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

No annotations exist, so the description carries the full burden. It does disclose the return shape (both EMIs, net saving, break-even months) and that the fee defaults to zero, but it says nothing about the underlying assumption set — whether tenure is held constant, whether the fee is financed or paid upfront, or that the tool is a pure calculation with no side effects.

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 sentences, zero waste: the first front-loads inputs and outputs, the second supplies a compact example that resolves unit and formatting ambiguity. Nothing is repeated or padded.

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 output schema and no annotations, the description steps up by enumerating the three returned values, which is exactly what an agent needs to decide whether to call it. The remaining gap is methodological — the assumptions behind the saving and break-even figures — which matters for a financial comparison but is not stated.

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 100%, including units (rupees, annual percent) and bounds, so the schema already does the heavy lifting and baseline 3 applies. The description adds only marginal meaning beyond it — a default of 0 for processingFee and a concrete worked example that clarifies expected magnitude and format.

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 a specific verb-plus-resource framing: it names the exact inputs consumed (outstanding balance, months left, current/new rates, fee) and the exact outputs produced (both EMIs, net saving, break-even months). This makes it unmistakably a balance-transfer comparison calculator rather than a plain EMI tool, though it never names a sibling to route against.

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?

Usage is only implied by the tool's domain: an agent can infer it applies when a borrower is considering refinancing an existing loan. There is no explicit statement of when to prefer it over emi or sensitivity, and no prerequisites (e.g., that a processing fee of 0 is assumed when omitted) are called out.

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