Budget Set Budget Category Variability

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

Annotations already convey that this is mutating (readOnlyHint=false) and non-idempotent. The description adds that it 'may create or update Monarch data,' which gives some context about the side effect, but it does not explain overwrite behavior, consequences for existing budget settings, or any result details.

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 concise and front-loaded with the core action. The second sentence about creating or updating Monarch data is somewhat generic but adds a minimal side-effect note; overall there is no unnecessary 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 mutating tool with two undocumented required params and no output schema, the description is too sparse. It lacks usage guidance, parameter semantics, and any explanation of return behavior or output modes, leaving too much for the agent to infer.

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 two required parameters, category_id and variability, have no descriptions. The tool description does not explain what category_id refers to or the meaning/effect of the fixed, flexible, and non_monthly variability values, so the agent must rely on parameter names and enums.

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 action and target resource: 'Set budget category variability.' This distinguishes it from sibling tools like budget_set_budget_group_variability, though it does not define what 'variability' means or list possible values.

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 guidance on when to use this tool versus alternatives such as budget_set_budget_group_variability or budget_set_budget_category_rollover. The description does not mention preconditions, scope, or scenarios where this tool is the appropriate choice.

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