Things App MCP

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

Annotations already declare readOnlyHint=true, so the agent knows this is safe. The description adds valuable context about implementation ('Uses AppleScript') and platform restriction ('macOS only'), which aren't covered by annotations. However, it doesn't describe return format, pagination, or error behavior.

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 concise sentences with zero waste. First sentence states core functionality, second adds crucial implementation and platform constraints. Every word earns its place in this efficiently structured description.

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 simple read operation with good annotations (readOnlyHint) and full schema coverage, the description provides adequate context. The macOS/AppleScript constraint is particularly valuable. Without output schema, it could mention return format, but the core functionality is well-covered.

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%, with the single parameter 'days' fully documented in the schema. The description doesn't add any parameter-specific information beyond what's in the schema, so baseline 3 is appropriate given the schema does the heavy lifting.

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 verb ('Get') and resource ('recently modified to-dos'), making the purpose immediately understandable. It distinguishes from siblings like 'get-todos' by specifying 'recently modified' scope, though it doesn't explicitly contrast with 'search-todos' or 'get-todo-by-id'.

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 implies usage context with 'recently modified' and platform restriction 'macOS only', but doesn't explicitly state when to use this vs alternatives like 'get-todos' (all todos) or 'search-todos' (filtered search). No guidance on prerequisites or exclusions beyond platform.

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