close_browser

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

With no annotations, the description carries the behavioral burden, and it does state the key behavior: closing the active session and freeing resources. It implies irreversibility and that the session will no longer be usable, which is sufficient for this zero-parameter tool.

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?

A single, front-loaded sentence that states both the action and its purpose with no filler. Every word contributes to understanding the tool's function.

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 zero-parameter tool with no output schema, the description fully captures the necessary call context: what is closed, when it applies, and what the side effect of resource release is. Nothing essential is missing.

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 tool takes no parameters, so there is no parameter semantics burden. The baseline of 4 applies because the description cannot and does not need to add parameter meaning beyond the empty schema.

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 uses a specific verb ('Close') with a clear resource ('the active Selenium browser session') and an outcome ('free resources'). It distinguishes itself from sibling tools like manage_tabs by referring to the entire browser session rather than individual 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 clearly indicates this is the teardown/cleanup tool for a Selenium session, giving the agent a clear context for when to call it. It does not explicitly mention alternatives or exclusions, such as closing a single tab via manage_tabs, but the context is unambiguous enough for a simple lifecycle tool.

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