Exists

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. It only states the function without revealing behavior such as return values, error handling, permissions, or side effects. This is a significant gap for a simple tool that could behave in different ways.

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, clear sentence with no wasted words. It is appropriately brief for a simple tool, and the core action is front-loaded. Every word earns its place.

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?

The tool is simple but lacks context on return value and behavior. An output schema exists but is not described, and the description doesn't mention what the tool returns (presumably a boolean). Without annotations, this is insufficient for an agent to call it correctly and interpret the result.

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 schema has one required parameter 'path' with zero description coverage. The tool description does not explain what 'path' means, its format, or constraints (e.g., absolute or relative, file or directory). This leaves ambiguity about the expected input, and the description adds no clarity beyond the schema's type.

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 the specific verb 'check' and clearly identifies the resource as path existence. It is unambiguous and distinct from siblings like read_file or list_dir, which have different purposes. Even though it doesn't explicitly contrast with stat, the intent is clear and singular.

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 no guidance on when to use this tool versus alternatives such as stat or list_dir. It simply states the function without context on when it is the right choice, leaving the agent to infer based on the tool name alone.

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