Fabits MCP Server

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

No annotations are provided, so the description carries full burden. It mentions 'invest' which implies a financial transaction, but doesn't disclose critical behavioral traits like whether this requires authentication, confirmation steps, transaction fees, or what happens on success/failure. This is inadequate for a tool that likely involves money movement.

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 with no wasted words. It's appropriately sized and front-loaded with the core action, making it easy to parse 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 this is a financial investment tool with no annotations and no output schema, the description is incomplete. It doesn't address behavioral aspects like transaction processing, error handling, or return values, which are crucial for such an operation.

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 parameters thoroughly. The description doesn't add any meaning beyond what's in the schema (e.g., it doesn't explain basket selection logic or amount constraints), meeting the baseline for high coverage.

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 'Invest in a basket of funds' clearly states the action (invest) and resource (basket of funds), but it's vague about the specific investment type. It doesn't distinguish from siblings like 'fabits_invest_basket_onetime' or 'fabits_invest_basket_sip' which suggests different investment methods.

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 siblings like 'fabits_invest_basket_onetime' and 'fabits_invest_basket_sip', the description doesn't explain whether this is for one-time investments, SIPs, or another method, leaving usage unclear.

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