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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds a comparative cost trait ('cheaper than listing'), which is useful behavioral context beyond the annotations, though it says nothing about the shape of the metadata returned or error behavior for missing paths.

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?

Three short sentences, each earning its place: the first defines the operation and output, the second gives usage rationale, the third anchors the root-selection semantics. The primary purpose is front-loaded.

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 read-only metadata tool with full schema coverage and complete annotations, this is sufficient. Without an output schema, the description helpfully enumerates the returned fields (type, size, modification time) so the agent knows what to expect.

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 all three parameters are already documented in the schema. The description adds only a cross-reference ('Same bundleId root selection as ios_file_list') rather than new syntax or format detail, so the baseline 3 is appropriate.

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?

States a specific verb and resource ('Get metadata for one file or directory on an iOS device') and enumerates the returned fields (type, size, modification time). It also distinguishes itself from the sibling ios_file_list by framing itself as the targeted single-path alternative.

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?

Gives explicit when-to-use conditions: 'cheaper than listing a directory when you already know the path' and 'the way to check a file's size before pulling it.' This directly routes the agent between ios_file_stat, ios_file_list, and ios_file_pull.

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