buy

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

With no annotations, the description takes on the burden of behavioral transparency. It reveals that limit orders may be blocked if the symbol is not allow-listed, and that cashQty is market-only. This is helpful disclosure. It does not discuss fees, partial fills, or order lifecycle.

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 concise, well-structured with line breaks, and every sentence provides necessary information without redundancy. It is easy to scan and understand.

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?

Despite having no output schema and no annotations, the description covers the main input constraints and a behavioral nuance. Lacks prerequisites (e.g., account funding) and details on order execution outcomes, but for a buy tool with 4 parameters, it is fairly complete.

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 coverage is 0%, so the description must explain parameters. It clarifies the mutual exclusivity of cash_amount and quantity, the role of limit_price, and that cash_amount represents US dollars. This adds significant value beyond the schema.

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 clearly states the tool is for buying stocks or fractional shares. The verb 'buy' plus the parameter explanation makes the purpose unambiguous. It distinguishes from siblings like 'sell' implicitly.

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 provides clear guidance on when to use cash_amount vs quantity, and when to include limit_price for limit orders. It also explains a behavioral nuance about limit orders. However, it does not explicitly contrast with related order types like stop_order or trailing_stop.

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