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

With no annotations, the description carries the full burden and does so excellently. It discloses what happens: the held authorization is discarded and buyer's funds remain untouched, and it highlights the condition that the operation is invalid after delivery verification. It also states the authentication requirement (either party's token), providing valuable context beyond simple cancellation.

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 three sentences, each earning its place: the first defines the action, the second explains the effect, and the third gives the key constraint and requirement. It is front-loaded and concise, with no superfluous words.

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 cancel operation with no output schema and no annotations, the description provides a complete picture: what it does, when it can be used, who can use it, what happens to funds, and the critical constraint. The agent has enough context to invoke the tool correctly.

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 coverage is 100%, so the parameter descriptions already define token, reason, and escrow_id. The description adds minimal new semantic value, mostly reaffirming that either party's token works, which the schema already states. Baseline 3 applies because the schema does the heavy lifting.

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?

Clearly states the tool's action: canceling an escrow before payment. The scope is explicit ('before payment') and it differentiates from sibling escrow tools by specifying the timing and that either party can initiate. This is a specific verb+resource+scope.

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 explicitly states when to use the tool ('before payment') and when not to ('Cannot be used after a delivery has been verified'), providing clear exclusions. However, it does not explicitly name alternative tools for post-delivery cancellation, so it misses the full 'alternatives' component for a 5.

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