Get Spending Trends

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

Annotations indicate read-only, idempotent, and non-destructive behavior. The description adds substantial value by disclosing that the in-progress month is included as partial but excluded from trends, and that trend fields are null when fewer than two complete months exist. This goes beyond annotations and prevents misinterpretation.

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: the first efficiently states the tool's purpose and functionality, and the second clarifies important edge-case behaviors. Every sentence adds value without redundancy or fluff.

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 tool with 5 optional parameters and no output schema, the description covers time series behavior, grouping, trend detection, handling of the current month, and null-trend conditions. It provides sufficient context for an agent to understand what the tool does and its data requirements.

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 mentions grouping by category, payee, or category_group, which overlaps with the schema's enum for group_by. It adds minimal new semantic information beyond what the schema provides, meriting the baseline score of 3.

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 provides 'multi-month spending time series with trend detection' and specifies grouping options, distinguishing it from siblings like get_spending_analysis. The verb 'get' and resource 'spending trends' are specific and unambiguous.

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 trend analysis over time but does not explicitly state when to use this tool versus siblings like get_spending_analysis. It lacks when-not-to-use guidance and does not mention alternatives, though it does provide important context about the current month and data requirements.

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