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

Annotations already declare destructiveHint=true, idempotentHint=true, readOnlyHint=false and openWorldHint=false, so the safety profile is covered structurally. The description adds nothing beyond that — no statement that the watch is permanently removed, whether the secret must match the original, or what happens to a repeated cancel.

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 short sentence with no wasted words, but the brevity comes at the cost of under-specification rather than being lean-yet-complete.

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?

Output schema exists so return values need not be explained, but for a destructive mutation with a natural create/cancel sibling pair, the description omits the relationship to watch_domain and where the secret originates. An agent has the schema and annotations but not the operational context.

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 carries the full burden. It names both inputs ('id and secret') but adds no meaning: it doesn't say watch_id is the identifier returned by watch_domain, nor that secret is the credential issued at watch creation.

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 ('Cancel') and resource ('a watch') plus the identifiers needed, so an agent can tell it apart from the create-side sibling watch_domain. It never names the sibling or mentions domains, so differentiation is left implicit.

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?

No when-to-use, when-not-to-use, or alternative is given. An agent has to infer that this is the inverse of watch_domain and that it requires credentials issued at watch-creation time.

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