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

The description adds operational context beyond the annotations: a human must verify the email and complete any payment. Since annotations already declare destructiveHint=true and readOnly=false, the description doesn't need to repeat those; it usefully warns about the manual step.

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 front-load the purpose and include the critical caveat. Every sentence earns its place with no repetition or fluff.

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?

It is adequate for tool selection: domain, alternative, and human step are clear. It is less complete for invocation because it leaves parameter semantics unterunched in spite of 7 parameters and 0% schema coverage, though parameter names and enums give some hints.

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%, and the description doesn't explain the required parameters planId, market, currency, or idemPotencyKey. It mentions email and payment loosely, but provides almost no guidance on how to populate the schema fields.

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 states a clear purpose: compatibility checkout for paid plans and Enterprise proposals. It also names the sibling alternative (dp_commercial_start_live_trial) for evaluation, which distinguishes it from other start_* tools.

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 explicitly says to use dp_commercial_start_live_trial for evaluation, giving an alternative for a different scenario. It also sets expectations that a human must verify email and handle payment, clarifying when this tool is appropriate.

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