Fabits MCP Server

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

No annotations are provided, so the description carries the full burden. It mentions 'place a one-time lumpsum investment order,' implying a write operation, but doesn't disclose critical behavioral traits such as authentication needs, rate limits, transaction confirmation, or error handling. For a financial tool with no annotations, this is a significant gap in transparency.

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, clear sentence that is front-loaded and wastes no words. It efficiently conveys the core purpose without unnecessary elaboration, making it easy to parse and understand 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 complexity of a financial investment tool with no annotations and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., side effects, returns), doesn't explain the outcome or confirmation process, and fails to address how it fits among sibling tools, leaving significant gaps for an AI agent.

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%, so the schema fully documents the three parameters (user_id, fund_id, amount). The description adds no additional meaning beyond what's in the schema, such as format details or constraints. With high schema coverage, a baseline score of 3 is appropriate as the description doesn't compensate but doesn't need to.

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 ('place a one-time lumpsum investment order'), which is specific and includes the resource ('investment order'). However, it doesn't differentiate from sibling tools like 'fabits_invest_lumpsum_upi' or 'fabits_invest_basket_onetime', which might also handle one-time investments, leaving some ambiguity about when to choose this specific tool.

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 guidance is provided on when to use this tool versus alternatives. With multiple investment-related siblings (e.g., 'fabits_invest_lumpsum_upi', 'fabits_invest_basket_onetime'), the description lacks context about prerequisites, timing, or distinctions, offering no help in tool selection.

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