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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without the description. The description adds real value by explaining what a returned entry contains and defining nextRunDate as 'the next day a record will be added for it', but says nothing about result size, ordering, or whether inactive entries are included.

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?

One front-loaded sentence with no preamble or filler, and the resource identity comes before the field list. The trailing field enumeration and the nextRunDate gloss make it a long run-on, but every clause carries information.

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 zero-parameter, non-destructive read tool with a full annotation set and an output schema, this is nearly complete. The enumeration of returned fields is arguably redundant with the output schema, but the nextRunDate definition and the active-flag mention remove genuine ambiguity.

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 tool takes zero parameters, so there is no parameter semantics to compensate for; the schema is empty and requires no elaboration. The description instead spends its words on the response shape, which is the only thing an agent could be uncertain about here.

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 gives a specific verb ('Lists') and resource ('the user's recurring expenses'), illustrated with recognizable examples (rent, subscriptions). It is clearly distinct from list_records and the create/update/delete_recurring_expense siblings by name, though it never explicitly contrasts itself with them.

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?

There is no when-to-use, when-not-to-use, or alternative-tool guidance anywhere in the description. The agent must infer from the tool name alone that this is the read path for recurring-expense configurations versus list_records or get_record.

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