Compose a page from blocks

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety profile is covered and the description does not contradict them. It adds genuine behavioral value by disclosing that output is a plan (ordered blocks, install commands, page.tsx scaffold, complete templates) rather than a mutation, though this overlaps the 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 verb and resource before the return description. Every clause carries weight and there is no filler, though the return summary is only moderately compact.

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 spelled out, and the purpose is well covered. However, with 0% schema description coverage, the two non-required parameters (includePro, packageManager) are left fully undocumented in both schema and description, leaving the definition incomplete 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 description coverage is 0%, so the description must carry the burden of explaining the three parameters. It illustrates what 'intent' looks like via examples, but includePro and packageManager are never mentioned, leaving two parameters entirely undefined.

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+resource ('Plan a page from Ballmac UI blocks') and illustrates with two concrete intent examples, making the tool's function unmistakable. It does not explicitly name or contrast with siblings like search_items or get_setup, so differentiation is implied rather than stated.

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 examples ('SaaS landing page with pricing and FAQ', 'login screen') imply when to reach for this tool, i.e., when the user describes a whole page rather than a single component. There is no explicit when-not guidance or named alternative for narrower lookups handled by sibling tools.

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