playwright__browser_take_screenshot

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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=true). Beyond that, the description discloses a genuinely non-obvious behavioral trait: the returned image is static and cannot drive further actions, which steers the agent's downstream planning. It doesn't mention where output lands or size implications, but that is largely covered elsewhere.

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, purpose first and the routing caveat second; every clause carries information and nothing is padded or repeated from the schema.

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 usefully signals that the return is a non-actionable image and points to the alternative tool. Filename defaults and format inference are left to the schema, so almost nothing an agent needs is missing, though the destination/output-directory behavior is never surfaced in prose.

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%, with type/scale/target/element/filename/fullPage all documented in-schema including enum semantics and the fullPage/element conflict. The description adds no parameter-level detail, so the baseline 3 is appropriate.

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 concrete verb+resource ('Take a screenshot of the current page') and explicitly distinguishes itself from the sibling browser_snapshot, which is the main tool it could be confused with. An agent can separate the two without opening either schema.

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?

Gives a clear negative condition ('You can't perform actions based on the screenshot') and names the correct alternative (browser_snapshot) for action-based work. It does not state when a screenshot IS the right choice (e.g. visual verification, user-facing evidence), so guidance is strong but not fully bidirectional.

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