Mcp Take Screenshot

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

With no annotations, the description carries the full burden, and it does disclose the genuinely useful fact that output lands in the shared artifacts volume rather than being returned inline. However, it says nothing about whether the tool navigates the page itself, whether it requires an already-loaded browser session, or what side effects the capture has.

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?

A single front-loaded sentence with the core action first and the optional modifiers parenthesized. No filler, no repetition of schema or title.

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?

An output schema exists, so return values need not be explained, and the destination volume is noted. For a three-parameter capture tool this is close to sufficient, with only selector semantics and session prerequisites left implicit.

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 map all three parameters conceptually: url, "element-scoped" (selector), and "full-page" (full_page). It stops short of clarifying selector syntax or how selector and full_page interact when both are set, so the compensation is only partial.

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?

"Screenshot a URL" gives a specific verb and resource, and the parenthetical scope modifiers clarify the operation. It is clearly distinguishable from mcp_browser_navigate and mcp_extract_table by the capture semantics, though it never explicitly contrasts itself with those 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?

There is no statement of when to use this versus mcp_browser_navigate (which presumably must run first to load a page) or mcp_extract_table. Usage is only implied by the verb; no prerequisites, exclusions, or alternatives are named.

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