Accounts Get Historical Balances

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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false. The description adds no behavioral context beyond the annotations; it merely restates the operation and does not mention scoping, return shape, or any side effects.

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?

'Get historical balances.' is very short and front-loaded, but it is under-specification rather than effective conciseness. It restates the tool name and does not earn its place by adding useful information.

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 tool with four parameters, a nested filter object, and no output schema, a single generic sentence is insufficient. It leaves unclear what historical balances are, how balance_date affects results, what filters do, and what the agent should expect in return.

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 50%; fields and output_mode have descriptions, but balance_date and filters are only named. The description does not compensate by clarifying the date format, filter semantics, or how balances are scoped.

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 historical balances. It is reasonably clear about the operation, though it does not differentiate from sibling tools like accounts_get_account_history or mention that balances are tied to a specific date.

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?

No guidance is provided about when to use this tool versus alternatives. There are no exclusions, prerequisites, or comparisons with the many sibling account and report tools.

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