# Cristhianzl > Open-source publisher. Listings imported from github.com/Cristhianzl — credited to the original author with their license. - **Listings:** 19 - **Total installs:** 0 - **Profile:** https://agentstack.voostack.com/s/cristhianzl - **Website:** https://github.com/Cristhianzl ## Published listings - [Building Langflow Components](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-building-langflow-components) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-building-langflow-components` Create, evolve, and ship Langflow Components — the building blocks of every flow. Use when the user asks to "create a component", "add a provider component", "build an LLM component", "add Anthropic / OpenAI / Chroma / etc. integration", "expose this as a Component", or "wrap this LangChain class as a Component". Enforces the immutable-class-name rule, the inputs/outputs API, the hot-reload workf… - [Api Design](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-api-design) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-api-design` Design and review HTTP/REST (and choose between REST/GraphQL/gRPC) APIs that are contract-first, resource-oriented, backward-compatible, and secure by default. Use whenever the task touches an API surface — designing an API, adding or changing an endpoint or route, picking an HTTP method or status code, naming resources, paginating a list, versioning, deprecating a field, modeling errors, idempot… - [Writing Pull Requests](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-writing-pull-requests) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-writing-pull-requests` Generate Langflow-shaped PR titles, commit messages, and descriptions from staged changes or a branch diff — conventional-commit format with Langflow scopes (auth, components, graph, api, frontend, bundles/, lfx, docs, ci), Fixes #N allowed in description, no Co-Authored-By trailer, version bumps via make patch v=X.Y.Z, BUNDLE_API.md callout when bundles change, breaking-change ! flag when… - [Exploratory Testing](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-exploratory-testing) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-exploratory-testing` Run structured exploratory testing — write a charter, time-box a session, apply heuristics and oracles to discover bugs the scripted suite never looks for, then debrief and file solid bug reports. Use when the user says "test this manually", "find bugs", "explore the feature", "edge cases", "risk-based testing", "session-based", or asks for a charter, a test session, or a bug hunt on a flow that… - [Reviewing Code](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-reviewing-code) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-reviewing-code` Review a Langflow pull request and produce a GitHub-comment-shaped review with severity-labeled findings (B/I/R/N) plus a copy-paste-safe action checklist — applying Langflow blockers (Component class rename = breaking, Alembic Phase label required, BUNDLE_API.md changelog gate, no-mock policy, SecretStrInput for API keys, no top-level SDK instantiation in components). Use when the user asks to r… - [Writing Prd](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-writing-prd) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-writing-prd` Author product requirements — PRDs, product specs, one-pagers, PR-FAQs, product briefs — that lead with the problem, define testable success metrics and acceptance criteria, and make non-goals explicit. Use when the user asks to write a PRD, write/define product requirements, write a product spec, write a one-pager, write a PR-FAQ, "write a spec", "define requirements", scope a feature, or draft… - [Evaluating Ai Output](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-evaluating-ai-output) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-evaluating-ai-output` Evaluate non-deterministic LLM/AI output with evals instead of one-shot "it worked" — define expected behavior first, measure pass@k / pass^k, and grade with code / model / human graders. Use when building or changing an AI/LLM feature, an agent, a prompt, a RAG pipeline, or a classifier, where a single good run is not proof of correctness. Complements writing-tests (deterministic logic) and deve… - [Fixing Bugs](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-fixing-bugs) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-fixing-bugs` Fix a Langflow bug using strict TDD — UNDERSTAND → REPRODUCE (RED) → VERIFY RED → FIX → VERIFY GREEN → VALIDATE → REFACTOR — with Langflow hotspot awareness (lfx vs langflow-base split, dynamic component discovery, expand-contract Alembic migrations, pre-commit must invoke uv run git commit). Use when the user reports a bug in Langflow, mentions Sentry/error/regression, pastes a stack trace, or a… - [Playwright Cli](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-playwright-cli) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-playwright-cli` Automate browser interactions, test web pages and work with Playwright tests. - [Building Frontend Ui](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-building-frontend-ui) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-building-frontend-ui` Build, refactor, and review frontend UI in any framework — components, accessibility, forms, client state and data fetching, responsive layout, performance, and client-side security/PII. Use whenever the task touches