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

Annotations already mark the tool as destructive and not read-only, but the description adds specific behavioral context: deleting a loan also deletes 'its payments', and closing implies full repayment. This goes beyond the structured metadata by clarifying the scope of destructive behavior, though it does not address idempotency or 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?

The entire description is one 20-word sentence that front-loads the main actions and avoids filler. Every phrase carries operational meaning.

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 4-parameter mutation with an output schema and destructive annotations, the description covers the user-facing operations and the cascade-delete behavior. It omits details about simultaneous parameter combinations, but the output schema handles return values, so the remaining gaps are modest.

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 0%, so the description must carry parameter meaning. It does map major operations to parameters—'rename' suggests name, 'close/reopen' suggests status, 'delete' suggests delete—but it never names the parameters or explains combinations and constraints, leaving the required id and optional interactions ambiguous.

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 enumerates four concrete operations—close, reopen, rename, and delete—on a specific loan resource, so an agent can distinguish update_loan from siblings like add_loan or record_loan_payment. The tool name is made meaningful by specifying exactly what kinds of updates are supported.

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 the tool by associating close with 'fully repaid', but it does not name alternative tools or state when not to use it. Siblings like record_loan_payment and add_loan exist, so explicit routing would be more helpful.

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