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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds useful detail beyond that: the result is a clickable TOS link plus instructions for account creation, which tells the agent what the payload contains and how it fits the onboarding flow.

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?

Purpose and usage are front-loaded in two tight sentences. The trailing example call block is mildly redundant for a zero-parameter tool but not harmful.

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?

An output schema exists, so return-value details need not be spelled out, and the description still summarizes the payload. For a trivial no-argument retrieval tool this is essentially complete, with only the unused example line as excess.

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, which is the baseline-4 case. The description correctly implies a no-argument call, and there is nothing further to document in the 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 opens with a specific verb+resource: 'Retrieve the FAA (Free App Analytics) Terms of Service document link.' It is unambiguous and easily distinguished from the sibling create_acc_and_get_auth_key tool, which performs a different action.

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?

'Use this tool when the user wants to review the Terms of Service before creating an FAA account' gives explicit triggering context and ties it to the account-creation prerequisite. It does not name the sibling tool as the alternative, but the sequencing is clear.

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