AI Agents & Systems — AI Agents, Skills & Tools
Agents, skills, guides, tools, and commands for ai agents & systems — 79 curated resources for building with AI coding agents.
Agent Tool Integration Engineer
Use this agent to wire tools and function-calling into an agent loop reliably — clean tool schemas, errors fed back as observations, retries with limits, idempotency, and parallel calls. Examples — "connect our APIs as agent tools", "our agent calls tools wrong / ignores tool errors", "add function-calling with proper error recovery to our agent".
Browser Agent Engineer
Use this agent to build, harden, or debug browser-automation agents — web tasks via Browser Use, Stagehand, Skyvern, or Playwright-based stacks. Examples: automate a portal workflow, make a flaky browser agent reliable, add verification and guardrails to web automation, choose between vision and DOM grounding.
Agent Reliability Reviewer
Use this agent to make an AI agent production-ready — reviewing its loops, cost controls, error handling, tool use, human-in-the-loop gates, checkpointing, and observability, then reporting concrete failure modes and fixes. Examples — "is our agent safe to ship?", "our agent loops forever / burns tokens, harden it", "add guardrails and recovery before we put this agent in front of users".
Context Engineer
Use this agent to engineer what an LLM agent carries in its context window — deciding what to include vs exclude vs retrieve on demand, designing project/agent memory (CLAUDE.md), compacting growing history, and allocating the token budget across system prompt, memory, retrieved docs, tool results, and conversation. Examples — "my agent forgets the schema we agreed on three turns ago", "the agent gets dumber and more inconsistent as the chat grows", "we're burning 60k tokens of tool output every turn", "what should this support agent always know vs look up?".
Eval Driven Developer
Use this agent to drive AI feature development with evals the way TDD drives code with tests — define success criteria and a representative eval set BEFORE iterating on prompts/models, then optimize against measured scores instead of vibes. Examples — "make the summarizer better" (turn it into measurable criteria first), "our prompt change keeps regressing quality, set up a loop that catches it", "add an eval gate to CI so a model swap can't silently degrade output", "we tweak prompts and pray — give us a baseline and a change-by-change scoreboard".
Tool Definition Generator
Generate clean function/tool schemas for an LLM agent from existing code or a spec — accurate JSON Schema, model-facing descriptions, honest required fields, and enums that make invalid calls impossible. Use when wiring functions into an agent's tool-calling loop.
Agent Trajectory Evaluator
Evaluate a multi-step AI agent's whole run — tool calls, intermediate steps, and final result — not just final-answer correctness, so you can pinpoint WHERE it went wrong. Use when building or debugging a tool-using or multi-step agent, when final-answer-only evals can't explain failures, or when a prompt/model change quietly makes the agent less efficient or more error-prone even though the answer still looks right.
Web Research Pipeline
Run a structured web-research pass on a question: plan the searches, find sources via search APIs, fetch and read the best ones, cross-check claims, and synthesize a cited answer — with source quality and disagreements surfaced honestly. Use for 'research X and tell me what's actually true' tasks that need more than one search and less than a day.
Agent Memory Designer
Design a project's CLAUDE.md and memory hierarchy by exploring the repo to learn its real build/test/lint commands, architecture, and non-obvious gotchas, then writing a concise, skimmable memory that keeps only what belongs in context. Use when onboarding a repo to Claude Code with no CLAUDE.md, or when an existing one is bloated, stale, or being ignored.
Human In The Loop Gate
Add a human approval checkpoint to an agent so it pauses before a risky or irreversible action (spending money, deleting data, sending messages, merging code) and resumes only after a human approves. Use when an agent acts autonomously on consequential operations.
Sandboxing AI-Generated Code: E2B vs Modal vs Daytona vs Vercel Sandbox
Where should agent-written code run? E2B vs Modal vs Daytona vs Vercel Sandbox compared on isolation, persistence, and cost, plus rules for safe execution.
Aider vs Claude Code: Open-Source vs Anthropic's Agent (2026)
Aider vs Claude Code — model-agnostic open-source pair-programmer vs Anthropic's tuned terminal harness. Which terminal coding agent fits your stack.
Browser Agents in 2026: Browser Use vs Stagehand vs Skyvern vs Playwright MCP
Four ways to give AI a browser — Browser Use, Stagehand, Skyvern, and Playwright MCP compared honestly on control, cost, and reliability for 2026.
Claude Code vs Gemini CLI: Which Terminal Agent (2026)
Claude Code vs Gemini CLI: first-party stability and a deep programmable harness vs open-source TypeScript, a big free tier, and the Antigravity cutover.
Claude Skills vs Custom GPTs: Different Answers to Reuse
Claude Skills are portable procedures; Custom GPTs are packaged chatbots inside ChatGPT. How they differ on portability, API access, sharing, and where each wins.
LangChain vs LlamaIndex in 2026: Agents or Data?
The classic framework confusion resolved — LangChain's agent loop and ecosystem vs LlamaIndex's data-and-documents depth — and when you'd genuinely use both.
