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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered structurally. The description adds only the notion that this is a compact/fast first pass with optional heavy payloads (pixels/browser/OCR); it does not disclose cost, latency, size limits, or that OCR requires tesseract on PATH – that detail lives in the schema, not the description.

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, both front-loaded: the first states purpose and contents, the second states the preference rule and the narrowing alternatives. No filler, no restatement of the title, and the highest-value routing information comes last in the natural reading order.

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 an output schema present, return values need not be explained, and the description covers purpose, contents, and alternative routing for a 23-parameter tool. It is slightly thin on which optional payloads to enable for which situation, but the 100%-covered schema compensates for that 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?

Schema description coverage is 100% across 23 parameters, so the schema does the heavy lifting and baseline 3 applies. The description's category list (pixels, browser, OCR, semantic UI, clipboard) loosely maps to parameter groups but adds no syntax, precedence, or cost guidance beyond what the individual parameter descriptions already give.

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 (a first compact snapshot of desktop state) and enumerates exactly what it captures: windows, semantic UI, displays, clipboard metadata and optional pixels/browser/OCR. It also distinguishes itself from the crowded computer_*/ui_*/browser_* sibling set by naming the tools used to narrow afterwards (ui_find, browser_find, screenshot_region).

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?

Explicit when-to-use ("first compact view of an unfamiliar desktop state") plus an explicit preference rule ("Prefer it over repeated screenshots") that routes the agent away from take_screenshot loops. It then names three concrete alternatives for follow-up narrowing, so the fallback path is unambiguous.

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