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

With destructiveHint=true already declared, the description still adds meaningful context: the trade only becomes final once both sides mark complete, the action cannot be undone, and user confirmation is required. That is real value beyond the annotation, though it does not cover error or validation 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?

Three tightly packed sentences with no filler: the trigger, the irreversibility warning and confirmation requirement, then the scope exclusion. The most decision-relevant information (when to use it) is front-loaded.

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?

Annotations carry the safety profile, an output schema exists so return values need no explanation, and the description covers trigger, irreversibility, confirmation, and a scope exclusion. Nothing an agent needs to invoke this correctly is missing.

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 a single parameter with 100% schema description coverage and a strict UUID pattern, so the schema fully documents it. The description adds no format, sourcing, or lookup guidance beyond what the schema already provides, which is the expected baseline.

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 specific verb and resource ('mark my side of a trade complete' / 'their side of an active Handshake is done') and scopes it to a post-exchange moment. It is clear on its own, but it never differentiates itself from similarly named siblings such as confirm_handshake or verify_handshake_payment, which an agent could plausibly confuse it with.

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 trigger condition is explicit: use it after the real-world exchange has happened and the user says their side is done, and confirm with the user first. It also carves out a when-not ('reviews are left on the website, not through this tool'), but it does not name alternative tools for adjacent actions, so there is no explicit routing guidance.

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