Browser Instrumentation 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 effectively describes key behaviors: the session starts in 'observation-only mode' and 'actions require explicit escalation,' which are crucial for understanding permissions and safety. It also hints at the return format ('Confirmation message with session name and status'), though it could add more detail on error handling or session management.

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 well-structured and front-loaded, starting with the core purpose, followed by behavioral notes, and then parameter and return details in labeled sections. Every sentence adds value without redundancy, 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 session management, no annotations, and an output schema (implied by 'Returns' section), the description is mostly complete. It covers purpose, behavior, parameters, and returns, but could enhance completeness by mentioning prerequisites (e.g., needing an existing CDP session) or error cases, though the output schema may handle some of this.

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 schema description coverage is 0%, so the description must compensate. It provides clear semantics for both parameters: 'name' as a 'Unique name for the session' with examples, and 'cdp_url' as a 'CDP websocket URL' with examples. This adds essential meaning beyond the bare schema, fully documenting the parameters.

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 ('Connect to an existing browser session') and resource ('over CDP'), distinguishing it from sibling tools like browser_session_create (which creates new sessions) and browser_session_list (which lists sessions). It provides a precise technical context that differentiates its purpose.

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 implies usage context by stating 'Sessions start in observation-only mode. Actions require explicit escalation,' which suggests this tool is for connecting to existing sessions rather than creating new ones. However, it does not explicitly compare to alternatives like browser_session_create or specify when not to use it, leaving some guidance implicit.

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