file_exists

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 only restates the existence check without revealing return type (e.g., boolean), handling of directories vs. files, permission errors, or symlink behavior. This is a minimal description with no added behavioral context.

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 succinct sentence that directly states the tool's purpose. There is no redundant wording or filler, making it appropriately concise and front-loaded.

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 predicate tool with one parameter and an output schema, the description is minimally sufficient. However, it lacks any guidance on edge cases (e.g., directories, permissions) or usage context. Given the low complexity, completeness is adequate but not rich, hence a 3.

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 covers 100% of the parameter (path) with a clear description ('The path to check.'). The tool description adds the workspace scoping context but does not add syntax or format details. Since schema coverage is high, baseline 3 is appropriate.

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 'Check whether a path exists within the workspace' uses a specific verb and resource, clearly distinguishing it from sibling tools like file_info (which retrieves metadata) and list_directory (which lists contents). It states the exact condition being tested and the scope (workspace).

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. It does not mention typical use cases such as verifying a path before reading/writing, nor does it contrast with related tools like file_info or read_file. This leaves the agent without context for tool selection.

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