Need to inspect app files? Lists Documents, Library, and tmp contents from development-signed iOS apps.
List files in an app's data container (Documents, Library, tmp…). Works for development-signed apps only.
| Name | Required | Description | Default |
|---|---|---|---|
| device | No | Device UDID or name substring. Defaults to the select_device choice, then IOS_DEVICE_MCP_DEVICE, else the single USB-connected device. | |
| bundleId | Yes | ||
| subdirectory | No | e.g. Documents |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the full burden. It discloses the significant dev-signed-app constraint, but says nothing about whether the app must be installed or running, whether output is recursive, or how large listings behave.
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?
Two short sentences, both earning their place; the core action is front-loaded and the constraint follows. No filler or repetition of the tool name.
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?
With no output schema and no annotations, the description should say more about the return shape (file names? sizes? paths?) and the required app state. The dev-signed caveat is the one behavioral piece covered; the rest of the picture is missing.
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 coverage is 67%: device and subdirectory are documented, but bundleId is not. The description marginally enriches subdirectory by naming Documents, Library and tmp as valid containers, but adds nothing about bundleId or the device fallback chain already in the schema.
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 ('List files in an app's data container') and clarifies scope with example container directories. It does not distinguish itself from the nearest sibling, pull_file, which also deals with on-device files, so an agent must infer the difference.
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 clause 'Works for development-signed apps only' gives a real precondition for use, which is implied guidance. However, there is no explicit when-to-use vs. pull_file or list_apps, and no statement of what happens with a release-signed bundle.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.