Fetch consumer price index data from Alpha Vantage for economic analysis and market research.
Fetch consumer price index
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "cpi"
}
}| Name | Required | Description | Default |
|---|---|---|---|
| interval | No | ||
| datatype | No |
Changes observed during successful MCP inspections.
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. 'Fetch' implies a read operation, but there's no information about authentication requirements, rate limits, data freshness, error conditions, or what the return format looks like. This is inadequate for a tool with parameters.
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 maximally concise at just three words. It's front-loaded with the core purpose and wastes no space on unnecessary elaboration. For such a simple statement, this is perfectly structured.
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 a 2-parameter tool with no annotations, 0% schema description coverage, and no output schema, the description is completely inadequate. It doesn't explain what the tool returns, how to use the parameters, or any behavioral characteristics. This leaves the agent with insufficient information to use the tool effectively.
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?
The schema has 0% description coverage for both parameters (interval and datatype), and the tool description provides absolutely no information about what these parameters mean, what values they accept, or how they affect the CPI data fetched. This leaves both parameters completely undocumented.
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 'Fetch consumer price index' clearly states the verb ('fetch') and resource ('consumer price index'), making the purpose immediately understandable. However, it doesn't differentiate this tool from its many siblings (like 'inflation' or other economic indicators), which would require a 5.
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. With 100+ sibling tools including 'inflation' and other economic indicators, there's no indication of what makes 'cpi' distinct or when it should be preferred over similar tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.