Suggest some tools for knowledge based ai systems preferably free

There are several tools and platforms you can use to build knowledge-based AI systems, many of which offer free tiers or are open-source. Here are some notable options: 1. **Natural Language Processing (NLP) Libraries:** - **spaCy:** An open-source NLP library in Python that provides pre-trained models for various languages and enables tasks like part-of-speech tagging, named entity recognition, and dependency parsing. - **NLTK (Natural Language Toolkit):** Another Python library for NLP tasks, providing easy-to-use interfaces to over 50 corpora and lexical resources. - **Transformers by Hugging Face:** A library that provides state-of-the-art pre-trained models for NLP tasks and supports fine-tuning for specific tasks. 2. **Knowledge Graphs and Semantic Web:** - **Apache Jena:** A framework for building semantic web and linked data applications, including a triple store and a SPARQL query engine. - **Neo4j:** A popular graph database that can represent knowledge graphs. It offers free community editions with limited features. - **GraphDB:** An RDF triplestore for semantic graph databases that offers a free version. 3. **Inference Engines:** - **Apache Jena (also serves as an inference engine):** It allows reasoning over RDF data and supports various rule-based reasoning. - **CLIPS:** A public domain software tool for building expert systems, which includes a rule-based inference engine. 4. **Ontology Editors:** - **Protégé:** An open-source ontology editor and framework for building knowledge-based applications. It allows users to create and manage ontologies and supports various reasoning mechanisms. 5. **Machine Learning Frameworks:** - **TensorFlow:** An open-source machine learning library that can be used to develop neural networks and other models for inferencing. - **PyTorch:** Another popular machine learning library known for its flexibility and ease of use for research and application. 6. **Chatbot Frameworks:** - **Rasa:** An open-source conversational AI framework that allows developers to build contextual chatbots that can process and respond to user inputs. - **BotPress:** An open-source platform for building chatbots, based on a modular system that allows for easy customization. 7. **Collaborative Knowledge Base Platforms:** - **MediaWiki:** The software that powers Wikipedia, allowing you to create your own knowledge base with user contributions. - **TiddlyWiki:** An open-source, non-linear notebook for capturing and organizing complex information, great for personal knowledge management. 8. **Data Annotation Tools:** - **Prodigy:** A machine learning annotation tool that supports active learning. While not free, it offers a trial version. - **Label Studio:** An open-source data labeling tool that supports text, audio, image, and video annotation. 9. **Visualization Tools:** - **Gephi:** An open-source network visualization tool that can be used to visualize knowledge graphs. - **Cytoscape:** Mainly used for biomolecular research but can visualize complex networks and integrate with bioinformatics databases. These tools can form part of a comprehensive knowledge-based AI system depending on the specific requirements and use cases you are targeting. Most of these solutions provide extensive documentation and community support, making them easier to implement and customize for your needs.