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

Annotations only declare readOnlyHint=true, and the description reinforces that plus discloses the full return surface (status, preview_unreachable_reason, last_error, created_at, expires_at, staging cluster, agent online state) that would otherwise be invisible with no output schema. It stops short of describing pagination, result limits, or ordering, which keeps it out of the top band.

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?

Purpose and scope are front-loaded before the long enumerations of returned fields, and the routing and prohibition come last, which is a sensible order. The single sentence is dense and somewhat list-heavy, but nearly every clause carries information an agent needs.

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?

With no output schema, the description correctly compensates by enumerating the returned fields, and with a one-parameter schema and readOnlyHint annotations the safety and input story are fully covered. An agent has everything needed to select and invoke this tool correctly.

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 only input parameter, application_id, is fully documented in the schema (100% coverage) with an adequate description, so the baseline is 3. The description's mention of workspace_id/namespace/preview_url refers to keys for inspect_demo, not this tool's own parameter, so it adds no meaning about application_id itself.

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 (list an Application's active demos, i.e. PR and branch previews) and enumerates exactly what a demo is, which immediately separates it from generic listing tools. It also names the sibling it hands off to (inspect_demo), so an agent can place it in the workflow without opening a schema.

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?

Gives an explicit trigger ('when the user names an application but not which demo or preview they mean, or asks whether a demo exists or is still running'), names the follow-up tool and the routing keys to pass to it, and adds a hard negative constraint ('Never search namespaces across clusters to find a demo'). Both when-to-use and when-not-to-use are covered.

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