Summarize Expenses

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

No annotations are provided, so the description carries the burden. It clearly states the aggregation behavior and grouping options, but doesn't disclose whether the result includes totals, counts, or both, or whether the output is a flat list or nested structure. The output schema exists and may cover this, but the description itself doesn't add behavioral context beyond the grouping dimensions.

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?

Two sentences with no filler. The core action and the key options are front-loaded. Every word 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?

For an aggregation tool with a 100% schema-covered parameter set and an output schema present, the description is largely complete. It could mention whether the aggregation includes all categories by default or requires explicit selection, but the schema's default for group_by and the optional category parameter cover most of that. The output schema likely explains the return shape.

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 schema already documents all parameters. The description adds the grouping dimension context ('Group by category, subcategory, month, or day') which reinforces the group_by parameter, but doesn't add 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 uses a specific verb ('Aggregate') and resource ('spending over a date range'), and explicitly lists grouping dimensions. It clearly distinguishes this from sibling tools like list_expenses (which would list individual expenses) and get_category_breakdown (which is category-specific).

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 you need aggregated spending totals over a date range, rather than individual expense records. It doesn't explicitly name alternatives or exclusions, but the grouping options and aggregation language make the use case clear. Sibling names like list_expenses and get_category_breakdown provide additional context.

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