Android MCP

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

Annotations provide destructiveHint=true, indicating this is a mutation operation. The description adds that it performs a 'long click' (implying a press-and-hold action), which gives behavioral context beyond the annotation. However, it doesn't specify duration, side effects, or error conditions, leaving gaps in 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 a single, efficient sentence with no wasted words. It's front-loaded with the core action and parameters, making it easy to parse 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 destructiveHint annotation and lack of output schema, the description is incomplete. It doesn't cover what a 'long click' entails (e.g., duration, visual feedback), success/failure responses, or dependencies like device state. For a UI interaction tool with mutation behavior, this leaves significant gaps.

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 0%, so the schema only documents parameter types (integers for x and y). The description adds that these are 'specific coordinate' parameters, providing basic semantics. However, it doesn't explain coordinate systems (e.g., screen pixels, relative positioning), units, or valid ranges, which is insufficient given the low 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 action ('Long click') and target ('on a specific coordinate'), which is a specific verb+resource combination. It distinguishes from sibling 'Click' by specifying a 'long' click, though it doesn't explicitly contrast with other UI interaction tools like 'Drag' or 'Swipe'.

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 like 'Click' or other UI interaction tools. It doesn't mention prerequisites (e.g., device connection), use cases for long clicks, or exclusions, leaving the agent to infer usage context.

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