Things MCP

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

The description adds value beyond annotations by disclosing platform dependency ('macOS only') and implementation details ('Uses AppleScript'), which aren't covered by the readOnlyHint annotation. However, it lacks information on behavioral traits such as rate limits, error handling, or what 'recently modified' entails (e.g., modification vs. creation). No contradiction with annotations is 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 extremely concise and front-loaded, consisting of just two sentences that efficiently convey the core functionality and key constraints. Every word earns its place, with no wasted information, 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 tool's low complexity (one optional parameter) and the presence of annotations (readOnlyHint), the description is minimally adequate. However, without an output schema, it doesn't explain return values (e.g., format of to-dos), and it lacks details on scope (e.g., all to-dos or filtered). For a read-only tool, it meets basic needs but could be more complete.

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 description doesn't add any parameter-specific information beyond what's in the input schema, which has 100% coverage for the single parameter 'days'. Since the schema fully describes the parameter, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

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 with a specific verb ('Get') and resource ('recently modified to-dos'), making it easy to understand what it does. However, it doesn't explicitly differentiate from sibling tools like 'get-todos' or 'search-todos', which likely 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 some usage context by mentioning 'macOS only' and 'recently modified', which implies when to use it (for recent items on macOS). However, it doesn't offer explicit guidance on when to choose this tool over alternatives like 'get-todos' or 'search-todos', nor does it specify exclusions or prerequisites beyond the OS requirement.

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