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

Annotations already mark this as destructive and non-read-only, so the description's real value is the financial settlement rule: consumed units are final and unused USDC is refunded. That is meaningful mutation context beyond the annotations, though permissions, irreversibility, and stream-state side effects remain undisclosed.

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?

Two tight sentences, front-loaded with the action and followed by the settlement outcome. The only inefficiency is the unexplained 'Class C' jargon, but no sentence is wasted.

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 destructive mutation with no output schema and two entirely undocumented required parameters, the description covers the refund outcome but leaves critical gaps: parameter meaning, authorization requirements, and what happens to the stream state after cancellation.

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% for both required parameters, and the description never explains intentId or agentId. With low coverage the description was expected to compensate, and it does not.

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 and resource: cancels a streaming intent, with the actor scope 'either party.' It is distinguishable from cancel_deal by the 'streaming intent' object, though the unexplained 'Class C' label adds jargon rather than clarity.

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?

Says either party may cancel but gives no when-to-use criteria, prerequisites (e.g., active stream state), or alternatives such as cancel_deal or open_dispute. The agent must infer when cancellation is appropriate.

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