Introduction
For trading agents, decision latency is a first-class concern. Every millisecond between market data arriving and a trade executing is a window for the market to move against you. This makes inference speed — not just model capability — a critical variable in agent architecture choices.
Fireworks AI offers the fastest open-source model inference available today, routinely achieving sub-100ms time-to-first-token for Llama-class models. For an agent running a 3-tool-call reasoning loop, Fireworks can complete the full cycle in 1–2 seconds. The same loop with GPT-4o typically takes 4–6 seconds. In markets that move in milliseconds, that difference matters.
This guide shows how to build a live crypto trading agent using Fireworks AI for inference and Purple Flea's trading API for execution — in under 30 minutes.
Why Fireworks for Trading Agents
- Sub-100ms inference for Llama 3.1 8B and Mixtral 8x7B — the fastest open-source inference tier available
- OpenAI-compatible API — just change
base_urlandapi_key; your existing code works unchanged - 150+ models including DeepSeek-V3, Qwen 2.5 72B, Llama 3.3 70B, and Mixtral 8x22B
- Cost-effective pricing — $0.20–$0.90 per 1M tokens, making dense agent loops financially viable
- Serverless by default — no infrastructure to manage, scales automatically with demand
Setup
Install the required packages:
pip install openai requests
Get your Fireworks API key at fireworks.ai — the free tier includes $1 of credits which is sufficient to run dozens of agent loops for testing. Get your Purple Flea API key at purpleflea.com/register.
Tool Definitions
Define the tools the agent can call. We start with two: a market data tool and a trade execution tool. Both map to Purple Flea API endpoints:
tools = [
{
"type": "function",
"function": {
"name": "get_market_data",
"description": "Get current market price, 24h volume, and recent price change for a crypto perpetual futures symbol",
"parameters": {
"type": "object",
"properties": {
"symbol": {
"type": "string",
"description": "Trading symbol e.g. BTC-PERP, ETH-PERP, SOL-PERP"
}
},
"required": ["symbol"]
}
}
},
{
"type": "function",
"function": {
"name": "trade",
"description": "Execute a perpetual futures trade. Use only when you have a clear directional view with supporting data.",
"parameters": {
"type": "object",
"properties": {
"symbol": {
"type": "string",
"description": "Trading symbol e.g. BTC-PERP"
},
"side": {
"type": "string",
"enum": ["long", "short"],
"description": "Direction of the trade"
},
"size_usd": {
"type": "number",
"description": "Position size in USD"
}
},
"required": ["symbol", "side", "size_usd"]
}
}
}
]
Full Agent Implementation
The following agent uses Fireworks for inference, Purple Flea for market data and trade execution, and implements the standard tool-calling loop:
from openai import OpenAI
import requests
import json
# Fireworks client — drop-in replacement for OpenAI client
fw_client = OpenAI(
base_url="https://api.fireworks.ai/inference/v1",
api_key="your-fireworks-api-key"
)
PF_KEY = "your-purple-flea-key"
HEADERS = {"Authorization": f"Bearer {PF_KEY}", "Content-Type": "application/json"}
def execute_tool(name: str, args: dict) -> dict:
"""Route tool calls to the appropriate Purple Flea API endpoint"""
if name == "get_market_data":
r = requests.get(
f"https://purpleflea.com/api/v1/markets/{args['symbol']}/price",
headers=HEADERS
)
return r.json()
elif name == "trade":
r = requests.post(
"https://purpleflea.com/api/v1/trade",
json={
"symbol": args["symbol"],
"side": args["side"],
"size": args["size_usd"],
"leverage": 2
},
headers=HEADERS
)
return r.json()
return {"error": f"Unknown tool: {name}"}
def run_agent():
messages = [
{
"role": "system",
"content": (
"You are a crypto trading agent with access to live market data and trade execution. "
"Check BTC-PERP and ETH-PERP prices and recent changes. "
"If you see a clear directional signal (e.g. one asset breaking higher with volume), "
"execute a small long or short position. If no clear signal, do nothing and explain why. "
"Always prioritize capital preservation over opportunity capture."
)
},
{
"role": "user",
"content": "Analyze the current market conditions and take action if appropriate."
}
]
print("Running agent loop...")
# Tool-calling loop — continues until model stops requesting tools
while True:
response = fw_client.chat.completions.create(
model="accounts/fireworks/models/llama-v3p1-70b-instruct",
messages=messages,
tools=tools,
tool_choice="auto",
temperature=0.2,
max_tokens=1024
)
msg = response.choices[0].message
messages.append(msg)
# No more tool calls — agent has reached a decision
if not msg.tool_calls:
print(f"\nAgent decision: {msg.content}")
break
# Execute each requested tool call
for tc in msg.tool_calls:
tool_args = json.loads(tc.function.arguments)
print(f"Calling {tc.function.name}({tool_args})")
result = execute_tool(tc.function.name, tool_args)
print(f"Result: {result}")
messages.append({
"role": "tool",
"tool_call_id": tc.id,
"content": json.dumps(result)
})
run_agent()
Temperature matters for trading agents. Use low temperature (0.1–0.3) for trading decisions — you want deterministic, analytical reasoning, not creative generation. Higher temperatures produce more varied responses which introduces randomness into trade decisions you do not want.
Model Recommendations
Fireworks hosts 150+ models. For trading agents, these four are the strongest options:
Latency Benchmarks
Approximate time-to-first-token and total agent loop time (3 tool calls) across model providers:
| Model | Provider | TTFT | Full Agent Loop (3 tools) |
|---|---|---|---|
| Llama 3.1 8B | Fireworks | ~80ms | ~0.8s |
| Llama 3.1 70B | Fireworks | ~200ms | ~1.5s |
| Mixtral 8x22B | Fireworks | ~150ms | ~1.2s |
| GPT-4o | OpenAI | ~800ms | ~5s |
| Claude Sonnet | Anthropic | ~600ms | ~4s |
For most trading strategies, the latency difference between Fireworks Llama 70B (1.5s loop) and GPT-4o (5s loop) is not the deciding factor — the quality of the reasoning is. However, for agents running many parallel loops or reacting to fast-moving market events, the 3–4x latency advantage of Fireworks compounds significantly.
Extending the Agent
The base agent above is deliberately minimal. Here are natural extensions to add:
- More tools: Add
get_portfolio_balance,close_position, andget_funding_ratefor a more complete trading loop - Market context injection: Pass recent price history, technical indicators, and funding rates in the system prompt as structured data
- Multi-asset coverage: Have the agent check 5–10 symbols and rank them by conviction before picking which to trade
- Memory: Log each decision with reasoning to a database; use recent history to prompt the agent about what it decided previously
- Scheduling: Wrap the agent in a cron job or APScheduler loop to run every 15 minutes continuously
Conclusion
Fireworks AI removes one of the last performance excuses for using closed-source models in trading agents. With sub-200ms inference for 70B-class models and full OpenAI API compatibility, the migration from GPT-4o to Fireworks is a 3-line change that delivers a 3–4x latency improvement and significant cost reduction.
Pair Fireworks with Purple Flea's financial APIs and you have a complete stack: fast reasoning, live market data, instant trade execution, and trustless agent-to-agent payments via escrow — all purpose-built for AI agents.
Get started with the Fireworks AI integration guide, trading API, and full API reference. Register your agent at purpleflea.com/register.