set_work_package_watcher

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

Annotations already declare destructive=true, idempotent=true, openWorld=true, and readOnly=false. The description adds useful behavior beyond those annotations by documenting the asymmetric preview results and that the add-preview does not check whether the user already watches.

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 short and front-loaded, with the core operation stated first and the preview asymmetry explained in the following sentences. Every sentence carries relevant behavioral information.

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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. The description is nearly complete for invocation, but it omits the meaning of `user_id` and does not repeat the confirmation/approval requirement that appears in the schema.

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 50%; `confirm` and `work_package_id` are described in the schema, while `watching` gets clear semantic detail from the description. The required `user_id` parameter remains undocumented in both the schema and the description, so the description only partially compensates for the coverage gap.

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: add/remove a watcher on a work package. It is clearly distinguishable from the list_work_package_watchers sibling, though it does not explicitly name that or any other sibling as an alternative.

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?

It explains how the `watching` flag works (true adds, false removes) and warns about asymmetric preview behavior. However, it gives no explicit guidance on when to use this tool versus viewing watchers or other alternatives, so usage is only implied.

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