Capture view

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

Annotations already establish read-only, idempotent, non-destructive, local (openWorldHint=false) behavior, so that burden is lifted. The description adds real value beyond them: the PNG is returned both as an image and a path, savePath writes a file to the local PC, and the capture requires a live app — none of which the annotations convey.

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?

Front-loaded with purpose, then parameter semantics, then return behavior — a good funnel. The duplicated '[bulc-mcp] Returns the picture as an image' sentence repeats the first paragraph, and the trailing rules-reference line is boilerplate rather than descriptive content.

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?

No output schema exists, so the description correctly steps in to describe the return (image plus path, optional file copy). For a 5-param, zero-required capture tool the definition is nearly complete; only edge cases like maxWidth's default interplay and failure modes when no app is running are unstated.

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 coverage is only 60% (view and region carry enum values but no descriptions), so the description must compensate — and it does, explaining each view enum value's meaning and that region=viewport captures only the drawing area vs. window. It says nothing extra about maxWidth beyond the schema, and savePath's absolute-path requirement is already in the schema.

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 specific verb+resource: 'Screenshot of the running app for visual checking', then enumerates the five view modes (current/2d/3d/result/shape) so the agent knows exactly what each capture targets. This differentiates it from shape_screenshot (Shape Studio-specific) and result_* 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?

Gives clear context ('for visual checking') and a hard prerequisite ('Live app only'), plus the 'story = story id to show in 2D' routing rule. It does not, however, explicitly name an alternative for capturing Shape Studio (shape_screenshot) or state when this is the wrong choice.

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