the UI layer: creating or changing a component, page, or screen; styling or theming; accessibility/a11y; forms; client state; responsive/mobile layout; or reviewing/refactoring front… - [Security Review](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-security-review) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-security-review` Review an application's code for security across frontend AND backend and produce a prioritized, safe-to-apply remediation plan — OWASP Top 10 (2025), OWASP API Top 10, plus privacy (LGPD/GDPR). Use when the user asks for a "security review", "security audit", "harden this", "is this secure?", "check for vulnerabilities", "OWASP", "pentest-style review", or wants a focused security pass on a feat… - [Running Agent Loops](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-running-agent-loops) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-running-agent-loops` Run a multi-step or unattended agent loop safely — sequential pipelines, implement→review→fix (PR) loops, parallel fan-out, and RFC→DAG orchestration. Use when the user wants to "loop", "run autonomously", "iterate until it's done", chain `claude -p` calls, fan out parallel agents on a spec, or set up an implement→verify→commit cycle. Covers the cross-iteration context bridge and the de-sloppify… - [Ensuring Cross Platform](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-ensuring-cross-platform) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-ensuring-cross-platform` Apply platform-agnostic engineering rules so Langflow code, tests, and Docker images behave identically on Ubuntu, macOS (Intel x86_64 + Apple Silicon arm64), and native Windows — plus the linux/amd64 + linux/arm64 Docker matrix and the separate Langflow Desktop distribution for Windows and macOS. Use when writing or reviewing code that touches the filesystem, shell, subprocess, encoding, time, p… - [Developing Features](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-developing-features) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-developing-features` Write production code in Langflow with security-first thinking, SOLID design, pragmatic principles, observability, and strict file-structure limits — tuned for Langflow conventions (uv workspaces, SQLModel, lfx vs langflow-base split, pre-commit invoked via uv run). Use when implementing a new feature, designing a service, refactoring backend code, adding an API route, or whenever the task is "bu… - [Writing Tests](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-writing-tests) — Skill · Free — `agentstack add skill-cristhianzl-claude-skills-czl-writing-tests` Write unit, integration, and E2E tests in Langflow that follow the pyramid, AAA structure, should_X_when_Y naming, the 75% (target 80%) branch coverage gate per supported OS, AND Langflow's specific conventions (prefer real integrations over mocks per AGENTS.md, ComponentTestBase[With/Without]Client fixtures, uv run pytest, sub-package dev sync, marks like api_key_required and no_blockbuster). Us… - [Developing Features Tdd](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-developing-features-tdd) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-developing-features-tdd` Build a Langflow feature with strict TDD — UNDERSTAND → DESIGN → RED → VERIFY RED → GREEN → VERIFY GREEN → REFACTOR → VALIDATE → REPEAT — applying Langflow's prefer-real-integrations-over-mocks policy, ComponentTestBase fixtures, and the graph test pattern from AGENTS.md. Use when building a new feature with TDD, when the user says "TDD this", "tests first", "red green refactor", or asks for feat… - [Threat Modeling](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-threat-modeling) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-threat-modeling` Structured security design analysis — find what can go wrong before an attacker does. Build a Data Flow Diagram with trust boundaries, apply STRIDE per element, add abuse/misuse cases, and map every threat to a control and a test. Use when the user asks to threat model a feature/system, run STRIDE, map the attack surface, do a security design review, write abuse cases, identify trust boundaries,… - [Documenting Features](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-documenting-features) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-documenting-features` Produce Langflow feature documentation — engineering-side as a 10-section single Markdown file (overview, ubiquitous language, domain model, Gherkin behaviors, ADRs, technical spec, observability, deployment, C4 diagrams, platform compatibility) AND user-facing pages in the Docusaurus site at docs/docs/ (Concepts, Components, Bundles, Contributing). Use when the user asks to document a Langflow f… - [Debugging Agent Runs](https://agentstack.voostack.com/l/skill-cristhianzl-claude-skills-czl-debugging-agent-runs) — Skill · Free · security-reviewed — `agentstack add skill-cristhianzl-claude-skills-czl-debugging-agent-runs` Recover when the AGENT itself is stuck — looping, repeating the same failed action, burning tokens/budget, overflowing context, drifting from the goal, or acting on stale state. Use when a run isn't converging and reworded retries aren't helping. This is a workflow you follow, not a hidden runtime that auto-heals. For bugs in the product code use fixing-bugs. --- Seller on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Install any with `agentstack add `.