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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds real behavioral value beyond that: it discloses the two-phase response (in-progress build step vs ready preview) and enumerates the ready-state payload, which matters because there is no output schema.

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?

Two sentences, front-loaded with the action and identifier, followed by the return-shape list. The second sentence is a dense enumeration, but since no output schema exists that content earns its place; minor loss for the run-on list.

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 carries the return-value burden and does so thoroughly, covering both processing and ready states. It omits error handling for an invalid/expired handle and polling cadence, which are the remaining gaps for a 1-parameter retrieval tool.

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 100% for the single 'preview' parameter. The description's mention of 'handle or URL' corroborates the schema but adds no new syntax, format, or validation detail, so it sits at the baseline.

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 opens with a specific verb and resource ('Retrieves a front desk preview using its handle or URL'), so the agent knows exactly what it fetches and what input identifies it. It implicitly separates itself from build_front_desk_preview by requiring an existing handle/URL, but it never names a sibling explicitly, so it falls short of the 5 bar.

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 phrase 'Returns the current build step while processing' implies this is a polling/status-check tool, which is usable guidance, but the description never states when to pick this over build_front_desk_preview or ask_front_desk_preview. Usage is inferable rather than stated.

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