Selenium MCP Server

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 action but omits critical details such as whether navigation is synchronous or asynchronous, error handling (e.g., invalid URLs), side effects (e.g., page reload), or performance implications. This leaves significant gaps in understanding how the tool behaves beyond the basic 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 extremely concise at three words, front-loading the core action without any wasted text. Every word ('Navigate to a URL') directly contributes to understanding the tool's purpose, making it efficient and easy to parse.

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 complexity of browser navigation (which can involve errors, delays, or state changes) and the lack of annotations and output schema, the description is insufficiently complete. It does not address what happens after navigation (e.g., success/failure indicators, page load events), leaving the agent without necessary context for effective use in a workflow.

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 input schema has 100% description coverage, with the 'url' parameter clearly documented as 'The URL to navigate to'. The description adds no additional meaning beyond what the schema provides, such as URL format requirements or examples. Since schema coverage is high, the baseline score of 3 is appropriate, as the schema adequately handles parameter semantics.

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 'Navigate to a URL' clearly states the action (navigate) and target resource (URL), making the purpose immediately understandable. However, it does not differentiate this tool from potential siblings like browser_click or browser_type, which also involve browser interactions but perform different actions.

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 lacks context such as prerequisites (e.g., browser must be open), exclusions (e.g., not for clicking or typing), or comparisons to sibling tools like browser_wait_for, leaving the agent to infer usage from the tool name alone.

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