agent-browser-mcp

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

No annotations are provided, so the description carries full burden. It mentions the action ('Set the active browser tab') but lacks details on behavior: e.g., what happens if multiple tabs match the URL substring, whether it fails if no match is found, if it requires specific browser state, or what the output includes. This is a mutation tool with zero annotation coverage, leaving significant gaps.

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, efficient sentence that front-loads the core purpose ('Set the active browser tab') and specifies the input criteria. There is no wasted verbiage, making it highly concise and well-structured for quick understanding.

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 2 parameters with 0% schema coverage, no annotations, and an output schema (which handles return values), the description is moderately complete. It covers the basic purpose but lacks behavioral details (e.g., error handling, matching logic) and parameter semantics, leaving room for improvement despite the output schema mitigating some gaps.

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 0%, so the description must compensate. It mentions parameters ('session id or URL substring') but doesn't explain their semantics: e.g., what a session_id is, how URL substring matching works (case-sensitive, partial match), or that at least one parameter should be provided. With 2 parameters and no schema descriptions, this adds minimal value beyond naming them.

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 action ('Set the active browser tab') and the target resource ('browser tab'), with specific criteria ('by session id or URL substring'). It distinguishes from siblings like 'list_tabs' (which lists tabs) and 'open_new_tab' (which creates new tabs), but doesn't explicitly contrast with 'open_url' (which might also activate tabs).

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 when needing to switch tabs based on session_id or url_pattern, but doesn't specify when to choose this over alternatives like 'open_url' (which might open and activate a URL) or 'list_tabs' (for tab discovery). No explicit when-not-to-use or prerequisite guidance is provided.

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