file_exists

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

The annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds no behavioral detail beyond that. It does not disclose return value semantics, error behavior for missing paths, or how unreadable files are handled.

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 very short and front-loaded, putting the key verb and resource first. The bilingual repetition is slightly redundant but does not meaningfully harm clarity or add bloat.

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 one-parameter read-only predicate, the schema and annotations cover the essential input and safety constraints. The description sufficiently conveys the tool's behavior, and although it does not explicitly state the boolean return, the predicate semantics make it clear enough for an agent.

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 input schema fully documents the single 'path' parameter as an absolute file path, so the description does not need to repeat it. The description adds no additional parameter context, which matches the baseline for 100% schema description coverage.

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 a specific verb and resource: 'Check whether a file exists.' It is easy to distinguish from sibling file tools like read_text_file or get_file_info by its predicate nature, though it does not explicitly name or contrast those alternatives.

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?

There is no guidance about when to use this tool versus alternatives. The sibling list contains many file-related tools, but the description does not say, for example, to use this as a precondition before reading or copying a file, nor does it mention any alternative.

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