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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral context beyond annotations: it says the recomputation is free forever (GR5), compares against certified numbers, and returns a purchase_id for an independent external check.

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 description is a single dense sentence that covers the main action and output. It is appropriately sized, though the leading 'FREE forever (GR5)' cost marker is not the most important information for tool selection.

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 values need not be explained in detail, and annotations cover the read-only/idempotent behavior. The description adds cost, recomputation logic, and external-check context, but leaves a small gap around what a certificate_id is and where to obtain it.

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?

There is one required parameter, certificate_id, but schema description coverage is 0% and the description does not explain its format, source, or expected value. It refers to 'a certificate's stored workload' but adds no concrete meaning beyond the parameter name already 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 uses specific verbs and resource: recompute a certificate's footprint, compare against certified numbers, and surface a clearinghouse purchase_id. This clearly identifies verification of an existing green certificate, but it does not explicitly differentiate itself from siblings like certify or list_green_certificates.

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?

The description implies the usage context: it surfaces the purchase_id needed for the independent x402-C verify_retirement check. However, it does not state when to use this tool versus alternatives such as certify or list_green_certificates, nor does it mention exclusions or prerequisites.

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