Things MCP

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

Annotations include 'openWorldHint: true', indicating the tool can create new resources, which aligns with the description's 'Create a new project'. The description adds value by specifying supported fields and mentioning 'initial to-dos', but does not disclose behavioral traits like permissions needed, rate limits, or side effects (e.g., how areaId/area precedence works). No contradiction with annotations exists.

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 that front-loads the core action ('Create a new project') and enumerates supported fields without redundancy. It avoids unnecessary words, though it could be slightly more structured (e.g., separating core vs. optional features) for optimal clarity.

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 13 parameters with full schema coverage and no output schema, the description adequately covers the tool's purpose and key inputs. However, it lacks context on usage guidelines, behavioral details (e.g., error handling), and output expectations, making it incomplete for a mutation tool with many options. Annotations provide some support but not full transparency.

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 each parameter well-documented in the schema (e.g., 'when' includes format examples). The description lists key parameters (title, notes, when/deadline, tags, area, to-dos) but does not add significant meaning beyond the schema, such as explaining interactions (e.g., areaId vs. area) or constraints. Baseline 3 is appropriate given high 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 specific action ('Create a new project') and resource ('in Things'), distinguishing it from sibling tools like 'add-todo' or 'update-project'. It explicitly lists the supported fields (title, notes, dates, tags, area, to-dos), making the purpose unambiguous and differentiated.

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 'add-todo' for individual tasks or 'update-project' for modifications. It lacks context about prerequisites (e.g., whether an area must exist) or exclusions (e.g., not for bulk operations), offering only a functional statement without usage boundaries.

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