List Directory with Sizes

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

The annotations already declare readOnlyHint=true, indicating a safe read operation. The description adds valuable behavioral context beyond this: it specifies the output format ('[FILE] and [DIR] prefixes'), the scope constraint ('Only works within allowed directories'), and the tool's utility for structure analysis. While it doesn't mention rate limits or pagination, it provides meaningful operational details that enhance transparency.

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 efficiently structured in three sentences: the first states the core functionality, the second explains output formatting, and the third provides usage context and constraints. Each sentence adds distinct value without redundancy, making it front-loaded and appropriately concise for the tool's complexity.

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 moderate complexity, annotations covering safety, an output schema (implied by context signals), and clear purpose, the description is complete. It covers what the tool does, how results are presented, usage scenarios, and access limitations. No critical gaps exist, as output details are handled by the schema, and annotations cover read-only behavior.

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 50% (only 'sortBy' has a description). The description mentions 'specified path' which aligns with the 'path' parameter but doesn't add details like format or examples. It implies sorting by size but doesn't elaborate beyond the schema's enum. With moderate coverage, the description provides minimal additional parameter semantics, meeting the baseline for adequate but not compensatory value.

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 specific action ('Get a detailed listing'), resource ('files and directories in a specified path'), and key feature ('including sizes'). It explicitly distinguishes this tool from its sibling 'list_directory' by emphasizing size information and formatting details, making the purpose unambiguous and differentiated.

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 clear context for when to use this tool ('useful for understanding directory structure and finding specific files within a directory') and includes an important exclusion ('Only works within allowed directories'). However, it doesn't explicitly compare it to alternatives like 'list_directory' (which presumably lacks sizes) or 'directory_tree' (which might show hierarchy), missing explicit sibling differentiation.

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