Source: https://seerepo.com/r/ag-ui-protocol/ag-ui/built Markdown source: https://seerepo.com/r/ag-ui-protocol/ag-ui/built.md Description: ag-ui is a Python repo built with ASP.NET Core, FastAPI, Spring, activity-compose, AIOHTTP, and 8 more. # What is ag-ui built with? ag-ui is a Python repo built with ASP.NET Core, FastAPI, Spring, activity-compose, AIOHTTP, and 8 more. It uses AI through go, Microsoft.Extensions.AI.Abstractions, openai-agents, spring-ai-bom, spring-ai-client-chat, and 19 more, measures its use with PostHog, makes its content with coil-compose, streamdown, markdown-it, and yaml, validates its data with Pydantic, Zod, zod-to-json-schema, @cfworker/json-schema, and Ajv, is tested with io.ktor:ktor-client-mock, junit-bom, org.jetbrains.kotlinx:kotlinx-coroutines-test, reactor-test, org.junit.jupiter:junit-jupiter, and 4 more, deploys with io.ktor:ktor-client-logging, slf4j-simple, github.com/sirupsen/logrus, and log, and uses @mastra/libsql and MCP. It has 879,462 written lines, with 1,756 test files. Read on November 7, 2026, at commit 37b4da9. Repository: https://github.com/ag-ui-protocol/ag-ui ## Backend (/) ### The base - **[ASP.NET Core](https://seerepo.com/uses/aspnet-core)** - **[FastAPI](https://seerepo.com/uses/fastapi)**: 13 files - **[Spring](https://seerepo.com/uses/spring)**: 2 files ### AI - **go** - **Microsoft.Extensions.AI.Abstractions** - **openai-agents** - **spring-ai-bom** - **spring-ai-client-chat** - **strands-agents** - **Microsoft.Extensions.AI**: 17 files - **google-adk**: 10 files - **ag-ui-a2ui-toolkit**: 7 files - **CrewAI**: 7 files - **google-antigravity**: 6 files - **[LangChain](https://seerepo.com/uses/langchain)**: 5 files - **[LangGraph](https://seerepo.com/uses/langgraph)**: 4 files - **[litellm](https://seerepo.com/uses/litellm)**: 4 files - **langroid**: 1 file - **[mcp](https://seerepo.com/uses/mcp)**: 1 file ## Support (/) ### The base - **activity-compose** - **[AIOHTTP](https://seerepo.com/uses/aiohttp)** - **[core-ktx](https://seerepo.com/uses/core-ktx)** - **java-server** - **[Tokio](https://seerepo.com/uses/tokio)**: 1 file - **[uvicorn](https://seerepo.com/uses/uvicorn)**: 1 file ### Content - **[coil-compose](https://seerepo.com/uses/coil-compose)** ### Validation - **[Pydantic](https://seerepo.com/uses/pydantic)**: 10 files ### Testing - **io.ktor:ktor-client-mock** - **junit-bom** - **org.jetbrains.kotlinx:kotlinx-coroutines-test** - **reactor-test** - **org.junit.jupiter:junit-jupiter**: 30 files - **github.com/stretchr/testify**: 13 files - **org.springframework.boot:spring-boot-starter-test**: 1 file - **Vitest**: 1 file ### Deploy - **io.ktor:ktor-client-logging** - **[slf4j-simple](https://seerepo.com/uses/slf4j-simple)** - **[github.com/sirupsen/logrus](https://seerepo.com/uses/githubcom-sirupsen-logrus)**: 2 files - **[log](https://seerepo.com/uses/log)**: 2 files ### Tools - **Grpc.Tools** - **sorbet-runtime**: 7 files ### Other - **ag-ui-protocol** - **asyncio** - **coil-network-ktor3** - **io.ktor:ktor-client-content-negotiation** - **[JetBrains](https://seerepo.com/uses/jetbrains)** - **kotlinx-serialization-json** - **reactor-core** - **s** - **System.Text.Json**: 59 files - **co.touchlab:kermit**: 13 files - **serde_json**: 10 files - **serde**: 8 files - **com.fasterxml.jackson.core:jackson-databind**: 6 files - **Ktor**: 6 files - **io.ktor:ktor-serialization-kotlinx-json**: 5 files - **async-trait**: 4 files - **futures**: 4 files - **reqwest**: 3 files - **thiserror**: 3 files - **[Google](https://seerepo.com/uses/google)**: 2 files - **Google.Protobuf**: 2 files - **http**: 2 files - **json**: 2 files - **sse-starlette**: 2 files - **bytes**: 1 file - **httpx**: 1 file - **json-patch**: 1 file - **json-repair**: 1 file - **meta**: 1 file - **System.Net.ServerSentEvents**: 1 file - **uuid**: 1 file ## Frontend (apps/dojo) ### The base - **[React](https://seerepo.com/uses/react)**: 60 files · [in apps/dojo/package.json](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/package.json) - **[Next.js](https://seerepo.com/uses/nextjs)**: 11 files · [in apps/dojo/package.json](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/package.json) ### Styles - **[Tailwind CSS](https://seerepo.com/uses/tailwind-css)** - **[next-themes](https://seerepo.com/uses/next-themes)**: 8 files - **[class-variance-authority](https://seerepo.com/uses/class-variance-authority)**: 2 files - **[tailwind-merge](https://seerepo.com/uses/tailwind-merge)**: 1 file ### Interface - **[Radix UI](https://seerepo.com/uses/radix-ui)**: 4 files - **@a2ui/web_core**: 1 file - **@copilotkit/react-ui**: 1 file - **[@monaco-editor/react](https://seerepo.com/uses/monaco-editor-react)**: 1 file - **[embla-carousel-react](https://seerepo.com/uses/embla-carousel-react)**: 1 file - **[tiptap](https://seerepo.com/uses/tiptap)**: 1 file ### Icons - **[Lucide](https://seerepo.com/uses/lucide)**: 10 files - **[@phosphor-icons/react](https://seerepo.com/uses/phosphor-icons-react)**: 1 file ## Backend (apps/dojo) ### The base - **[Express](https://seerepo.com/uses/express)**: [in apps/dojo/package.json](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/package.json) - **[Hono](https://seerepo.com/uses/hono)**: 3 files ### Data - **@mastra/libsql**: 1 file ### AI - **copilotkit**: 37 files - **mastra**: 15 files - **@a2a-js/sdk**: 1 file - **[@langchain/openai](https://seerepo.com/uses/langchain-openai)**: 1 file ### Services - **[PostHog](https://seerepo.com/uses/posthog)**: 6 files · [apps/dojo/instrumentation-client.ts, line 1](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/instrumentation-client.ts#L1) ## Support (apps/dojo) ### Content - **[streamdown](https://seerepo.com/uses/streamdown)**: 2 files - **[markdown-it](https://seerepo.com/uses/markdown-it)**: 1 file ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 21 files - **[zod-to-json-schema](https://seerepo.com/uses/zod-to-json-schema)**: 1 file ### Tools - **concurrently**: 2 files ### Other - **clsx**: 1 file - **dedent**: 1 file - **diff**: 1 file - **rxjs**: 1 file ## Backend (integrations/a2a/typescript) ### AI - **@a2a-js/sdk**: 3 files ## Support (integrations/a2a/typescript) ### Other - **rxjs**: 1 file ## Support (integrations/adk-middleware/js) ### Validation - **@cfworker/json-schema**: 1 file ### Testing - **Vitest**: 17 files ### Other - **rxjs**: 1 file ## Support (integrations/adk-middleware/typescript) ### Testing - **Vitest**: 1 file ## Support (integrations/agno/typescript) ### Testing - **Vitest**: 1 file ## Support (integrations/antigravity/typescript) ### Testing - **Vitest**: 1 file ## Backend (integrations/aws-strands/typescript) ### The base - **[Express](https://seerepo.com/uses/express)**: 2 files · [in apps/dojo/package.json](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/package.json) ### AI - **@strands-agents/sdk**: 8 files ## Support (integrations/aws-strands/typescript) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 8 files ### Testing - **Vitest**: 89 files ### Other - **cors**: 1 file - **http**: 1 file - **rxjs**: 1 file ## Backend (integrations/claude-agent-sdk/typescript) ### Services - **MCP**: 1 file · [integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts, line 3](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts#L3) ## Support (integrations/claude-agent-sdk/typescript) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 1 file ### Testing - **Vitest**: 11 files ### Other - **rxjs**: 2 files ## Support (integrations/claude-managed-agents/typescript) ### Testing - **Vitest**: 17 files ### Other - **rxjs**: 1 file ## Backend (integrations/community/cloudflare-agents/typescript) ### AI - **[ai](https://seerepo.com/uses/ai)**: 