MCP Appium Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions scrolling until visibility is achieved, implying iterative attempts, but does not detail critical behaviors such as success/failure conditions, timeouts, error handling, or interaction with the UI state. For a tool with no annotations, this is insufficient to guide 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 extremely concise and front-loaded with a single, clear sentence: 'Scroll until an element becomes visible.' It wastes no words and directly communicates the core functionality, making it easy for an agent to parse and understand 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 complexity of a scrolling tool with 4 parameters, no annotations, and no output schema, the description is incomplete. It lacks information on behavioral outcomes, error cases, and how parameters interact, which is crucial for an agent to invoke the tool correctly in a testing or automation context. The high schema coverage helps, but the description does not compensate for the missing behavioral and output details.

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%, meaning all parameters are documented in the schema itself. The description does not add any semantic details beyond what the schema provides (e.g., it doesn't explain how 'selector' interacts with 'strategy' or what happens if 'maxScrolls' is exceeded). With high schema coverage, the baseline score of 3 is appropriate, as the description adds no extra value but doesn't detract either.

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: 'Scroll until an element becomes visible.' It specifies the action (scroll) and the goal (make an element visible), which is specific and actionable. However, it does not explicitly differentiate from sibling tools like 'scroll-screen' or 'wait-for-element,' which might have overlapping functionality, so it falls short of 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 does not mention scenarios where scrolling is necessary, prerequisites like element existence, or comparisons to siblings such as 'scroll-screen' (which might scroll without targeting an element) or 'wait-for-element' (which might wait without scrolling). This lack of context leaves the agent without clear usage instructions.

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