wb_screenshot

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly mentions the reliability-motivated default format, auto-retry with smaller jpeg on timeout, path return, image embedding under a size cap, and error format including problem and hint. This is strong transparency for a screenshot tool, though it does not cover potential side effects or permission requirements.

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?

Four short sentences, each with a distinct purpose: purpose, format default/retries, return behavior, and error format. No filler or repetition. The most important information (what it does) is front-loaded in the first sentence.

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 5 optional parameters and no output schema, the description covers the key runtime behaviors: return value (path), embedding, retries, and error structure. However, it lacks any description of what the 'path' parameter does as an input, and does not mention potential side effects or restrictions. Overall, it is reasonably complete for a screenshot utility.

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 80% (format, quality, session, selector have descriptions), so the baseline is 3. The description adds context about format reliability and retries, but it does not explain the 'path' parameter, which remains ambiguous (input destination vs. output path). The description fails to fully compensate for the 20% gap in schema coverage.

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: 'Screenshot current tab (or selector).' It immediately distinguishes the tool's purpose from siblings like wb_get_text or wb_navigate, and the mention of selector adds a specific capability. The behavior described (format, retries, embedding) reinforces a unique identity.

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 no guidance on when to use this tool instead of siblings such as wb_snapshot or wb_get_text. It does not mention exclusions or alternative tools, leaving the agent to infer usage solely from the purpose statement. The 'use for large pages' hint appears only in the schema's selector parameter, not in the main description.

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