compare_loans

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

With no annotations, the description carries the burden of disclosing behavior. It states that the tool returns a 'backend JSON payload with comparison results or an error structure,' adding useful context about output and error handling. The verb 'Compare' naturally implies a non-mutating operation, which adds behavioral transparency.

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 well-structured, opening with a clear purpose statement followed by Args and Returns sections. Every sentence provides value without unnecessary padding.

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?

The description covers the main parameters, return type, and error structure. However, it does not enumerate possible values for calculation_method (e.g., 'reducing' vs. 'flat'), and the nested scenario structure could be more detailed. Given the tool's complexity and the presence of an output schema, this is a minor gap.

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 provides no descriptions for parameters, but the description compensates fully by explaining each parameter: scenarios is a list of dictionaries with required keys (name, principal, interestRate, tenure) and an optional overrides key, and calculation_method is the default strategy. This adds significant meaning beyond the minimal schema.

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?

Description clearly states 'Compare EMI outputs for multiple loan scenarios in a single API call,' using a specific verb and resource. It distinguishes itself from sibling tools like calculate_emi and calculate_schedule by emphasizing the multi-scenario comparison aspect.

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 (when comparing multiple scenarios in one call) but does not explicitly mention when not to use it or name alternatives. Sibling tools exist, but no direct comparison or exclusion is provided.

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