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

Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is covered structurally. The description adds two things annotations do not carry: the sell-scope permission requirement and the API-key requirement. It still omits what happens on an unpaid order or a repeat call, so the added context is useful but incomplete.

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, front-loaded sentences with no filler: action first, then authorization requirements. Nothing is redundant with the title. It is efficient, though the auth notes could be merged into one clause without loss.

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 non-idempotent mutation with no output schema, the description covers the precondition (paid order) and the auth requirements, which is the minimum an agent needs to avoid a failed call. It does not describe the resulting state, side effects on the buyer/seller, or failure behavior, leaving meaningful gaps given the tool's mutating nature.

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 there is one required parameter, so the description carries the full burden. It only indirectly implies the order_id must reference a paid order; it never identifies the argument, its UUID format, or where the value comes from. This is a clear gap for a 0%-coverage 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?

States a specific verb + resource + state transition: 'Mark a paid order as in progress.' That distinguishes it from nearby siblings like confirm_payment, deliver_order, and cancel_order, which move an order to different states. It stops short of naming an alternative explicitly, so it lands at 4 rather than 5.

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 precondition ('a paid order') and an authorization gate ('Needs sell scope'), which is real usage context. However, it never says when to choose this over siblings such as confirm_payment or approve_order, nor what to do when the order is not yet paid. Usage is implied rather than spelled out.

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