Amazing Marvin MCP

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

With no annotations provided, the description carries full burden for behavioral disclosure. While 'Mark as completed' implies a mutation operation, it doesn't specify whether this requires authentication, what happens to the task status, if the action is reversible, or any side effects like notifications or updates to related data. This is inadequate for a mutation tool with zero annotation coverage.

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 directly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded with the core functionality.

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 mutation tool with 2 parameters (one required), 0% schema description coverage, no annotations, and no output schema, the description is insufficient. It doesn't explain what the tool returns, how errors are handled, or provide enough context about parameters and behavior for safe invocation.

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 0%, meaning neither parameter has descriptions in the schema. The tool description provides no information about what 'item_id' represents (e.g., task identifier format) or what 'timezone_offset' does (e.g., affects completion timestamp). The description fails to compensate for the schema's lack of documentation.

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 action ('Mark as completed') and the resource ('a task in Amazing Marvin'), providing a specific verb+resource combination. However, it doesn't differentiate this tool from its sibling 'batch_mark_done', which appears to serve a similar purpose but for multiple tasks.

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 'batch_mark_done' for multiple tasks or other task management tools in the sibling list. There's no mention of prerequisites, context, or exclusions for usage.

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