browser_take_screenshot

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

With no annotations, the description carries the full burden. It adds a genuinely useful behavioral fact — 'main' and 'support' browsers 'share nothing' — and implies a single one-shot capture, but says nothing about the return format (image, base64, file path) or any side effects.

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 short sentences, front-loaded with the core action and followed by the parameter note. Nothing is padded or redundant beyond the mildly decorative 'on demand'.

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 one-optional-parameter capture tool with no annotations and no output schema, the definition covers parameter semantics and browser isolation but omits what the tool actually returns and any precondition (an open/navigated page). Adequate but with a real 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 0%, so the description must compensate, and it does: it gives the default for 'browser' ('main unless you say support') and clarifies the isolation semantics between the two values. It covers the only parameter's meaning well.

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 states a specific verb and resource ('One screenshot of this browser's page'), which distinguishes it from siblings like browser_snapshot, browser_read_text, and browser_read_html. It stops short of explicitly naming the sibling it differs from, but the intent is 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?

'On demand' is the only usage cue and it is vague; it does not explain when to prefer this over browser_snapshot or browser_read_html, nor does it give prerequisites such as needing an open page. No when-not guidance is offered.

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