webview_screenshot

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

The description discloses key behaviors beyond the readOnlyHint annotation: captures only visible viewport, targeting logic (only/appIdentifier), and the filePath behavior. The annotation already marks it as read-only, so the description adds value with technical constraints. No contradictions.

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 extremely concise: two sentences plus a brief note about alternatives. It front-loads the key constraint ('Tauri Apps Only') and uses clear, direct language. Every sentence adds essential information with no redundancy.

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?

Given 6 parameters, no output schema, and 19 sibling tools, the description is sufficiently complete. It covers prerequisites, limitations, targeting, and alternatives. The schema covers parameter details. Minor omission: no mention of return format (base64 vs file) beyond the filePath note, but the schema covers that implicitly.

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 coverage is 100%, so the input schema already documents all parameters. The description only adds context for `appIdentifier` (default behavior). Other parameters are not elaborated. Baseline 3 is appropriate since schema does the heavy lifting, with minor added value.

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 clearly states the tool's purpose: screenshotting a Tauri app's webview, specifying it requires an active driver session and captures only the visible viewport. It distinguishes itself from browser screenshot tools (Chrome DevTools MCP) and notes incompatibility with Electron apps, making the scope unambiguous.

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 provides explicit when-to-use and when-not-to-use guidance. It states the tool is for Tauri app webviews, requires a driver session, and gives an alternative for browser screenshots. It also warns that Electron apps will not work, which helps the agent avoid incorrect invocations.

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