filesystem-mcp

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 mentions optional stats and recursive listing, but doesn't describe important behavioral aspects like whether this is a read-only operation (implied but not stated), what permissions are required, how results are formatted, whether there are rate limits, or if it handles symbolic links. The description is insufficient for a tool with no annotation coverage.

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 extremely concise at just two sentences with zero wasted words. It's front-loaded with the core purpose and efficiently covers the two key optional features. Every sentence earns its place by adding meaningful information.

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 file listing tool with no annotations and no output schema, the description is incomplete. It doesn't explain what the output looks like (list format, what fields are included), how errors are handled, or important constraints. Given the complexity of file system operations and the lack of structured metadata, the description should provide more complete context.

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%, so the schema already fully documents all three parameters. The description adds minimal value by mentioning 'stats' and 'recursively' which map to 'include_stats' and 'recursive' parameters, but provides no additional semantic context beyond what's in the schema. This meets the baseline for high schema 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 the tool's purpose as 'List files/directories' with a specific verb and resource. It distinguishes itself from siblings like 'search_files' by focusing on listing rather than searching, but doesn't explicitly contrast with 'stat_items' which also provides file information. The description is clear but lacks explicit sibling differentiation.

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 when to choose 'list_files' over 'search_files' for finding files, or when 'stat_items' might be more appropriate for detailed statistics. There's no context about prerequisites or typical use cases.

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