?

All eight parameters are fully documented in the schema, and the description covers the key invocation constraints. Because there is no output schema, the description could say more about the returned balance structure, but it is sufficient for an agent to call 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 baseline is 3. The description adds a meaningful cross-parameter rule that income statement accounts need from and to, plus a wildcard example for accno, which goes beyond the individual parameter descriptions.

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 and resource: 'Get account balances (trial balance, version 2).' That is clearly distinct from sibling tools that list transactions, customers, invoices, projects, or charts, so an agent can identify the right tool without opening the schema.

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?

It gives concrete usage guidance for filtering ('Use x as a wildcard in accno') and a conditional requirement ('Income statement accounts need from and to'). It does not explicitly say when to prefer this over alternatives such as list_account_transactions, but the report-oriented context is clear.

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