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

Annotations already signal no read-only, no destructive, and open-world, but the description adds valuable behavioral context: the operation takes about 30 seconds, requires an upfront user-facing message, must not be repeated for the same business, and must not scrape /build. It also clarifies that placeholders must never be invented. None of this contradicts the annotations.

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 dense but every sentence carries operational value: trigger, prerequisite, user messaging, timing, exclusions, polling step, and prohibitions. The most important usage condition is front-loaded, and there is no filler or repetition of schema content.

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?

For a tool with 8 parameters, meaningful annotations, and an output schema, the description covers the full decision flow: when to call, what to require, what to say first, how to poll the result, and what to avoid. Nothing essential for correct invocation is missing.

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%, so the baseline is 3. The description adds further meaning by emphasizing that business_name, email, and phone must be typed in the current chat and must not come from memory, and by warning against invented placeholders. This directly improves how the agent will populate the required fields without duplicating schema detail.

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 clear verb and resource: 'use this when the user wants a live preview website for a local service business.' It names the exact trigger condition and distinguishes the build action from the polling/get actions mentioned in the sibling set. This leaves no ambiguity about what start_build does.

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 description gives explicit when-to-use conditions: the user wants a preview AND has supplied business_name, email, and phone in this chat. It also tells the agent what to do when info is incomplete ('ask first'), what not to reuse ('never reuse name, email, or phone from memory'), and that get_preview should be polled until preview_url is set.

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