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+# ADR 003: JAN PLUGINS
+
+## Changelog
+
+- Oct 5th 2023: Initial draft
+
+## Status
+
+Accepted
+
+## Context
+
+Modular Architecture w/ Plugins:
+
+- Jan will have an architecture similar to VSCode or k8Lens
+- "Desktop Application" whose functionality can be extended thru plugins
+- Jan's architecture will need to accomodate plugins for (a) Persistence(b) IAM(c) Teams and RBAC(d) Policy engines(e) "Apps" (i.e. higher-order business logic)(f) Themes (UI)
+- Nitro's architecture will need to accomodate plugins for different "model backends"(a) llama.cpp(b) rkwk (and others)(c) 3rd-party AIs
+
+## Decision
+
+![Architecture](./images/adr-003-01.png)
+
+## Consequences
+
+What becomes easier or more difficult to do because of this change?
+
+## Reference
+[Plugin APIs](./adr-003-jan-plugins.md)
diff --git a/adr/docs/adr-003-plugins.md b/adr/docs/adr-003-plugins.md
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+## JAN service & plugin APIs
+
+Jan frontend components will communicate with plugin functions via Service Interfaces:
+
+
+All of the available APIs are listed in [CoreService](../../web/shared/coreService.ts)
+
+- Data Service:
+    - GET_CONVERSATIONS: retrieve all of the conversations
+    - CREATE_CONVERSATION: start a new conversation
+    - DELETE_CONVERSATION: delete an existing conversation
+    - GET_CONVERSATION_MESSAGES: retrieve a certain conversation messages
+    - CREATE_MESSAGE: store a new message (both sent & received) 
+    - UPDATE_MESSAGE: update an existing message (streaming)
+    - STORE_MODEL: store new model information (when clicking download)
+    - UPDATE_FINISHED_DOWNLOAD: mark a model as downloaded
+    - GET_UNFINISHED_DOWNLOAD_MODELS: retrieve all unfinished downloading model (TBD)
+    - GET_FINISHED_DOWNLOAD_MODELS: retrieve all finished downloading model (TBD)
+    - DELETE_DOWNLOAD_MODEL: delete a model (TBD)
+    - GET_MODEL_BY_ID: retrieve model information by its ID
+
+- Inference Service:
+    - INFERENCE_URL: retrieve inference endpoint served by plugin
+    - INIT_MODEL: runs a model
+    - STOP_MODEL: stop a running model
+
+- Model Management Service: (TBD)
+    - GET_AVAILABLE_MODELS: retrieve available models (deprecate soon)
+    - GET_DOWNLOADED_MODELS: (deprecated)
+    - DELETE_MODEL: (deprecated)
+    - DOWNLOAD_MODEL: start to download a model
+    - SEARCH_MODELS: explore models with search query on HuggingFace (TBD)
+
+- Monitoring service:
+    - GET_RESOURCES_INFORMATION: retrieve total & used memory information
+    - GET_CURRENT_LOAD_INFORMATION: retrieve CPU load information
+
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