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

Annotations already establish this is a safe, read-only, non-destructive call, so the bar is lower. The description does add useful non-obvious context — paper-dollar units, carry-over semantics, the DEPRECATED status of season_start_dollars — plus a directive to surface recently_settled to the person, which is a genuine behavioral instruction not derivable from annotations or schema.

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?

It is short and dense, but the structure is a semicolon-separated list of return fields rather than a front-loaded purpose-then-detail shape. The most important information (that this retrieves the account balance) is never stated at all, so brevity here reflects omission rather than economy.

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?

An output schema exists, so the description carrying the full burden of explaining return fields is partly redundant, yet its field notes and deprecation warning are still useful. What is missing is the framing sentence that tells the agent this is the balance-retrieval tool and when to call it; for a simple zero-parameter read that gap is survivable but real.

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 takes zero parameters, so per the rubric the baseline is 4. There is nothing for the description to compensate for and no input contract that could be misinterpreted.

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 evokes the resource — the account balance in paper dollars — but never states a verb or a purpose sentence; it opens mid-thought with 'The account in paper dollars, carried over.' The tool is distinguishable from siblings like get_positions or get_orders by virtue of its name, but the prose itself reads as field documentation rather than a statement of what the tool does.

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 when-to-use guidance, no mention of prerequisites, and no reference to any alternative sibling tool. The only quasi-instructional content is 'tell the person' about recently_settled, which is about presentation, not about when to invoke this tool versus another.

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