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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It discloses the key filter of only counting FILLED payments and the date default behavior. It does not mention rate limits, auth requirements, or error handling, but for a read-only aggregate query, this is a reasonable amount of disclosure. A score of 3 reflects that it adds meaningful behavioral context but not exhaustive details.

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 sentences with no redundancy. The main action and the critical qualifier (FILLED only) are front-loaded, making it clear and scannable. 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?

Given that an output schema exists, the description need not explain return formats. It covers the core behavior (aggregated volume, date default, filtering) and the parameters are fully documented in the schema. It could add a note on timezone handling or what 'volume' sums, but these are minor gaps, so it is sufficiently complete for a straightforward read tool.

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 input schema already documents both parameters with 100% coverage, including the default for 'date' and the auto-discovery of 'externalPlatformId'. The description adds no additional semantic detail beyond what the schema already provides, 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 clearly states the tool returns total payment volume for a specified date, with breakdowns by network and currency, and explicitly notes it only counts FILLED payments. This is specific and distinguishes it from sibling tools like lookup_payment or search_payments, which likely return individual transaction details rather than aggregated volume.

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 usage for querying daily volume with an optional date, and mentions that it defaults to today. However, it does not explicitly state when to prefer this tool over alternatives such as get_payment_summary or get_unswept_balances, nor does it provide exclusions or prerequisites. Thus, the usage context is clear but not fully articulated.

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