List plan months

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds value beyond that by disclosing result ordering (newest first) and the specific content of the returned totals, which the agent cannot get from the annotations alone.

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 short sentences with the core operation and ordering front-loaded, followed by one sentence of usage context. No filler or repetition.

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?

An output schema exists, parameters are fully documented, ordering is stated, and the description names the metrics returned. What remains unstated is how pagination interacts with the 'newest first' ordering, a minor gap.

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% and both limit and offset are documented inline, including defaults. The description adds no pagination or parameter semantics beyond the schema, so baseline 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?

States a specific verb and resource ('List the plan's months with their totals') plus the ordering ('newest first'), so the operation is unambiguous. It does not explicitly name the singular sibling get_plan_month, so differentiation from that tool is left to be inferred from the name.

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?

'Use this for trends over time' gives a clear positive selection context and enumerates the specific trend dimensions (income, assigned, activity, Ready to Assign, age of money). It stops short of naming an alternative such as get_plan_month for a single month, so there is no exclusion guidance.

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