createPayee

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states that a payee is created and does not mention required plan_id semantics, validation rules, side effects, permission needs, or behavior around the 'last-used' and 'default' plan options.

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 a single clear sentence with no filler or repetition. It is front-loaded and easy to parse, though it is so brief that it sacrifices informative content in other dimensions.

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 and the input schema documents both required properties, which helps. However, the description lacks usage context, behavioral disclosure, and any differentiation from the many sibling create/update tools, making it insufficient for an agent to confidently select and invoke this tool correctly in context.

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 50%, and the description adds no parameter-level meaning beyond the schema. The plan_id 'last-used'/'default' semantics and the payee name maxLength constraint are already in the schema; the description does not help an agent understand the nested payee object or how plan_id relates to creation.

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 'Creates a new payee' uses a specific verb and resource, making the basic action clear. It implicitly contrasts with sibling updatePayee, though it does not mention the plan_id scoping or YNAB context that would fully distinguish it from other create operations.

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 gives no guidance on when to use this tool instead of alternatives like updatePayee or createCategory. The sibling list implies a CRUD context, but the description does not state any conditions, exclusions, or decision rules for selecting this tool.

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