Fetch Yahoo Finance ETF or mutual fund details by symbol, including profile, top holdings, equity/bond breakdown, and sector weights.
Yahoo Finance fund data. Returns fund profile, top holdings, equity/bond holdings, and sector weighting modules for ETF and mutual fund symbols.
| Name | Required | Description | Default |
|---|---|---|---|
| symbol | Yes | Yahoo Finance symbol such as SPY |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided. The description does not disclose behavioral traits such as being read-only, authentication needs, or rate limits, leaving the agent with insufficient transparency for a data retrieval tool.
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 single-sentence description is concise and front-loaded with purpose, but lacks structured formatting like bullet points. It is efficient without being wasteful.
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 no output schema, the description lists the returned modules (fund profile, top holdings, etc.) and specifies symbol types. It covers the essential context for a simple parameter and data retrieval tool.
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 coverage is 100% with a single parameter 'symbol' described as 'Yahoo Finance symbol such as SPY'. The description adds no further meaning beyond the schema, so baseline 3 is appropriate.
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 it returns 'fund profile, top holdings, equity/bond holdings, and sector weighting modules' specifically for ETF and mutual fund symbols, distinguishing it from sibling tools like yahoo_finance_ticker_info or yahoo_finance_ticker_quote.
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 implies usage for ETF and mutual fund symbols but provides no explicit guidance on when to use this tool versus alternatives, nor does it mention when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.