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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so safety is covered. The description adds real value beyond that: build duration expectations, a warning against rapid polling, and the meaning of the 'reply' field as the builder's summary.

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?

Front-loaded with the status enumeration, then usage timing, then Args. Every sentence earns its place, though the Args block is slightly verbose relative to the two simple parameters.

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 needn't be explained, yet the description helpfully names the 'reply' field. With parameters fully documented and usage context provided, nothing critical is missing for correct 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?

Schema coverage is 0%, so the description carries the full parameter burden and does so well: project_id is sourced from create_website or list_projects, and build_id is optional, sourced from create_website, and defaults to the latest build. It omits only the string format of the IDs.

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 ('Status of a website's AI build') and enumerates the possible return states (running, completed, failed, none). No sibling tool reports build status, so the agent can distinguish it immediately.

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?

Explicitly says to use it 'after create_website or edit_website' and adds timing guidance ('wait a little between checks rather than polling rapidly'). It gives clear when-to-use context but no explicit when-not or named alternative, since no sibling performs this role.

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