Get cash flow

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the agent knows this is a safe read operation. The description adds one useful behavioral nuance—the default current-month scope when dates are omitted. It does not add excessive detail, which is appropriate given the strong annotation coverage.

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?

Single sentence, front-loaded with the core output and grouping model, followed by a compact usage note. No filler or repetition; all content 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?

With only two optional inputs and an output schema present, the description covers the essential invoke semantics: what is returned, how it is grouped, and how to request the current month. Nothing needed for daily invocation is missing.

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 descriptions for both parameters only provide 'Date in YYYY-MM-DD format,' with 100% coverage, so the baseline is 3. The description adds semantic value by clarifying the default behavior when both are omitted (current month) and implying a date range when provided, which the schema does not communicate.

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 states a specific verb and resource: 'Get income and expense aggregates grouped by category, category group, and merchant.' This clearly differentiates it from sibling tools like get_cashflow_summary (which implies a summarized view) and get_transactions (which returns raw transactions). An agent immediately knows what object and grouping it will receive.

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 offers parameter usage guidance ('Omit both dates for the current month') but no explicit instruction on when to select this tool versus alternatives such as get_cashflow_summary or get_transactions. It lacks a when-to-use or when-not-to-use statement, leaving tool selection to inference.

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