add_expense

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states that a new expense entry is added, which implies a write operation, but it does not disclose permissions, idempotency, duplicate handling, validation behavior, or what the response will contain. This is thinner than expected for a mutation tool.

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: two short sentences with no wasted words. However, the second sentence largely repeats a constraint already present in the schema pattern, and the overall terseness contributes to the missing parameter guidance.

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?

With no annotations, no output schema, and no schema descriptions, the description leaves important context uncovered: valid categories, amount meaning, expected response, and error behavior. It is minimally viable but not complete enough for an agent to invoke the tool with full confidence.

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 0%, and the description only clarifies the date format, which the schema's regex already encodes. It does not explain whether category must match an existing category, what amount represents, or that description is optional. The parameter semantics are mostly left to the agent's inference from names and schema types.

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 operation ('Add') and the resource ('a new expense entry'), so its purpose is unambiguous. It is naturally distinguishable from sibling tools like list_expenses and delete_expense, though it does not explicitly name or contrast 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?

The intended use is implied by the phrase 'Add a new expense entry,' but the description provides no explicit guidance about when to prefer this tool over alternatives or any caveats. There are no exclusions or alternative tool references, leaving the agent to infer the appropriate context.

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