Amazing Marvin MCP

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool retrieves data ('Get'), implying it's a read operation, but doesn't specify whether it requires authentication, has rate limits, returns real-time or cached data, or what happens on errors. For a tool with zero annotation coverage, this leaves significant behavioral gaps.

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 today's focus items') and adds clarifying detail ('- due items and scheduled tasks'). There is no wasted verbiage or redundancy, making it highly concise 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 simplicity (0 parameters, no output schema, no annotations), the description is adequate but not complete. It explains what the tool does but lacks details on return format, error handling, or behavioral constraints. For a read-only tool with no structured output, more context on the response would be beneficial.

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 tool has 0 parameters, and schema description coverage is 100% (though empty). The description doesn't need to explain parameters, and it appropriately doesn't mention any. This meets the baseline for tools with no parameters, but a 5 would require explicit confirmation of no parameters needed.

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 today's focus items - due items and scheduled tasks'. It specifies the verb ('Get') and resource ('today's focus items'), with additional clarification on what constitutes focus items. However, it doesn't explicitly distinguish this tool from similar siblings like 'get_due_items' or 'get_tasks', which reduces it from 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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, timing considerations, or compare it to siblings like 'get_due_items' or 'get_completed_tasks_for_date'. The user must infer usage from the name and description alone.

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