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

Annotations already flag destructiveHint=true and idempotentHint=true, so the bar is lower, and the description still contributes real information: historical bills are preserved, i.e. the blast radius is limited to the schedule. The trailing 'Free' is unexplained and adds noise rather than clarity.

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?

Three short sentences with the essential fact (permanence) and the key reassurance (past bills survive) front-loaded. 'Free' is the one sentence that doesn't clearly earn its place, since its meaning is ambiguous.

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?

A single-parameter destructive tool whose safety profile is fully carried by annotations, with the retention behavior spelled out. The only real gaps are the unexplained 'Free' and no mention of behavior when the bill is already stopped, which the idempotent hint partly covers.

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?

One parameter at 100% schema coverage, and the schema description already tells the agent to source the ID from purchasing_list_repeating_bills. The prose adds nothing about repeating_id, so the baseline 3 applies.

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?

A specific verb and resource ('Stop a repeating bill') with the added clarification that it is permanent ('for good'), which distinguishes it from a pause. The sibling set makes the save/list/delete split obvious, so no sibling need be named, but the description itself doesn't point at them.

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: 'Stop a repeating bill for good' tells the agent this is the terminal option, and 'the bills it recorded stay as they are' hints that voiding or deleting bills is a different operation. No explicit when-to-use or when-not-to-use guidance and no named alternative.

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