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

No annotations exist, so the description carries the full burden. It usefully discloses the 'watch entitlement required' prerequisite, but says nothing about whether watchers are persistent, idempotent, or what side effects/notifications a watch produces.

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 that is front-loaded with the action and scope. It is appropriately terse, though its terseness contributes to the missing mechanics noted elsewhere.

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 tool with no annotations, no output schema, and no parameters, the description is too thin: it does not explain how the endpoint is selected, what a watch object contains, or how it relates to the sibling snapshot and verdict tools. The entitlement note is helpful but insufficient.

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?

The tool has zero parameters, which is the baseline-4 case under the scoring rules. There is no parameter schema to elaborate on, and the description correctly does not invent parameters.

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 provides a specific verb ('Watch') and resource ('an endpoint') plus the purpose ('status/surface changes'), which differentiates it somewhat from the sibling list_watches (list vs add). However, it leaves the core mechanics vague: with zero parameters, it never explains which endpoint is watched or how it is identified, so the agent cannot fully tell what the tool operates on.

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 explicit when-to-use or when-not-to-use guidance is given, and no alternatives are named. It doesn't explain how this relates to list_watches, take_snapshot, or combined_verdict, leaving the agent to infer that this is the setup step.

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