CloakMCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes what the tool does (takes annotated screenshots with numbered elements), mentions the output format (file path to saved PNG, element count), and explains the relationship with cloak_snapshot. However, it doesn't mention potential side effects like file system changes or performance implications.

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?

The description is perfectly structured and concise: purpose statement first, usage guidelines second, return values third, and parameters last. Every sentence earns its place with no wasted words, and information is front-loaded appropriately.

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 the tool's complexity (visual capture with annotations), no annotations, and the presence of an output schema (which covers return values), the description is mostly complete. It explains purpose, usage, parameters, and the relationship with sibling tools. The main gap is lack of behavioral details like file storage location or performance characteristics.

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?

With 0% schema description coverage and 2 parameters, the description compensates well by explaining both parameters: 'page_id: Target page ID' and 'full_page: Capture entire scrollable page (default: viewport only)'. It provides clear semantic meaning beyond what the bare schema offers, though it doesn't elaborate on format constraints for page_id.

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 clearly states the specific action ('Take an annotated screenshot with element indices overlaid') and distinguishes it from its sibling tool cloak_snapshot by specifying it's for VISUAL context like images, charts, CAPTCHAs, or layout. It provides a clear verb+resource combination that differentiates it from other tools in the list.

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?

The description explicitly states when to use this tool ('Use when you need VISUAL context — images, charts, CAPTCHAs, or layout') and when not to use it ('For most interactions, prefer cloak_snapshot() instead'), providing clear alternatives and context for tool selection.

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