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

Despite strong annotations (readOnly, idempotent, non-destructive), the description adds meaningful behavior beyond them: investments use the 'last quote,' amounts are 'restated at today's rate,' and unconvertible items are explicitly listed. This gives the agent an accurate model of what the tool actually does with data, which annotations do not convey.

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 two tight sentences with no filler. The primary idea is front-loaded, the component breakdown is scannable, and the caveat about unconvertible items and per-currency exactness is placed at the end without bloating the message.

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 aggregation tool with a single optional parameter, an output schema, and strong safety annotations, the description covers the important operational details: valuation basis, scope of assets/liabilities, conversion behavior, and failure handling. An agent has enough context to call this tool correctly and interpret its purpose relative to siblings.

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%, so the single optional currency parameter is already documented in the schema. The description reinforces that the whole summary is expressed in one currency and restated at today's rate, but it does not add new parameter-specific meaning beyond what the schema provides. Baseline 3 is appropriate.

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 defines the tool as a consolidated net-worth snapshot, listing exactly which components are included: cash, investments, amounts owed, and amounts owing. It distinguishes this aggregate view from the many raw list/ledger siblings by emphasizing 'the whole picture in one currency.' The intent is unambiguous even though it relies on 'restated' and 'Lists' rather than a single imperative verb.

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 implies when to use this tool: when a consolidated multi-currency picture is needed. It also gives guidance to prefer other tools when exact per-currency figures are required: 'Per-currency figures stay exact in the other tools.' It does not name specific sibling tools like list_holdings or list_debts, but the routing signal is clear.

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