Browserbase 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 communicates that this is a mutation tool (performs actions) and emphasizes atomicity, but lacks details on error handling, timing, or what happens if the element isn't found. The guidance about using variables for sensitive data adds some behavioral context.

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 with two sentences that each serve a clear purpose: the first defines the tool's function with examples, the second provides critical usage guidance. It's front-loaded with the core purpose, though some repetition with the schema reduces efficiency.

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?

For a mutation tool with no annotations and no output schema, the description does a good job covering the essential context: what the tool does, when to use it, and critical constraints. It could be more complete by addressing error scenarios or response format, but given the schema's thorough parameter documentation, it's reasonably comprehensive.

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 description coverage is 100%, so the schema already documents both parameters thoroughly. The description doesn't add any parameter information beyond what's in the schema - it essentially repeats the same guidance about atomic actions. This meets the baseline for high schema coverage.

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 'performs an action on a web page element' with specific examples like 'Click the sign in button' or 'Type 'hello' into the search input'. It distinguishes itself from siblings by focusing on atomic actions rather than navigation, observation, extraction, or session management.

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 explicit guidance on when to use this tool ('as atomic and specific as possible') and when not to use it ('AVOID actions that are more than one step'). It also references an alternative sibling tool ('If unsure, use observe before using act'), which helps the agent choose between act and observe appropriately.

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