LangGraph vs CrewAI: Agent Frameworks Compared (2026)
LangGraph vs CrewAI — explicit state-machine control vs role-based crew abstractions. Which agent framework fits your reliability bar and team.
Mem0 vs Zep vs Letta: Agent Memory Compared (2026)
Three philosophies of agent memory — Mem0's drop-in layer, Zep's temporal knowledge graphs, Letta's self-managing agents — and which fits your architecture.
n8n vs Dify: Which AI Workflow Platform? (2026)
Automation-first vs AI-native: n8n's 400+ integrations and agent nodes vs Dify's LLM-app platform with built-in RAG. Licenses, pricing, and the fit test.
OpenAI Agents SDK vs LangGraph: Minimal vs Controllable (2026)
OpenAI Agents SDK's three-primitive minimalism vs LangGraph's explicit graph and durable state — which agent framework matches your reliability bar in 2026.
Which Agent Framework in 2026? LangGraph vs CrewAI vs AutoGen vs OpenAI Agents SDK vs Claude Agent SDK
A decision guide to the major AI agent frameworks — control vs. abstraction, multi-agent models, state and durability, and which fits your project.
Agent Memory Architecture: Short-Term, Long-Term, and When to Use Each
How AI agents remember — working memory vs. persistent long-term memory, what to store, how to retrieve it, and how to keep context small.
Agentic RAG: When Retrieval Needs an Agent in the Loop
What agentic RAG is — retrieval as a tool an agent uses iteratively, with query planning, self-correction, and multi-source routing — and when the upgrade pays.
AI Coding Statistics 2026: The Numbers That Are Actually Sourced
How much code AI writes, who uses the tools, and what it does to quality — every statistic dated and traced to its primary source, updated on a cadence.
How Computer-Use Agents Work
Inside the perception-action loop that lets AI operate real software — screenshots in, clicks out — plus grounding, reliability, and when to use APIs instead.
Production Tool & Function Calling: Feed Errors Back as Observations
How agents use tools — the call/observe/retry loop, why errors must return to the model, and the schemas, idempotency, and limits that keep it reliable.
Getting Web Data into AI Agents: Search & Scraping APIs Compared
The agent web-data layer — Exa for semantic search, Firecrawl for extraction at scale, Tavily for all-in-one, Jina Reader for zero-setup — and how they compose.
The AI Engineer Roadmap for 2026
A staged path from API calls to production agents — the skills that matter in 2026, what to skip, and the guides and tools for each stage, in order.
The Agent Skills Standard: One SKILL.md for Every AI Tool
Agent Skills became an open standard in December 2025. Which tools read SKILL.md today — Copilot, Cursor, VS Code, Gemini CLI, Codex — and how to write portable skills.
Claude Skills on claude.ai and the API
How Agent Skills work beyond Claude Code: uploading to claude.ai, the /v1/skills API with code execution, Managed Agents, and the Agent SDK.
What Are Claude Skills? The Complete Guide
Claude Skills explained: what a SKILL.md is, how progressive disclosure keeps skills cheap, where they run, and how to install or write your own.
Why Your Agent Loops: Debugging AI Agents
The recurring agent failure modes — loops, premature victory, tool misuse, context poisoning, scope creep — diagnosed by their signatures, with fixes.
Realtime Voice Agents: Build on LiveKit, Buy Vapi, or Pipeline with Pipecat
The three ways to ship a realtime voice agent in 2026 — open infrastructure, managed platform, or OSS pipeline — and how speech-to-speech models fit in.
Human-in-the-Loop AI Workflows: Approval Gates That Keep Agents Safe and Trusted
How to design human-in-the-loop into agent workflows — when to require approval, gate patterns, confidence escalation, review UX, and feedback loops.
AgentOps
Observability for AI agents — session replay, cost and latency tracking, and debugging for multi-step runs.
Agno
A Python framework for building multi-agent systems with memory, knowledge, and tools — formerly Phidata, now with the AgentOS runtime.
Augment Code
AI coding assistant built for large, real-world codebases — a Context Engine that indexes the whole repo, with agents, chat, and completions in IDEs and a CLI.
AutoGen (AG2)
A multi-agent conversation framework where agents collaborate via message-passing, with group chat and code execution.
Browser Use
The most-adopted open-source browser-agent framework — point an LLM at a task and it drives a real browser: navigating, clicking, typing, extracting.
Browserbase
Managed headless-browser infrastructure for AI agents and web automation — serverless cloud browsers with stealth, proxies, live view, and Playwright/Stagehand.
CrewAI
A Python framework for orchestrating role-playing AI agents as collaborating 'crews', plus event-driven flows.
Daytona
Sub-90ms agent sandboxes — isolated computers with snapshots, volumes, Git and LSP tools, on Linux, Windows, or Android; AGPL self-host or managed cloud.
Dify
The visual platform for LLM apps and agentic workflows — canvas-built chatflows, RAG pipeline, agent nodes with 50+ tools, and LLMOps, self-hosted via Docker.
E2b
Open-source Firecracker-microVM sandboxes where AI agents safely run untrusted code — stateful interpreters, full Linux, pause/resume, desktop VMs.
