expenses_outstanding

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

With no annotations, the description carries the full burden. It clearly states that only charges with at least one confirmed reimbursement are counted, and transparently explains the data limitation that excludes unpaid charges. This provides concrete behavioral context beyond the tool name.

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?

Two well-structured sentences: the first immediately states the purpose, and the second explains the filtering rule. Every clause adds value without redundancy or wasted words.

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, no-output-schema tool, the description provides sufficient context: it tells the agent what data is returned (charges owed) and the rationale for exclusions. The only minor ambiguity is whether the output is a list or a sum, but the phrase 'charges' implies a list. An agent can confidently invoke this tool.

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 has zero parameters, so the description correctly adds nothing about them. Per the rubric, a zero-parameter tool receives a baseline 4, and the description appropriately avoids unnecessary parameter-related information.

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 states the tool lists charges still owed to the user, and clarifies the specific subset (shared charges with confirmed reimbursement) by explaining the exclusion of ordinary purchases. It gives a clear purpose but does not explicitly name sibling tools for other expense views.

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 implies when to use this tool (to see outstanding shared charges) and explains why certain charges are excluded due to data limitations. However, it does not mention alternative tools or provide explicit when-not-to-use scenarios beyond the exclusion logic.

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