# HsienW > Open-source publisher. Listings imported from github.com/HsienW — credited to the original author with their license. - **Listings:** 24 - **Total installs:** 0 - **Profile:** https://agentstack.voostack.com/s/hsienw - **Website:** https://github.com/HsienW ## Published listings - [Bff Transport Boundary](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-bff-transport-boundary) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-bff-transport-boundary` Design and review Backend-for-Frontend transport boundaries. Use when implementing or changing request parsing, response mapping, streaming proxy behavior, CORS, header allowlists, authentication boundaries, timeouts, cancellation, error envelopes, or upstream orchestration. - [Node Engineering](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-node-engineering) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-node-engineering` Guide robust Node.js and TypeScript engineering. Use when working on Node services, scripts, CLIs, tests, streams, async workflows, module boundaries, environment configuration, logging, caching, profiling, or graceful shutdown. - [Distributed Step Lock](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-distributed-step-lock) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-distributed-step-lock` Design and review distributed locks for agent step transitions. Use when preventing concurrent workers, duplicate resumes, retries, compensation, or external requests from mutating the same task or step state at the same time. - [Retry Budget Policy](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-retry-budget-policy) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-retry-budget-policy` Design and review retry budgets for agent steps, tools, providers, and transport calls. Use when classifying retryable errors, enforcing max attempts, respecting Retry-After, applying backoff and jitter, handling timeouts, or preventing retries for permission, validation, business, or user-cancelled failures. - [Tool Renderer Contract](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-tool-renderer-contract) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-tool-renderer-contract` Design and review structured tool-result rendering. Use when rendering tool calls, tool messages, structured tool outputs, status cards, fallback JSON/text displays, parser boundaries, display status mappings, or unknown tool results. - [Frontend Ui Engineering](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-frontend-ui-engineering) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-frontend-ui-engineering` Build production-quality frontend interfaces. Use when creating or modifying UI components, layouts, interaction states, responsive behavior, accessibility, visual polish, or user-facing workflows. - [Observability And Instrumentation](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-observability-and-instrumentation) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-observability-and-instrumentation` Add or review observability. Use when adding logs, metrics, traces, audit events, health checks, alerts, or production diagnostics for features, background jobs, APIs, tools, and integrations. - [Compensation Saga Runtime](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-compensation-saga-runtime) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-compensation-saga-runtime` Design and review compensation and Saga runtime behavior for agent workflows. Use when handling multi-step side effects, rollback plans, irreversible actions, compensation ordering, manual escalation, cancellation cleanup, or audit-linked recovery flows. - [Frontend Streaming Contract](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-frontend-streaming-contract) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-frontend-streaming-contract` Design and review frontend streaming contracts. Use when handling server-sent events, WebSocket messages, async iterables, stream parsers, reducer state, terminal states, progress timelines, cancellation, retries, or UI updates driven by runtime events. - [Agent Task State Machine](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-agent-task-state-machine) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-agent-task-state-machine` Design and review generic agent task and step state machines. Use when adding business-level task progress, step lifecycle tracking, task events, persistence, streaming timelines, resumable task state, or cross-layer task status APIs. - [Langgraph Runtime Boundary Review](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-langgraph-runtime-boundary-review) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-langgraph-runtime-boundary-review` Review LangGraph native runtime boundaries before building custom agent runtime infrastructure. Use when deciding whether queueing, workers, checkpointers, stores, interrupts, resume flows, retries, task semantics, audit, locks, or cost tracking should be native runtime responsibilities or custom application runtime responsibilities. - [Code Review And Quality](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-code-review-and-quality) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-code-review-and-quality` Conduct multi-axis code review. Use before merging code written by an agent or human, when assessing diffs for correctness, maintainability, security, tests, observability, and contract risk. - [Langgraph Backend Contract](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-langgraph-backend-contract) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-langgraph-backend-contract` Design and review LangGraph backend contracts. Use when creating or changing graph state, nodes, edges, reducers, commands, sends, checkpoints, runtime events, provider adapters, tool adapters, prompts, terminal states, or resumable workflows. - [Type Boundary Contract](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-type-boundary-contract) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-type-boundary-contract` Design and review type contracts across package, service, frontend, backend, tool, event, and transport boundaries. Use when defining schemas, discriminated unions, runtime parsers, error envelopes, schemaVersion fields, or duplicated transport/domain types. - [Security And Hardening](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-security-and-hardening) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-security-and-hardening` Harden software against security risk. Use when handling user input, authentication, authorization, sessions, secrets, file uploads, external integrations, webhooks, browser data, storage, or privileged actions. - [Context Budget Governance](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-context-budget-governance) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-context-budget-governance` Design and review context budget governance for agent prompts and model calls. Use when assembling long conversation context, tool results, retrieved evidence, memory, task state, system rules, multimodal observations, or compressed summaries under a token budget. - [Test Driven Development](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-test-driven-development) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-test-driven-development` Drive implementation with tests. Use when fixing bugs, changing behavior, adding logic, modifying contracts, or proving that agent-written code works and remains safe across regressions. - [Idempotency Audit Contract](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-idempotency-audit-contract) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-idempotency-audit-contract` Design and review idempotency and audit contracts for agent runtimes. Use when preventing duplicate side effects, propagating idempotency keys, persisting operation history, redacting sensitive payloads, auditing tool decisions, or reconstructing task execution after retries and resumes. - [Performance Optimization](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-performance-optimization) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-performance-optimization` Optimize application performance with evidence. Use when latency, throughput, memory, bundle size, rendering speed, Core Web Vitals, query time, startup time, or resource usage matters. - [Incremental Implementation](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-incremental-implementation) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-incremental-implementation` Deliver changes in small verifiable increments. Use when implementing a multi-file feature, refactor, migration, bug fix, or any task that is large enough to become risky if completed in one pass. - [Api And Interface Design](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-api-and-interface-design) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-api-and-interface-design` Guide stable API and interface design. Use when creating or changing public module boundaries, REST or GraphQL endpoints, event contracts, SDK methods, data transfer objects, error envelopes, or cross-team interfaces. - [Debugging And Error Recovery](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-debugging-and-error-recovery) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-debugging-and-error-recovery` Guide systematic root-cause debugging. Use when tests fail, builds break, runtime behavior is unexpected, logs show errors, or repeated fixes are not resolving the same issue. - [Chat Gun React Agent](https://agentstack.voostack.com/l/mcp-hsienw-chat-gun-react-agent) — MCP server · Free · security-reviewed — `agentstack add mcp-hsienw-chat-gun-react-agent` 🤖A production-oriented full-stack Agent Chat system built with React, TypeScript, LangGraph JS, Qwen/OpenAI-compatible models, native tools, optional MCP, HITL, streaming events, multimodal input, and deep research workflows. - [Agent Observability Fault Tolerance](https://agentstack.voostack.com/l/skill-hsienw-ai-agent-engineering-playbook-agent-observability-fault-tolerance) — Skill · Free · security-reviewed — `agentstack add skill-hsienw-ai-agent-engineering-playbook-agent-observability-fault-tolerance` Design and review agent runtime observability and model/provider fault tolerance. Use when adding metrics, traces, cost tracking, audit alignment, structured runtime events, model fallback, structured output repair, refusal handling, provider timeouts, or local execution tree diagnostics. --- Seller on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Install any with `agentstack add `.