Connect your FastAPI endpoints as Relevance AI tools for agents.

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1. Create an account and install Relevance AI

Before you get started, make sure you create an account and install Relevance AI:
  1. Sign up for a free account at https://app.relevanceai.com and then login to your Relevance AI account.
  2. Install the Relevance AI library in a Python 3 environment
pip install relevanceai

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2. Log in to Relevance AI

Python
import relevanceai as rai
rai.login()
You can create a key at the bottom of the page here: https://app.relevanceai.com/login/sdk instead of rai.login() you can also set environmental variables to automatically login: 
SET RELEVANCE_API_KEY=RELEVANCE_API_KEY
SET RELEVANCE_REGION=RELEVANCE_REGION
SET RELEVANCE_PROJECT=RELEVANCE_PROJECT

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3. Connect FastAPI

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3.1 Connect

The main function to connect your fastapi endpoints to Relevance AI is connect_tools:
  • the PUBLIC_URL is the public url to connect to your fastapi.
  • the app.routes is the FastAPI’s app = FastAPI()
Python
from relevanceai.connect.fastapi.tools import connect_tools
connect_tools(app.routes, PUBLIC_URL)
Here is an example in the context of FastAPI code.
Python
PUBLIC_URL = "https://where_my_api_is_hosted.com/"

from fastapi import FastAPI
app = FastAPI()

#YOUR APP CODE#

from relevanceai.connect.fastapi.tools import connect_tools
connect_tools(app.routes, PUBLIC_URL)
If you are working off a local computer, use ngrok to get a public url. pip install pyngrok
Python
from fastapi import FastAPI
app = FastAPI()

#YOUR APP CODE#

#add this for ngrok
from pyngrok import ngrok
PUBLIC_URL = ngrok.connect(8000).public_url

from relevanceai.connect.fastapi.tools import connect_tools
connect_tools(app.routes, PUBLIC_URL)
Add nest_asyncio if you are in a notebook environment. pip install nest-asyncio
Python
import nest_asyncio
nest_asyncio.apply()

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3.2 Defining the endpoint and tool

  • @app.post(name=..., description=...). The name and description of the endpoint becomes the same name and description of the Tool. This is crucial when a tool is equipped to an agent since its used in the prompt for agents.
  • message : str = Query(..., description="message from user") The typing and description of endpoint parameters is automatically used when setting the user inputs for the Tool.
Python
class HelloWorldParams(BaseModel):
    message : str = Query(..., title="Message", description="message from user")

class HelloWorldResponse(BaseModel):
    reply : str

def hello_world(prompt):
    return {"reply" : "hello world"}

#The name and description below is the Tool name and description.
@app.post("/hello_world", name="Hello World", description="Reply always with hello world", response_model=HelloWorldResponse)
def hello_world_api(commons: HelloWorldParams):
    return hello_world(commons.message)

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3.3 Deploy

Once you deploy your FastAPI endpoint. You should be able to see the end point show up as a Tool in your Tools list. It should also have a “SDK” badge on it.

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Example of a full code:

Python
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi import APIRouter, Query
from pydantic import BaseModel
from typing import List

#create FastAPI app
app = FastAPI()
app.add_middleware(
    CORSMiddleware,
    allow_origins=['*'],
    allow_credentials=True,
    allow_methods=['*'],
    allow_headers=['*'],
)

class HelloWorldParams(BaseModel):
    message : str = Query(..., title="Message", description="message from user")

class HelloWorldResponse(BaseModel):
    reply : str

def hello_world(prompt):
    return {"reply" : "hello world"}

@app.post("/hello_world", name="Hello World", description="Reply always with hello world", response_model=HelloWorldResponse)
def hello_world_api(commons: HelloWorldParams):
    return hello_world(commons.message)

#If you are deploying the api from a local computer use ngrok to expose a public url.
from pyngrok import ngrok
PUBLIC_URL = ngrok.connect(8000).public_url

#This will create a Tool in Relevance AI that will call your API endpoint
from relevanceai.connect.fastapi.tools import connect_tools
connect_tools(app.routes, PUBLIC_URL)