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

With no annotations, the description carries full burden for behavioral disclosure. It reveals that the operation is read-only by the verb 'List' and that authentication via x-api-key is required, which is useful beyond the schema. It does not address response format, filtering semantics, or rate limits, so behavioral transparency is adequate but shallow.

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 front-loaded sentence: the primary action and object appear first, followed by the auth requirement. No filler or redundant restatement of the tool name.

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 parameterless, no-output-schema listing tool, the description covers the core information: what is returned and the required credential. It could add a sentence about the response shape or per-server scope details, but this is an optional enhancement rather than a gap for basic invocation.

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 input schema has zero parameters and 100% description coverage, so the baseline is high. The only credential mentioned, x-api-key, is outside the parameter list and is appropriately surfaced in the description. There are no parameter semantics to clarify.

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 an explicit action ('List') and resource ('active per-server watches') with a scope qualifier ('for this API key'). The verb differentiates it from sibling tools like census_watch_subscribe and census_watch_unsubscribe, so an agent can select it unambiguously.

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 gives clear context for when to call it: whenever the agent needs the current active per-server watches associated with the API key. It also states the required credential ('Requires x-api-key'), which is essential usage guidance. It does not explicitly discuss alternatives or exclusions, but the list/subscribe/unsubscribe sibling split is inferable from the verb.

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