add_expense

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

No annotations are present, so the description carries full burden. It only repeats the tool's name ('Add an expense') without disclosing side effects, validation rules, idempotency, or return behavior. For a write operation, this is insufficient.

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 sentence with no wasted words, but it is under-specified to the point of being nearly tautological. Conciseness should serve clarity, and here it sacrifices critical 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?

With 5 parameters, no output schema, and no annotations, the description fails to provide necessary context. It does not explain what constitutes a valid expense, how categories are structured, or what happens upon success/failure. The tool is too underspecified for reliable use.

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 schema has 5 parameters with 0% description coverage, and the description provides no information about parameter meanings, formats, or relationships. The tool name 'expense' plus schema types (e.g., number, string) are not enough for an agent to correctly populate fields like 'subcategory' or 'note'.

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 uses the specific verb 'Add' and identifies the resource 'expense', clearly indicating the primary action. It implicitly distinguishes from sibling tools like 'update_expenses' and 'delete_expenses' through the verb choice, but does not explicitly contrast 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?

No guidance is provided on when to use this tool versus alternatives. It does not mention prerequisites, common use cases, or exclude scenarios. With many expense-related sibling tools, some guidance is expected.

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