1 file ## Support (integrations/community/cloudflare-agents/typescript) ### Testing - **Vitest**: 3 files ### Other - **rxjs**: 2 files ## Backend (integrations/community/omnara/typescript) ### AI - **@omnara/sdk**: 1 file ## Support (integrations/community/omnara/typescript) ### Content - **[yaml](https://seerepo.com/uses/yaml)**: 1 file ### Testing - **Vitest**: 2 files ### Other - **rxjs**: 1 file ## Support (integrations/community/spring-ai/typescript) ### Testing - **Vitest**: 1 file ## Support (integrations/crew-ai/typescript) ### Testing - **Vitest**: 1 file ## Backend (integrations/langchain/typescript) ### AI - **[LangChain](https://seerepo.com/uses/langchain)**: 4 files ## Support (integrations/langchain/typescript) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 1 file ### Testing - **Vitest**: 7 files ### Other - **rxjs**: 1 file ## Backend (integrations/langgraph/typescript) ### AI - **[LangChain](https://seerepo.com/uses/langchain)**: 7 files ## Support (integrations/langgraph/typescript) ### Testing - **Vitest**: 28 files ### Other - **rxjs**: 1 file ## Support (integrations/llama-index/typescript) ### Testing - **Vitest**: 1 file ### Other - **rxjs**: 1 file ## Backend (integrations/mastra/typescript) ### AI - **mastra**: 4 files - **@copilotkit/runtime**: 1 file ## Support (integrations/mastra/typescript) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 1 file ### Testing - **Vitest**: 33 files ### Other - **fast-json-patch**: 1 file - **rxjs**: 1 file ## Support (integrations/openai-agents/typescript) ### Testing - **Vitest**: 1 file ## Backend (integrations/vercel-ai-sdk/typescript) ### AI - **[ai](https://seerepo.com/uses/ai)**: 1 file ## Support (integrations/vercel-ai-sdk/typescript) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 1 file ### Testing - **Vitest**: 2 files ### Other - **rxjs**: 1 file ## Support (integrations/watsonx/typescript) ### Testing - **Vitest**: 7 files ### Other - **rxjs**: 2 files ## Backend (middlewares/a2a-middleware) ### AI - **@a2a-js/sdk**: 2 files ## Support (middlewares/a2a-middleware) ### Testing - **Vitest**: 1 file ### Other - **rxjs**: 1 file ## Support (middlewares/a2ui-middleware) ### Testing - **Vitest**: 7 files ### Other - **clarinet**: 1 file - **rxjs**: 1 file ## Support (middlewares/event-throttle-middleware) ### Testing - **Vitest**: 1 file ### Other - **rxjs**: 1 file ## Backend (middlewares/mcp-apps-middleware) ### Services - **MCP**: 1 file · [integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts, line 3](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts#L3) ## Support (middlewares/mcp-apps-middleware) ### Testing - **Vitest**: 5 files ### Other - **rxjs**: 1 file ## Backend (middlewares/mcp-middleware) ### Services - **MCP**: 1 file · [integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts, line 3](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/integrations/claude-agent-sdk/typescript/src/loopback-mcp.ts#L3) ## Support (middlewares/mcp-middleware) ### Testing - **Vitest**: 1 file ### Other - **rxjs**: 1 file ## Support (middlewares/middleware-starter) ### Other - **rxjs**: 1 file ## Support (sdks/typescript/packages/a2ui-toolkit) ### Testing - **Vitest**: 3 files ## Support (sdks/typescript/packages/cli) ### Testing - **Vitest**: 4 files ### Tools - **commander**: 1 file - **giget**: 1 file - **Inquirer**: 1 file ## Support (sdks/typescript/packages/client) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 2 files ### Testing - **Vitest**: 59 files - **@copilotkit/aimock**: 1 file ### Other - **rxjs**: 17 files - **fast-json-patch**: 3 files - **untruncate-json**: 2 files - **uuid**: 2 files - **compare-versions**: 1 file ## Support (sdks/typescript/packages/core) ### Validation - **[Zod](https://seerepo.com/uses/zod)**: 1 file ### Testing - **Vitest**: 15 files ### Tools - **esbuild**: 1 file ## Support (sdks/typescript/packages/proto) ### Testing - **Vitest**: 14 files ### Other - **@bufbuild/protobuf**: 1 file ## Support (spec) ### Validation - **[Ajv](https://seerepo.com/uses/ajv)**: 1 file ### Testing - **Vitest**: 9 files ### Tools - **Prettier**: 1 file ## Other repos with a similar stack - [vectorize-io/hindsight](https://seerepo.com/r/vectorize-io/hindsight/built): FastAPI, AIOHTTP, Tokio, uvicorn, React, Next.js, MCP, openai-agents, strands-agents, google-adk, CrewAI, LangChain, litellm, Pydantic, Tailwind CSS, next-themes, class-variance-authority, tailwind-merge, Radix UI, Lucide, Zod, ai · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/vectorize-io/hindsight) - [Significant-Gravitas/AutoGPT](https://seerepo.com/r/Significant-Gravitas/AutoGPT/built): FastAPI, AIOHTTP, uvicorn, React, Next.js, PostHog, Pydantic, Tailwind CSS, next-themes, class-variance-authority, tailwind-merge, Radix UI, embla-carousel-react, streamdown, Zod, ai · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/Significant-Gravitas/AutoGPT) - [bytedance/deer-flow](https://seerepo.com/r/bytedance/deer-flow/built): FastAPI, uvicorn, React, Next.js, LangChain, LangGraph, Tailwind CSS, next-themes, class-variance-authority, tailwind-merge, Radix UI, embla-carousel-react, Lucide, streamdown, Zod, ai · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/bytedance/deer-flow) - [bojieli/ai-agent-book](https://seerepo.com/r/bojieli/ai-agent-book/built): FastAPI, AIOHTTP, uvicorn, React, Next.js, Express, PostHog, MCP, litellm, Pydantic, Tailwind CSS, class-variance-authority, tailwind-merge, Radix UI, Lucide · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/bojieli/ai-agent-book) - [ruvnet/ruflo](https://seerepo.com/r/ruvnet/ruflo/built): Tokio, React, Express, MCP, Tailwind CSS, next-themes, class-variance-authority, tailwind-merge, Radix UI, embla-carousel-react, Lucide, Zod, yaml, Ajv · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/ruvnet/ruflo) - [cline/cline](https://seerepo.com/r/cline/cline/built): React, PostHog, MCP, Tailwind CSS, next-themes, class-variance-authority, tailwind-merge, Radix UI, embla-carousel-react, Lucide, streamdown, Zod, ai, yaml · [Compare](https://seerepo.com/compare/ag-ui-protocol/ag-ui/vs/cline/cline) ## Frequently asked questions ### What language is ag-ui written in? ag-ui is written in Python, with 879,462 written lines. ### What framework does ag-ui use? ag-ui is built with ASP.NET Core, FastAPI, Spring, activity-compose, AIOHTTP, core-ktx, java-server, Tokio, uvicorn, React, Next.js, Express, and Hono. ### Does ag-ui use AI? Yes. ag-ui uses AI through go, Microsoft.Extensions.AI.Abstractions, openai-agents, spring-ai-bom, spring-ai-client-chat, strands-agents, Microsoft.Extensions.AI, google-adk, ag-ui-a2ui-toolkit, CrewAI, google-antigravity, LangChain, LangGraph, litellm, langroid, mcp, copilotkit, mastra, @a2a-js/sdk, @langchain/openai, @strands-agents/sdk, ai, @omnara/sdk, and @copilotkit/runtime. ### What services does ag-ui use? ag-ui measures its use with PostHog and uses @mastra/libsql and MCP. The proof: [apps/dojo/instrumentation-client.ts, line 1](https://github.com/ag-ui-protocol/ag-ui/blob/37b4da90c8dfba2b7ef2182c738fda5350f0fc60/apps/dojo/instrumentation-client.ts#L1) ### Does ag-ui have tests? Yes. ag-ui has 1,756 test files and is tested with io.ktor:ktor-client-mock, junit-bom, org.jetbrains.kotlinx:kotlinx-coroutines-test, reactor-test, org.junit.jupiter:junit-jupiter, github.com/stretchr/testify, org.springframework.boot:spring-boot-starter-test, Vitest, and @copilotkit/aimock. ### Which repos have a stack like ag-ui's? The ones that share most of its stack: vectorize-io/hindsight, Significant-Gravitas/AutoGPT, and bytedance/deer-flow. ## What is your repo built with? Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.