🟡 LLMs Using Tools
MRKL Systems1 (Modular Reasoning, Knowledge and Language, pronounced "miracle") are a neuro-symbolic architecture that combine LLMs (neural computation) and external tools like calculators (symbolic computation), to solve complex problems.
A MRKL system is composed of a set of modules (e.g. a calculator, weather API, database, etc.) and a router that decides how to 'route' incoming natural language queries to the appropriate module.
A simple example of a MRKL system is a LLM that can
use a calculator app. This is a single module system, where the LLM is the router.
When asked, What is 100*100?
, the LLM can choose to
extract the numbers from the prompt, and then tell the MRKL System to use a calculator
app to compute the result. This might look like the following:
What is 100*100?
CALCULATOR[100*100]
The MRKL system would see the word CALCULATOR
and plug 100*100
into the calculator app.
This simple idea can easily be expanded to various symbolic computing tools.
Consider the following additional examples of applications:
- A chatbot that is able to respond to questions about a financial database by extracting information to form a SQL query from a users' text.
What is the price of Apple stock right now?
The current price is DATABASE[SELECT price FROM stock WHERE company = "Apple" AND time = "now"].
- A chatbot that is able to respond to questions about the weather by extracting information from the prompt and using a weather API to retrieve the information.
What is the weather like in New York?
The weather is WEATHER_API[New York].
- Or even much more complex tasks that depend on multiple datasources, such as the following:
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An Example
I have reproduced an example MRKL System from the original paper, using Dust.tt,
linked here.
The system reads a math problem (e.g. What is 20 times 5^6?
), extracts the numbers and the operations,
and reformats them for a calculator app (e.g. 20*5^6
). It then sends the reformatted equation
to Google's calculator app, and returns the result. Note that the original paper performs prompt tuning on the router (the LLM), but I do not in this example. Let's walk through how this works:
First, I made a simple dataset in the Dust Datasets
tab.
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Then, I switched to the Specification
tab and loaded the dataset using a data
block.
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Next, I created a llm
block that extracts the numbers and operations. Notice how
in the prompt I told it we would be using Google's calculator. The model I use (GPT-3)
likely has some knowledge of Google's calculator from pretraining.
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Then, I made a code
block, which runs some simple javascript code to remove
spaces from the completion.
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Finally, I made a search
block that sends the reformatted equation to Google's calculator.
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Below we can see the final results, which are all correct!
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Feel free to clone and experiment with this playground here.
Notes
MRKL was developed by AI21 and originally used their J-1 (Jurassic 1)2 LLM.
More
See this example of a MRKL System built with LangChain.
- Karpas, E., Abend, O., Belinkov, Y., Lenz, B., Lieber, O., Ratner, N., Shoham, Y., Bata, H., Levine, Y., Leyton-Brown, K., Muhlgay, D., Rozen, N., Schwartz, E., Shachaf, G., Shalev-Shwartz, S., Shashua, A., & Tenenholtz, M. (2022). MRKL Systems: A modular, neuro-symbolic architecture that combines large language models, external knowledge sources and discrete reasoning. ↩
- Lieber, O., Sharir, O., Lentz, B., & Shoham, Y. (2021). Jurassic-1: Technical Details and Evaluation, White paper, AI21 Labs, 2021. URL: Https://Uploads-Ssl. Webflow. Com/60fd4503684b466578c0d307/61138924626a6981ee09caf6_jurassic_ Tech_paper. Pdf. ↩