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 states the tool opens a new page/tab and optionally navigates, but doesn't describe what happens after creation (e.g., whether it becomes the active page, if it's isolated, or if there are limits on concurrent pages). For a tool that likely interacts with browser state, this is a significant gap in transparency, though it at least indicates the core action.

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 appropriately sized and front-loaded: the first sentence states the core purpose, and the second clarifies the optional parameter. The 'Args:' section is structured but minimal, avoiding redundancy. Every sentence earns its place with no wasted words, making it highly concise and well-organized.

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 low complexity (1 optional parameter) and the presence of an output schema (which likely covers return values), the description is somewhat complete but has gaps. It explains the basic action and parameter, but lacks behavioral details (e.g., page management) and usage guidelines relative to siblings. For a simple tool, this is adequate but not fully comprehensive, aligning with a minimum viable score.

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?

The description adds meaningful context for the single parameter 'url': it explains that it's optional ('Optionally navigate to a URL') and specifies its purpose ('URL to navigate to after creating the page'). Since schema description coverage is 0% (the schema only lists 'url' with a title 'Url'), this compensates well by clarifying semantics beyond the bare schema, though it doesn't detail format constraints like valid URL patterns.

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 tool's purpose: 'Open a new browser page/tab. Optionally navigate to a URL.' This specifies the verb ('Open') and resource ('new browser page/tab'), with an optional navigation action. However, it doesn't explicitly differentiate from siblings like 'cloak_navigate' (which might navigate an existing page) or 'cloak_launch' (which might launch a browser instance), so it doesn't reach the highest clarity level.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose 'cloak_new_page' over 'cloak_navigate' (for existing pages) or 'cloak_launch' (for starting a browser), nor does it specify prerequisites or exclusions. The only implied usage is for creating new pages, but this is basic and lacks explicit context.

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