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

Annotations already declare readOnlyHint, idempotentHint, and a closed world, so the safety profile is covered. The description earns credit for disclosing the deprecation/backwards-compatibility status and the fact that fees now apply immediately, but it says nothing about the response payload or whether the endpoint is slated for removal.

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 short sentences with no filler, and the deprecation status is front-loaded in the first clause. It is efficiently sized, though the second sentence compresses two distinct claims (waiver discontinued, fees immediate) into one.

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 no-parameter informational endpoint with no output schema, the description should say what the caller gets back and whether it is safe to skip. It covers the business state but omits the return content and any deprecation timeline, leaving a meaningful gap.

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 baseline is 4; there is no parameter meaning for the description to add or omit. Nothing in the description conflicts with the empty schema.

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 identifies the resource as the discontinued founding-trial terms and frames it as a 'historical compatibility endpoint,' which tells the agent it is about legacy trial terms. However, it never states what the tool actually returns (terms text? fee table? deprecation notice), so the purpose is only partially pinned down.

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?

No explicit when-to-use guidance and no alternatives named, despite obvious siblings (fee_schedule for current fees, kai_overview). The phrase 'standard graduated KAI fees apply immediately' implies the trial path is dead, but the agent is left to infer that it should consult fee_schedule instead.

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