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

readOnlyHint, destructiveHint=false, and openWorldHint=false already cover the safety profile, so the description only needs to add context — but "withdrawals stay in the app" is unclear and could be read as implying this tool touches withdrawals, which muddies rather than clarifies the read-only nature. It says nothing about what the returned balance represents, currency, or freshness. Not a direct contradiction, but the added sentence subtracts value.

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?

It is short, but the opening fragment is grammatically incomplete and not front-loaded with a verb, and the trailing clause about withdrawals is ambiguous enough that it does not earn its place. Two sentences with one clear idea and one confusing one.

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?

With no output schema, the description carries the burden of explaining the return value, and it only partially does — "available" and "to receive" are named but never defined, and no currency, timestamp, or shape is given. Safety is covered by annotations, so the remaining gap is the output explanation.

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?

The tool takes zero parameters, which is the baseline-4 case; the description correctly implies no scoping inputs are needed. There is no parameter ambiguity to resolve.

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?

"Balance available and to receive in the trainer's wallet" identifies the resource (wallet balance, split into available and pending) but is a sentence fragment with no verb, and it gives no signal to distinguish it from financial siblings like get_statement or get_monthly_closing. The gist is inferable, but the agent must guess at the boundaries.

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?

There is no statement of when to call this versus get_statement, get_monthly_closing, or list_payments. The only second sentence ("withdrawals stay in the app") is not usage guidance and does not tell the agent under what circumstances to reach for this tool.

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