close_all_instances

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 clearly states this is a destructive operation ('delete all related data') and specifies the permission requirement ('only admin can use this tool'). However, it doesn't describe what happens to active sessions, whether the operation is reversible, or what the output contains.

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 contains all essential information: the action, the scope, and the permission requirement. Every word earns its place with zero wasted text.

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 destructive admin-only tool with no parameters and an output schema, the description covers the critical aspects: what it does, its destructive nature, and permission requirements. The existence of an output schema means return values don't need explanation. However, it could benefit from mentioning irreversible consequences or confirmation requirements.

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?

With 0 parameters and 100% schema description coverage, the baseline would be 4. The description appropriately doesn't discuss parameters since none exist, which is correct for this tool's design.

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 specific action ('Close all browser instances and delete all related data'), distinguishing it from the sibling 'close_instance' tool which likely closes a single instance. The verb+resource+scope combination is precise and unambiguous.

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 context about when to use this tool ('only admin can use this tool'), which helps differentiate it from other browser management tools. However, it doesn't explicitly state when NOT to use it or name specific alternatives for partial cleanup scenarios.

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