BetterTouchTool MCP Server

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, indicating a safe, non-mutating operation. The description adds valuable context by explaining the types of variables (built-in and user-defined) and specifying the return value ('Current value of the variable'), which enhances understanding beyond the annotations. No contradictions with annotations are present.

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 well-structured and front-loaded, with the core purpose in the first sentence, followed by context and a clear Args/Returns breakdown. Every sentence adds value without redundancy, making it efficient and easy to parse for an AI agent.

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 low complexity (1 parameter), rich annotations (readOnlyHint, idempotentHint), and the presence of an output schema (which handles return values), the description is largely complete. It covers the tool's purpose, variable types, and parameter basics. However, it could improve by addressing potential errors (e.g., if a variable doesn't exist) or connection requirements, slightly reducing completeness.

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?

The schema description coverage is 0%, meaning parameters are undocumented in the schema. The description compensates by listing 'Variable name and type (string or number)' in the Args section, which clarifies the purpose of the single parameter 'params'. However, it doesn't detail the nested structure (e.g., connection configuration) or provide examples, leaving some gaps in parameter understanding.

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: 'Get the value of a BTT variable.' It specifies the verb ('Get') and resource ('BTT variable'), and distinguishes it from siblings like btt_set_variable. However, it doesn't explicitly differentiate from other read operations like btt_get_trigger or btt_get_triggers, which prevents 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 implied usage context by mentioning 'BTT has many built-in variables (like BTTActiveAppBundleIdentifier) and supports user-defined variables,' which suggests when this tool is applicable. However, it lacks explicit guidance on when to use this tool versus alternatives like btt_get_trigger for different data types, or prerequisites for accessing variables.

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