file_info

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

Without annotations, the description carries the transparency burden. It discloses key traits: it checks existence, returns size and modification time, and does not read content. This signals a safe, non-destructive operation. However, it does not specify behavior for nonexistent paths or error handling, which is a minor gap for a file inspection 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?

The description is a single, tightly worded sentence that front-loads the core purpose and includes the key scoping detail ('without reading it'). No wasted words.

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 metadata tool with no output schema, the description covers the essentials: existence check, size, modification time, and the fact that content is not read. It does not detail the return structure or error cases, but given the tool's simplicity, it is reasonably complete for an agent to select and invoke it.

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?

Schema description coverage is 100%, with 'path' described as 'Path to inspect.' and 'workspace' as 'Workspace alias. Defaults to the active workspace.' The description adds no additional parameter information beyond the schema, so the baseline of 3 applies.

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 identifies the tool as a metadata inspection tool: 'Check whether a path exists and get its size and modification time.' The verb 'check' and explicit mention of 'without reading it' distinguish it from siblings like read_file and list_dir, making its purpose 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 phrase 'without reading it' implies usage for metadata-only needs, but no explicit alternatives or exclusions are named. The description provides context for when to use (checking existence and metadata) but does not directly contrast with read_file or other siblings.

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