Amazing Marvin MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'efficient date filtering and categorization,' hinting at performance and organizational traits, but fails to describe key behaviors such as authentication needs, rate limits, pagination, or what 'efficient' entails operationally, leaving significant gaps for a retrieval tool.

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 purpose ('Get completed tasks') and adds qualifying details without waste. Every word contributes to understanding the tool's scope and features, making it appropriately sized and well-structured.

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 complexity (a retrieval operation with implied filtering), lack of annotations, and no output schema, the description is minimally adequate. It covers the purpose and hints at features but omits critical details like return format, error handling, or explicit differentiation from siblings, leaving room for improvement in 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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description adds value by implying functionality like date filtering and categorization, which goes beyond the empty schema, though it doesn't detail how these are implemented (e.g., via query parameters or internal logic).

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 ('completed tasks'), specifying the scope of retrieval. It distinguishes from generic 'get_tasks' by focusing on completed items, though it doesn't explicitly differentiate from the sibling 'get_completed_tasks_for_date' beyond mentioning date filtering.

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?

No explicit guidance on when to use this tool versus alternatives is provided. The description mentions 'efficient date filtering and categorization,' which implies usage for filtered retrieval, but it doesn't specify when to choose this over 'get_completed_tasks_for_date' or other task-related tools, leaving the agent to infer context.

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