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 OTP verification as a prerequisite, which adds some behavioral context, but it doesn't disclose critical traits like whether this is a read-only or destructive operation, authentication needs, rate limits, or what happens on success/failure. For a financial transaction tool, this is a significant gap.

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 gets straight to the point without unnecessary words. It's appropriately sized for the tool's complexity, though it could be slightly more structured by front-loading key details more explicitly.

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 transaction tool with no annotations and no output schema, the description is incomplete. It lacks details on behavioral traits, error handling, return values, and differentiation from siblings. While concise, it doesn't provide enough context for safe and effective use by 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 already documents all 5 parameters thoroughly. The description doesn't add any additional meaning or context beyond what's in the schema, such as explaining relationships between parameters or usage nuances. Baseline 3 is appropriate when the schema does the heavy lifting.

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 ('Complete UPI lumpsum investment') and the resource ('after OTP verification'), making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'fabits_invest_lumpsum_upi' which might handle earlier steps, leaving some ambiguity about the exact scope.

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 minimal guidance by implying usage after OTP verification, but it doesn't specify when to use this tool versus alternatives like 'fabits_invest_lumpsum_upi' or prerequisites beyond OTP. No explicit when-not-to-use or alternative recommendations are given, leaving gaps in usage context.

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