browser_take_screenshot

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

It discloses that screenshot output is not a substitute for element discovery and that capture can target a tab. However, with no annotations, the description leaves implicit what the tool returns, whether the fullPage option is honored by default, and any effects on browsing state. This is adequate for a simple capture action but not fully transparent.

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 contain the essential purpose, the sibling routing instruction, and the tab-targeting capability. It is front-loaded and contains no redundant wording.

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 a straightforward screenshot operation and fully documented parameters, the description is nearly complete. The only meaningful gap is the return format or behavior, but this does not prevent a correct call. The sibling routing and tab targeting are covered explicitly.

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%, so the schema already documents tabId, agentId, and fullPage. The description only reiterates tabId targeting and does not add new parameter semantics beyond what the schema provides. 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?

The first sentence names a specific verb and resource ('Take a screenshot of a page'), and the distinction from browser_snapshot is explicit: snapshots are for finding interactable elements. This makes it immediately identifiable among many browser siblings.

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?

It gives a clear exclusion — use browser_snapshot instead when the task is finding interactable elements — while leaving screenshots for visual capture. It also mentions the tabId option for targeting a specific tab, which orients the agent in multi-tab workflows.

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