MCP-UI is a monorepo SDK implementing the MCP Apps standard for rendering interactive UIs over the Model Context Protocol. It provides server-side tools (in TypeScript, Python, and Ruby) to create UI resources, and a client-side React SDK to render them in sandboxed iframes. The architecture centers on a secure double-iframe proxy pattern that isolates third-party HTML and external URLs, with JSON-RPC communication via AppBridge. The codebase is well-structured with comprehensive tests, semantic release automation, and cloudflare workers example, demonstrating strong engineering practices across multiple languages.
Agentspan is a comprehensive, multi-language agent orchestration platform built on top of Orkes Conductor. It provides SDKs in Python, TypeScript, Java, and C# for defining, running, and deploying AI agents with rich features: tools, guardrails, multi-agent strategies (handoff, sequential, parallel, router, swarm, plan-execute), streaming, human-in-the-loop, code execution in sandboxes, credential management, and scheduling. The architecture follows a server/client pattern where agent definitions compile to Conductor workflows, with a Java/Spring Boot server, a Go CLI with a Bubble Tea TUI, and a React/Material-UI web interface for visual workflow editing and execution monitoring. The repository is archived (read-only) as of August 2026, with its active development having merged into the Orkes Conductor repository. Despite being archived, the codebase represents a mature, well-crafted multi-agent runtime with extensive examples, comprehensive testing, and clean abstractions across all supported languages. The SDKs demonstrate consistent design patterns—agent composition via strategies, tool registration via decorators/annotations, guardrail chains with composable termination conditions, and thread-safe credential injection—making the codebase a valuable reference for building agent orchestration systems.