queryBalance

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

The description adds useful behavioral context beyond the readOnlyHint and openWorldHint annotations by explaining the default accountCategory, the effect of omitting currency, and the meaning of the returned balance fields. There is no contradiction with the annotations.

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 well organized into short labeled sections for purpose, query parameters, balance information, and use cases. It front-loads the main purpose and avoids significant filler, though the use-case list is slightly redundant with the stated purpose.

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 read-only optional-parameter query with no output schema, the description provides the essential information: accepted categories, default behavior, currency omission semantics, and the three returned balance fields. An agent has enough context to invoke it correctly.

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%, so the description carries the parameter documentation burden. It explains accountCategory as fiat/crypto with a default and adds the important 'omit to return all balances' semantics for currency, compensating for the bare 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 has a specific verb and resource: 'Query fiat or crypto account balances,' and it clarifies the account categories and the returned balance fields. It is clear on its own, but it does not explicitly distinguish itself from balance-related siblings such as getWalletBalance or accountCoinBalanceQuery.

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 'Use Cases' section provides concrete contexts for when to call this tool: displaying available balance before trading, validating sufficient funds before quote application, and showing a balance breakdown to users. This is clear contextual guidance, though it does not mention alternatives or when not to use it.

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