Factory
Factory is an agent-native software development platform whose Droids plan, write, test, and ship code from the terminal, IDE, and web with org context.
Flowise
Open-source, low-code visual builder for LLM apps and AI agents — drag-and-drop to assemble chains, agents, and RAG; self-host or use Flowise Cloud.
Google ADK
Google's open-source, code-first framework to build, evaluate, and deploy AI agents. Python and Java, model-agnostic, deploys to Vertex AI Agent Engine.
Jina Reader
Prepend r.jina.ai/ to any URL and get LLM-ready markdown — JS rendering, PDFs and Office docs, image captioning, and s.jina.ai for read-the-results search.
Kilo Code
Open-source AI coding agent extension for VS Code and JetBrains, built as a superset of Roo Code and Cline, with bring-your-own-key and zero model markup.
Langchain
The provider-agnostic agent framework, post-1.0: a standard create_agent loop on the LangGraph runtime, middleware hooks, and the largest integration ecosystem.
LangGraph
A low-level library for building stateful, controllable agents as graphs, with checkpointing and human-in-the-loop.
Letta
Stateful agents from the MemGPT creators — an Apache-2.0 server with self-editing memory, and Letta Code, the memory-first model-agnostic coding harness.
Mastra
An open-source TypeScript framework for building AI agents, workflows, RAG, and tool-calling, with memory, model routing, and built-in observability.
Mem0
A memory layer for AI agents and apps — persistent, personalized long-term memory across sessions.
Modal
Serverless AI infrastructure in pure Python — GPU functions with sub-second cold starts, secure sandboxes for agent code, batch jobs, and per-second billing.
N8n
Fair-code workflow automation with native AI: a visual canvas plus code, 400+ integrations, and LangChain agent nodes; self-host free or cloud per-run.
OpenAI Agents SDK
OpenAI's lightweight, open-source framework for agents — handoffs, guardrails, sessions, and built-in tracing.
OpenHands
Open-source autonomous AI software-development agent (formerly OpenDevin) — writes code, runs commands, and browses the web in a sandbox.
Pydantic AI
Type-safe agent framework from the Pydantic team: validated structured outputs, dependency injection, durable execution, 'that FastAPI feeling.'
Skyvern
Open-source vision + LLM browser automation aimed at replacing brittle RPA — workflow builder, CAPTCHA/2FA handling, and self-host or cloud.
Stagehand
Browserbase's open-source SDK for browser agents — act, extract, observe, and agent primitives that mix natural language with code-level control.
Swe Agent
Open-source autonomous coding agent from Princeton/Stanford that turns an LLM into a software engineer to fix real GitHub issues.
Tavily
The web-access layer for agents — Search, Extract, Crawl, Map, and Research APIs purpose-built for LLMs, behind one key, with a hosted MCP server.
Trae
Trae is an AI-native IDE from ByteDance — a VS Code-style editor with a built-in Builder agent and an autonomous SOLO mode that writes code across a project.
Vercel Sandbox
Ephemeral Firecracker microVMs on Vercel for untrusted and AI-generated code — millisecond startup, Node and Python runtimes, persistent by default.
Zep
Agent memory on temporal knowledge graphs — Zep Cloud for sub-200ms context retrieval at enterprise scale, with Graphiti as its open-source graph engine.
Add Human Approval Step
Scaffold a human-in-the-loop approval gate into an agent so it pauses before a consequential action and resumes after approval.
Create Subagent
Scaffold a new Claude Code subagent definition file into .claude/agents/ with a routing-ready description, scoped tools, and a system prompt.
A2A (Agent2Agent Protocol)
A2A is an open protocol that lets AI agents discover each other's capabilities and delegate tasks across vendors, complementing MCP's tool connections.
Agent Engineering
Agent engineering is the discipline of building reliable AI agents — designing the tools, context, guardrails, evals, and recovery paths around the model.
Agent Harness
An agent harness is the system around the model that makes it an agent — the loop, tools, context management, permissions, and recovery machinery.
Agent Memory
Agent memory is how an AI agent retains information beyond its context window — working state during a task and persistent knowledge across sessions.
Agent Skills
Agent Skills are reusable procedures packaged as folders with a SKILL.md file — loaded by an AI agent on demand when a task matches, now an open standard.
Agentic AI
Agentic AI is the class of AI systems that act toward goals — planning, calling tools, and iterating on results — rather than only generating content.
AI Agent
An AI agent is an LLM-driven system that pursues a goal in a loop — calling tools, observing results, iterating — instead of returning one answer.
Computer Use
Computer use is an AI agent operating software through its real interface — reading the screen, moving the cursor, clicking, and typing like a person would.
Function Calling (Tool Calling)
Function calling lets an LLM request structured invocations of your code: describe tools with schemas, the model emits typed calls, your app executes them.
Human-in-the-Loop (HITL)
Human-in-the-loop design inserts human judgment at decisive points in an AI workflow — approving actions, resolving ambiguity, owning the irreversible steps.
ReAct (Reasoning + Acting)
ReAct is an agent loop that interleaves reasoning with tool actions — Thought, Action, Observation, repeat — so the model plans, calls a tool, and revises.