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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description adds useful behavioral context: the returned values (id, level payment, effective annual rate) and the minor-unit conventions. It does not describe side effects beyond creation or address what happens when the free quota is exceeded, but it adds value beyond the annotations without contradicting them.

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 with no filler. The first sentence front-loads the action and return values; the second clarifies unit formats and a quota constraint. 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?

Given 14 parameters, high schema coverage, and no output schema, the description covers the key missing pieces: what the tool returns and the integer minor-unit semantics for monetary fields. It could further explain rate calculation or error conditions, but the essentials for invoking the tool correctly are present.

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 93%, so the schema already documents nearly all parameters. The description reiterates that principal_minor, fees, and balloon are whole minor units and that rate_bps is nominal in basis points, which is helpful reinforcement but adds little beyond the existing parameter descriptions.

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 a specific action ('Record a loan or lease') and specifies what it returns ('id, level payment and effective annual rate'), making the core purpose clear. It does not explicitly differentiate from sibling tools like loan_delete or loan_schedule, though the create/record semantics are unambiguous.

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 usage by virtue of being the creation tool among siblings, but it gives no explicit guidance on when to choose loan_create over related tools such as loan_journal or loan_schedule. No alternatives or exclusions are mentioned. The 'Free: 3 agreements' hint provides some quota context but not usage direction.

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