start_browser

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

No annotations are provided, so the description carries the full burden. It only states 'start a browser session' without disclosing what happens if a browser session already exists, potential side effects, or resource implications. This lack of behavioral detail is a significant gap.

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?

Two sentences, no wasted words. The first sentence states the purpose, the second explains the usage scenarios. Perfectly 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?

For a simple tool with three optional parameters and no output schema, the description is fairly complete. It covers the main use cases. However, it omits edge cases like behavior when a browser is already open, which would be helpful for completeness.

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 only 33% (only window_size has a description). The description adds meaning for all three parameters: browser choices, headless mode, and custom window size, compensating for the low schema coverage. However, it does not describe the enum values or format details beyond what the schema provides.

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 starts a browser session and explicitly distinguishes it from the auto-start behavior of other tools. It specifies that this tool is for choosing Firefox, headless mode, or custom window size, making its purpose distinct from siblings.

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 clear context on when to use the tool (to select Firefox, headless mode, or custom window size) and implicitly indicates when not to use it (if default Chrome auto-start is acceptable). However, it does not explicitly name alternatives or exclusions beyond the auto-start behavior.

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