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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the tool does not perform the check itself but hands back a link plus steps, and it clarifies the target subjects. It stops short of saying what the link leads to or whether credits are involved.

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 tight sentences, front-loaded with what is returned and then the selection condition. Every clause carries information; nothing is filler.

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 parameterless tool with annotations covering safety and idempotency, the description covers purpose, routing and return shape adequately. Minor residual gaps remain about the link's destination and its relationship to credit-consuming siblings such as buy_credits.

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 takes zero parameters, so the schema baseline is 4. The description's enumeration of who the report can be requested for (tenant, applicant, borrower, yourself) adds framing that the empty schema cannot convey.

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?

States a specific verb (returns the link and steps to request) and a specific resource (a bank-based income report from Income Checker), and enumerates the subjects it applies to (tenant, applicant, borrower, yourself). It also distinguishes itself from the look-alike sibling how_to_verify_income by explicitly scoping to actually verifying rather than learning how.

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 second sentence gives an explicit use condition and a contrast: use it when the user wants to actually verify/check income, not just learn how. That effectively routes the agent away from how_to_verify_income, though it doesn't name that tool or address other siblings like send_verification_request or list_verifications.

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