list-directory

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

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It implies a read-only operation by using 'List,' but doesn't disclose critical traits like error handling (e.g., what happens if the path doesn't exist), authentication requirements, rate limits, or output format (e.g., list of filenames vs. detailed metadata). This leaves significant gaps for safe and effective use.

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 front-loads the core purpose ('List contents of an FTP directory') with zero wasted words. It's appropriately sized for a simple tool with one parameter and no complex behaviors, making it easy for an agent to parse quickly.

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?

Given the tool's simplicity (1 parameter, no output schema, no annotations), the description is incomplete. It lacks details on output (what 'contents' includes), error cases, and usage context relative to siblings. While concise, it doesn't provide enough information for an agent to use the tool confidently without trial and error, especially with no annotations to fill gaps.

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 the single parameter 'remotePath' fully documented in the schema as 'Path of the directory on the FTP server.' The description adds no additional meaning beyond this, such as path format examples or constraints. Given the high schema coverage, the baseline score of 3 is appropriate, as the description doesn't compensate but doesn't need to.

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 action ('List contents') and target resource ('an FTP directory'), making the purpose immediately understandable. It distinguishes from siblings like 'download-file' or 'create-directory' by focusing on listing rather than file manipulation. However, it doesn't specify what information is listed (e.g., files, subdirectories, metadata), keeping it from a perfect score.

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 doesn't mention prerequisites (e.g., needing an existing directory), exclusions (e.g., not for listing files in a non-directory path), or relationships to siblings like 'download-file' for retrieving specific files. The agent must infer usage from 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.