web_preview

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

With no annotations, the description carries the burden and does add real boundaries: it reads (returns) rather than mutates, it captures no screenshot, and it flags that pause/undo/restore/confirmed-export belong to the human dashboard, not this tool. It does not state permissions, idempotency, or freshness/caching behavior of the returned revision, keeping it below a 5.

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?

Three short sentences, front-loaded with the return value in the first sentence. Each sentence earns some place, though the third sentence is primarily a disambiguation against the screenshot sibling rather than essential here.

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 zero-param, no-output-schema tool, the description covers what is returned (a URL and a revision) and the notable scope boundary (no screenshot, dashboard-only controls). It does not explain what the returned URL is useful for or when the revision might change, which is a minor gap.

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?

The tool takes zero parameters, so the baseline is 4. There is nothing for the description to disambiguate, and it does not add misleading parameter-like guidance.

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: returns the loopback live-preview URL plus the current revision. It distinguishes itself from web_screenshot_note by explicitly saying no screenshot is captured, but it does not differentiate from the other web_* siblings (web_pages, web_timeline, web_checkpoint), so it falls short of a 5.

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?

Usage is only implied: an agent would infer this is called when it needs the preview URL or revision. The clause about the human dashboard controlling pause, undo, restore and confirmed export hints at what this tool does NOT do, but no explicit when-to-use or when-to-prefer-an-alternative statement is given.

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