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

The description adds significant behavioral context beyond annotations: the operation is async ('poll with check_job'), deploys to managed hosting with HTTPS, returns a public URL in ~1-2 minutes, and lists the app. This complements the annotations (readOnlyHint=false, destructiveHint=false) without contradiction, though it does not detail auth requirements or rate limits.

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 compact (four sentences) and front-loaded with the core action and result. It includes the example and polling instruction without redundancy, making every sentence earn its place.

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?

Given the output schema exists, the description does not need to explain return values. It covers the full workflow: create, deploy, get URL, poll with check_job, and best-use guidance. The example ties it together. This is complete for a tool with this complexity and sibling context.

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 100%, so the baseline is 3. The description adds value through the example ('a tip calculator web app') and the phrase 'plain-language description,' which clarifies the primary parameter. It also implicitly explains 'refine' by noting it modifies an existing app, though that detail is in the schema. Overall, it slightly enhances parameter understanding beyond the schema.

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 clearly states the core action: 'Turn one plain-language description into a LIVE single-page web tool' with specific details about deployment and URL return. It distinguishes itself from siblings like check_job (polling) and get_app/list_apps (retrieval) by focusing on creation, and the example reinforces the purpose.

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 suggests the best use case: 'Best for tool-style apps: calculators, converters, checklists, timers, generators, small games.' It also provides the async workflow with check_job and a concrete example. However, it does not explicitly state when not to use it or mention alternatives like get_app/refine, so it is clear but not exhaustive.

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