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

Annotations already declare readOnlyHint=false, idempotentHint=false, and destructiveHint=false, so the description does not need to restate safety basics. It adds meaningful behavioral context by warning that the baseline cannot be edited afterward and only deleted, plus the need to confirm first.

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 purpose is front-loaded and the description is short enough to scan. It repeats the 'before the new terms start' timing idea, which slightly reduces conciseness but also reinforces an important constraint.

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 that annotations cover mutation/idempotency hints and an output schema exists, the description provides enough context for correct invocation: purpose, timing, immutability, and confirmation. It omits optional parameter semantics and permission details, but those are secondary here.

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 description explains the roles of covers, base_start, base_end, and changed_on in prose, tying them to the baseline period and first day of new terms. It does not explain the optional name or agreement_id fields, so with low schema description coverage it only partially compensates.

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 uses a specific verb, 'Freezes,' and identifies the resource as a savings baseline, with scope tied to covers, base_start/base_end, and changed_on. It is clear on its own, but it does not explicitly distinguish itself from savings-related siblings such as get_savings or forecast_spend.

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?

It gives a timing prerequisite: 'Do it before the new terms start,' and adds 'Confirm first.' However, it does not state when not to use this tool or name alternative tools/options, so usage guidance is implied rather than explicit.

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