AI Agent Build Guides.

What is an AI agent build guide?

An AI agent build guide is a reproducible, step-by-step walkthrough for one concrete agent use case, tied to a real SDK — not pseudocode. Every guide on AgentStack ships the exact code that runs, an honest cost estimate, and the failure modes that break most first attempts. If it can't survive a cold run against your own inbox or repo, it doesn't publish.

How this hub works

This page is the map, not a guide itself. Below, every build guide currently live on AgentStack is listed with a one-line description of what it builds — click through for the full walkthrough. A second list covers the platform comparisons and ecosystem guides that sit next to the build guides in the same research process, since picking a use case and picking a platform are usually the same decision made from two directions.

The bar for a new build guide here is the same bar every post on this site has to clear: does it add something the top three Google results for that exact build don't already have? A guide that just restates a framework's quickstart docs in different words gets discarded before publish. What ships instead is the version with the OAuth gotcha nobody documents, the exclusion list that stops an agent from doing something expensive by accident, or the cost-control parameter the official cookbook mentions once and moves past.

There are two build guides live as of this writing, both built on Claude tooling — that is an honest reflection of publishing order, not a claim that Claude is the only worthwhile platform. The pipeline list below names the specific builds queued next, including ones on n8n and Make.com, so this page stays a truthful map of what exists rather than an evergreen list padded with placeholders.

The shape every build guide follows

Regardless of platform, every build guide on this site is structured the same way, because the structure is what makes a guide reproducible rather than inspirational:

1. Wire the runtime. Install the agent client (Claude Desktop, an SDK runtime, or an n8n instance) and connect exactly one tool or MCP server — not five. One working connection beats five half-configured ones.
2. Write the task-specific instruction layer. This is the prompt, SKILL.md file, or system prompt that turns generic model access into a task the agent actually does well — the triage taxonomy, the citation discipline, the routing logic.
3. Add the safety rail before the first real run. An explicit exclusion list, a human-approval gate, or a hard budget cap via a parameter like max_budget_usd. This step ships before autonomy, never after.
4. