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

The annotations only indicate readOnlyHint=false, and the description's 'setting' wording is consistent with that. However, the description does not disclose that this is an overwrite of the existing cash balance, whether permissions are needed, or what other effects the operation may have; the only behavioral nuance ('not delta') lives in the parameter schema, not the description.

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 a single short sentence that states the operation and object with no filler. It is appropriately front-loaded and compact, though its terseness borders on under-specification.

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 write operation with four required parameters and no output schema, the description is minimal. It does not explain the semantic effect of 'set' (override vs. delta), when to use it, or what the agent should expect after invocation. The schema compensates partially, but the overall context remains incomplete.

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 75%, with broker, account, and amount already documented, including the important note that amount is the post-change balance rather than a delta. Currency is an enum. The description itself adds no parameter-level meaning, so the baseline of 3 applies.

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 uses a specific verb ('Ustawienie' – setting) and names the target resource ('saldo gotówki na rachunku' – cash balance on account), so the core action is clear. It does not explicitly differentiate itself from sibling mutation tools like modify_holdings or submit_portfolio_snapshot, but the cash-balance focus gives reasonable distinctness.

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 provides no guidance on when to use this tool versus alternatives such as submit_broker_transactions or modify_holdings. There is no mention of prerequisites, context, or situations where this tool should or should not be chosen.

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