Execute a browser action

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

The description expands on annotations (destructiveHint=true) by explaining the destructive override prompt. It also adds that every call is recorded to an audit log, which is not in annotations. No contradiction with annotations.

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 a single paragraph that efficiently covers the core purpose, permission model, and audit logging. It is front-loaded with action types. Some minor restructuring could improve readability, but it remains concise.

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 (multiple action types, permission levels), the description covers the necessary behavioral context. It does not detail each action type, but the schema handles that. Output schema is absent but not critical. The coverage is adequate.

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 coverage is 100%, but the description adds context beyond schema: sessionId comes from list_recent_sessions, confirmToken is from request_authorization. This enhances parameter understanding slightly above baseline.

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: 'Execute an action (click/type/navigate/...)' in the user's live browser. It uses a specific verb+resource and lists examples, distinguishing it from sibling read-only or analysis tools like get_dom_snapshot.

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 usage guidance: it details permission levels (3+, 4), behavior of confirmToken banner vs auto-allow, and the destructive-action override always prompting. This helps the agent decide when and how to use the tool, including prerequisites.

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