List Money That Left Your Accounts

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

Annotations already cover the safe read-only profile, but the description adds substantive behavior beyond them: transfers are matched over the whole scope before any range filter, so a transfer whose credit falls outside the range is never an outflow; amounts are cumulative per currency, never a balance; 'unknown' entries are never merged; and 'mayBeOwnAccount' pairs are listed apart with no total. This is real operating semantics an agent cannot get from 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?

Almost every clause is load-bearing (the destination-kind taxonomy and matching rules are needed to interpret results), but the content is delivered as one enormous run-on paragraph with nested quotes and no structure, so the most important usage guidance appears mid-paragraph rather than front-loaded. Informative but hard to scan.

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?

There is no output schema, so the description must explain the return shape, and it largely does: destination kinds with their follow-up actions, cumulative per-currency amounts, and the separate mayBeOwnAccount bucket. It stops short of fully specifying the response structure (ordering, grouping, counts), but is nearly complete for a tool of this complexity.

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 coverage is 100%, so the baseline would be 3, but the description adds meaning the schema does not: dateRange is inclusive YYYY-MM-DD, and the two date-range locations are not equivalent because a scope date range also narrows what gets matched, so dateRange is preferred. That is a genuine semantic distinction beyond the schema text.

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 opening clause states a concrete verb+resource ('Every debit that left your accounts') and explicitly carves out what it is not: not a confirmed transfer between one's own accounts and not a fee. It also distinguishes itself from siblings by forbidding the list_transactions summation route, though the core purpose is buried inside a dense enumeration of destination kinds rather than stated cleanly up front.

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?

Gives an explicit use case ('THE way to answer "did money disappear from my accounts, and where do I look next"'), an explicit anti-pattern ('never answer it by summing list_transactions rows'), and a concrete scenario for the dateRange parameter (a separation date). Alternatives and when-nots are both named, leaving little to inference.

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