buying_power

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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds a genuine data-semantics detail beyond the annotations: the figure is cash-based and excludes unsettled (미수) amounts, which affects how an agent should interpret the number. It says nothing about freshness, per-account scoping, or the effect of the currency switch, so it is only a partial addition.

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?

A single short sentence with no filler, and the key qualifier (cash basis, margin excluded) is placed up front. It is terse to the point of under-specification, but nothing it does say is wasted.

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?

Because an output schema exists, return values need not be explained, and the annotations carry the read-only safety profile. Still, for a financial query with a currency switch and multiple sibling account tools, the description omits how currency selection affects the result and when this tool is the right one to call.

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 0%, and the description never mentions the single 'currency' parameter, its USD/KRW enum, or the USD default. With low coverage, the description is expected to compensate for what the schema lacks, and here it does not.

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 — the cash-based buying power amount — and adds a scope qualifier that excludes margin/unsettled funds (미수 제외). That is a clear, distinguishing definition of what is returned. It does not, however, differentiate itself from siblings such as holdings or trading_status, which an agent could reasonably confuse with it.

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 contains no statement of when to call this tool, no prerequisites (e.g. account context), and no mention of alternatives such as preview_order or holdings. The likely use case — checking available cash before placing an order — has to be inferred entirely by the agent.

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