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

Annotations already declare readOnly=false, destructive=false, idempotent=false, so the write-safety profile is covered. The description usefully adds that the intent 'settles by x402', disclosing a financial settlement side effect not visible in the annotations, but it does not clarify reversibility, auth requirements, or failure behavior.

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?

A single dense sentence that front-loads the core action ('Open an order between two agents'), though the trailing clause about x402 settlement and the stray field names make it read as slightly run-on.

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 described, but for a five-parameter creation tool with 0% schema coverage the description leaves the required inputs (gtin, quantity, decision_id) entirely unexplained and cites fields that are not parameters.

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 none of the five parameters (gtin, market, ship_to, quantity, decision_id) are explained in the description. Worse, it references 'reason_code + rule_set_version', which do not map to any actual parameter, so it adds no usable meaning for the real inputs.

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 clear verb+resource ('Open an order between two agents') and differentiates itself from siblings by tying the intent to 'a cleared item after the gate', which positions it downstream of gate_transaction. It is somewhat jargon-laden ('order intent', 'a2a-x402.ai') but an agent can tell it creates a new order rather than reading or verifying one.

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?

Usage is only implied: the phrase 'after the gate' signals a precondition relative to gate_transaction, and 'for a cleared item' implies the item must already be cleared. No alternatives are named and no explicit when-not-to-use is given.

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