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

The description goes beyond annotations by clarifying this is 'a referral, never a sale to a consumer' and by explaining where the intent goes under each decision. It does not cover authentication, audit trails, or envelope details, but the annotations already signal a state-changing operation.

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, front-loaded sentence carrying all routing information. It earns its content, but the parentheticals and dash make it harder to parse than necessary; splitting it into conditions would improve readability.

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?

The output schema exists, so return values need no description, and the allow/deny behavior is explained. But A2A jargon such as 'envelope + card URL', 'market agent of the ship-to', and 'regulator's home page' is left undefined, and optional-parameter behavior is not addressed.

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%, so the description must compensate. It connects 'decision' to decision_id, 'counterparty card URL' to counterparty_card_url, and 'order intent' to intent_id. However, it never specifies how allow vs deny is represented in decision_id, nor whether parameters may be null or which combinations are valid.

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 names a concrete action ('Hand the buyer') and resource ('the right agent'), and immediately narrows the mechanism to Agent-to-Agent. The allow/deny branch logic makes the tool's function distinct from transaction or gating siblings like gate_transaction.

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 states when to route to the counterparty's agent (allow decision) versus the market agent of the ship-to (deny decision). It provides clear context but does not name sibling alternatives or state explicit when-not-to-use conditions, so it falls short of a 5.

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