Get account balance

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

Annotations declare readOnlyHint=true, so the safety profile is already covered. The description adds genuinely useful behavioral detail beyond that: the response carries two distinct balances (cleared = settled, effective = including pending), which prevents misreading the output. It does not cover error behavior for an unknown accountUid.

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?

Two sentences, no filler, front-loaded with the action and followed by the one detail an agent needs to interpret the result. Every sentence earns its place.

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?

The tool is a single-parameter read with an output schema that documents the return shape, so the description need not explain return values; its clarification of the two balance types covers the only ambiguity. Nothing required to invoke it correctly 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?

Schema description coverage is 100% for the single accountUid parameter, so baseline 3 applies. The description says 'a specific account' but adds no format or provenance guidance for the UID beyond what the schema provides.

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?

States a specific verb and resource ('Get the balance for a specific account') and immediately clarifies the scope of the returned data. It is trivially distinguishable from siblings like accounts_list or transactions_list, which cover different resources.

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?

Usage is implied rather than stated: an agent needing a balance for one account would pick this, but the description never says when to prefer it over accounts_list or transactions_list, nor any preconditions such as resolving an account UID first. Adequate but with a clear gap.

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