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docs/api/index.md

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+# API
+
+![api](../images/api.png#only-light)
+![api](../images/api-dark.png#only-dark)
+
+txtai has a full-featured API, backed by [FastAPI](https://github.com/tiangolo/fastapi), that can optionally be enabled for any txtai process. All functionality found in txtai can be accessed via the API.
+
+The following is an example configuration and startup script for the API.
+
+Note: This configuration file enables all functionality. For memory-bound systems, splitting pipelines into multiple instances is a best practice.
+
+```yaml
+# Index file path
+path: /tmp/index
+
+# Allow indexing of documents
+writable: True
+
+# Enbeddings index
+embeddings:
+  path: sentence-transformers/nli-mpnet-base-v2
+
+# Extractive QA
+extractor:
+  path: distilbert-base-cased-distilled-squad
+
+# Zero-shot labeling
+labels:
+
+# Similarity
+similarity:
+
+# Text segmentation
+segmentation:
+    sentences: true
+
+# Text summarization
+summary:
+
+# Text extraction
+textractor:
+    paragraphs: true
+    minlength: 100
+    join: true
+
+# Transcribe audio to text
+transcription:
+
+# Translate text between languages
+translation:
+
+# Workflow definitions
+workflow:
+    sumfrench:
+        tasks:
+            - action: textractor
+              task: url
+            - action: summary
+            - action: translation
+              args: ["fr"]
+    sumspanish:
+        tasks:
+            - action: textractor
+              task: url
+            - action: summary
+            - action: translation
+              args: ["es"]
+```
+
+Assuming this YAML content is stored in a file named config.yml, the following command starts the API process.
+
+```bash
+CONFIG=config.yml uvicorn "txtai.api:app"
+```
+
+Uvicorn is a full-featured production-ready server. See the [Uvicorn deployment guide](https://www.uvicorn.org/deployment/) for more on configuration options.
+
+## Connect to API
+
+The default port for the API is 8000. See the uvicorn link above to change this.
+
+txtai has a number of language bindings which abstract the API (see links below). Alternatively, code can be written to connect directly to the API. Documentation for a live running instance can be found at the `/docs` url (i.e. http://localhost:8000/docs). The following example runs a workflow using cURL.
+
+```bash
+curl \
+  -X POST "http://localhost:8000/workflow" \
+  -H "Content-Type: application/json" \
+  -d '{"name":"sumfrench", "elements": ["https://github.com/neuml/txtai"]}'
+```
+
+## Local instance
+
+A local instance can be instantiated. In this case, a txtai application runs internally, without any network connections, providing the same consolidated functionality. This enables running txtai in Python with configuration.
+
+The configuration above can be run in Python with:
+
+```python
+from txtai import Application
+
+# Load and run workflow
+app = Application(config.yml)
+app.workflow("sumfrench", ["https://github.com/neuml/txtai"])
+```
+
+See this [link for a full list of methods](./methods).
+
+## Run with containers
+
+The API can be containerized and run. This will bring up an API instance without having to install Python, txtai or any dependencies on your machine!
+
+[See this section for more information](../cloud/#api).
+
+## Supported language bindings
+
+The following programming languages have bindings with the txtai API:
+
+- [Python](https://github.com/neuml/txtai.py)
+- [JavaScript](https://github.com/neuml/txtai.js)
+- [Java](https://github.com/neuml/txtai.java)
+- [Rust](https://github.com/neuml/txtai.rs)
+- [Go](https://github.com/neuml/txtai.go)
+
+The API also supports hosting [OpenAI-compatible](./openai) and [Model Context Protocol (MCP)](./mcp) endpoints.
+
+See the links below for detailed examples covering the API.
+
+| Notebook  | Description  |       |
+|:----------|:-------------|------:|
+| [API Gallery](https://github.com/neuml/txtai/blob/master/examples/08_API_Gallery.ipynb) | Using txtai in JavaScript, Java, Rust and Go | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/08_API_Gallery.ipynb) |
+| [Distributed embeddings cluster](https://github.com/neuml/txtai/blob/master/examples/15_Distributed_embeddings_cluster.ipynb) | Distribute an embeddings index across multiple data nodes | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/15_Distributed_embeddings_cluster.ipynb) |
+| [Embeddings in the Cloud](https://github.com/neuml/txtai/blob/master/examples/43_Embeddings_in_the_Cloud.ipynb) | Load and use an embeddings index from the Hugging Face Hub | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/43_Embeddings_in_the_Cloud.ipynb) |
+| [Custom API Endpoints](https://github.com/neuml/txtai/blob/master/examples/51_Custom_API_Endpoints.ipynb) | Extend the API with custom endpoints | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/51_Custom_API_Endpoints.ipynb) |
+| [API Authorization and Authentication](https://github.com/neuml/txtai/blob/master/examples/54_API_Authorization_and_Authentication.ipynb) | Add authorization, authentication and middleware dependencies to the API | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/54_API_Authorization_and_Authentication.ipynb) |
+| [OpenAI Compatible API](https://github.com/neuml/txtai/blob/master/examples/74_OpenAI_Compatible_API.ipynb) | Connect to txtai with a standard OpenAI client library | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/neuml/txtai/blob/master/examples/74_OpenAI_Compatible_API.ipynb) |