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

Annotations already declare readOnlyHint and destructiveHint=false, so safety is covered; the description adds a genuinely non-obvious warning that captured page content is untrusted, which matters for how the agent treats returned text. It does not say what happens when no preview exists yet or what status values are possible, which keeps 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?

Two sentences, no filler, with the core read operation stated first and the trust caveat immediately after. Nothing could be removed without losing meaning.

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?

With no output schema, the description should characterize the return shape; "status and screenshot" is only a rough sketch of the two-part response. Combined with fully undocumented parameters, the definition is adequate but leaves real gaps for a tool that is likely polled repeatedly.

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?

Both required parameters (sessionId, previewId) have 0% schema description coverage and the description says nothing about them beyond the hint that the preview is "editor-owned", which weakly implies session scoping. An agent gets no explanation of which session/preview identifiers are valid or how to obtain them.

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?

"Read the current editor-owned preview status and screenshot" gives a concrete verb and two concrete resources, so the agent knows it returns a status plus image data rather than mutating anything. It stops short of distinguishing itself from neighbours like load_editor_preview or view_check_screenshot, which an agent could easily confuse for this read.

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?

There is no guidance on when to call this versus load_editor_preview (which presumably produces the preview) or view_check_screenshot (which also returns a screenshot). The word "current" implies it is a polling/refresh call, but that is inference rather than stated usage.

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