Account cash and balance

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the safe read-only nature is known. The description adds value by listing exactly which cash breakdown items are returned and noting the currency caveat, though it doesn't describe the return format (no output schema exists).

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?

Three sentences, each with a distinct purpose: the first lists contents, the second gives usage guidance, and the third adds a currency caveat and cross-reference. It is front-loaded with the main verb and contains zero fluff.

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 zero-parameter, read-only tool with no output schema, the description provides complete context: what the tool does, what data it returns, when to use it, and a critical caveat about currency. No essential information is missing.

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?

There are zero parameters, so the baseline for parameter semantics is 4. The description doesn't need to explain parameters and doesn't attempt to; it appropriately focuses on output and usage.

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 returns the account's cash breakdown and enumerates specific components (free cash, total value, invested amount, etc.). It also distinguishes itself from siblings by mentioning t212_get_account_info for currency and by framing its use case directly.

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?

Explicit usage guidance is provided: 'Use this for any question about how much money is in the account or how it is performing overall.' It also points to an alternative tool for currency, giving clear when-to-use versus when-to-use-another-tool direction.

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