Compute the annualized return (XIRR) from a series of dated cash flows, treating negative amounts as investments and positive amounts as redemptions or current value.
XIRR for dated cash flows.
Each item: {"date": "YYYY-MM-DD", "amount": -10000}. Investments are negative, redemptions / current value positive.
| Name | Required | Description | Default |
|---|---|---|---|
| cashflows | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Since no annotations were provided, the description carries the full burden. It excels here by defining the sign convention for financial flows (Investments are negative, redemptions positive), which is critical behavioral information not captured in the generic input schema.
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 definition is highly efficient, using two sentences to provide the core function and all necessary input constraints (sign convention and structure) without introducing fluff.
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 tool requiring a complex nested array of specific financial objects, the description provides all necessary structural and behavioral information (sign conventions, required fields, date format). Since an output schema exists, the focus on input completeness is appropriate and fully satisfied.
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?
Given the input schema provided almost zero structural information (0% coverage), the description is vital. It explicitly defines the required properties for each item in the 'cashflows' array (date and amount) and specifies the expected date format.
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 purpose is immediately clear and identifies the specific calculation (XIRR) and its required data structure (dated cash flows). It is distinct from the other financial calculation tools in the sibling list.
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 clear input format constraints (date and amount) which implicitly guides usage. While it doesn't explicitly compare itself to all siblings, the strict requirement for 'dated' flows sets a clear usage context.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.