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

Annotations already mark the tool as read-only and open-world, and the description adds valuable behavioral context beyond that: results may change over time, may include third-party offers when enabled, and the user is directed to the bank's platform to apply. This gives a fuller picture of what the tool does and what the user should expect.

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 three sentences with no filler. The first sentence states purpose, the second explains the result payload and dynamic nature, and the third describes the user handoff. Every sentence earns its place.

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 a single optional parameter and an output schema present, the description covers the tool's scope, return values, dynamic behavior, third-party integrations, and the application flow. The only gap is the misleading APY mention, which prevents a perfect completeness score.

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 covers the only parameter, initialDeposit, with a clear USD description. However, the description also mentions 'desired APY' as a matching criterion even though no APY parameter exists in the schema. This can mislead the agent into expecting a second input that isn't available, creating confusion rather than adding value.

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 opens with a specific action ('Search SecureLend's lender database') and clearly identifies the resource ('savings accounts') with matching criteria and return payload. This makes the tool's purpose obvious and distinguishes it from sibling comparison tools targeting other account types.

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 clearly states the exact use case: comparing savings accounts based on initial deposit and desired APY. Although it doesn't name alternative tools or exclusions, the context is specific enough for an agent to know when to select this tool among the many compare_* siblings.

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