How do I give an OpenAI Agents SDK agent access to fund data?

Function tool (Python)

python
# pip install openai-agents fundfacts
from agents import Agent, Runner, function_tool
from fundfacts import FundFacts
​
ff = FundFacts()  # reads FUNDFACTS_API_KEY
​
@function_tool
def fund_facts(isin: str) -> dict:
    """Current factsheet for a fund or ETF ISIN: name, TER, 1-7 risk, category, top holdings, sector/country split, returns, as-of date."""
    f = ff.get_fund(isin)
    d = f["data"]
    return {"name": f["name"], "ter": d["headlineMetrics"]["ter"], "risk": d["riskRating"], "category": d["profile"]["category"],
            "top_holdings": d["topHoldings"][:10], "sectors": d["sector"][:8], "countries": d["geography"][:8],
            "calendar_returns": d["calendarReturns"], "as_of": d["dataAsOf"]}
​
agent = Agent(name="Fund analyst", instructions="Answer with figures from the tool and always state as_of. Empty fields are 'not disclosed'.", tools=[fund_facts])
print(Runner.run_sync(agent, "Compare the cost and sector mix of IE00B4L5Y983 and IE00B3RBWM25").final_output)

Hosted MCP tool

The Agents SDK and the Responses API can call a remote MCP server on your behalf; no wrapper code:

python
from agents import Agent, HostedMCPTool
​
agent = Agent(
    name="Fund analyst",
    tools=[HostedMCPTool(tool_config={
        "type": "mcp",
        "server_label": "fundfacts",
        "server_url": "https://fundfactsapi.com/api/mcp",
        "headers": {"Authorization": "Bearer ffk_..."},
        "require_approval": "never",
    })],
)

typescript
// npm install @openai/agents
import { Agent, hostedMcpTool, run } from "@openai/agents";
​
const agent = new Agent({
  name: "Fund analyst",
  instructions: "Quote dataAsOf with every figure.",
  tools: [hostedMcpTool({ serverLabel: "fundfacts", serverUrl: "https://fundfactsapi.com/api/mcp", headers: { Authorization: `Bearer ${process.env.FUNDFACTS_API_KEY}` } })],
});
const result = await run(agent, "How much do IE00B4L5Y983 and IE00B3RBWM25 overlap?");
console.log(result.finalOutput);

The MCP server exposes six tools, each counted like the REST endpoint it wraps: get_fund (ISIN → the full factsheet payload), search_funds (name → ISINs, free), compare_funds (side-by-side table for several ISINs), analyze_portfolio (weighted look-through of a list of positions, Pro and above), fund_overlap (shared holdings between funds, Pro and above) and get_scpi (French SCPI data by name or ISIN). Authentication is the same bearer API key as the REST API, sent as an Authorization header.

Production notes

Give function tools a 300-second timeout for cold ISINs, cache by ISIN until expiresAt, and tell the agent that a 404 means "not a covered fund". Tool calls cost one request per ISIN answered, the same as REST.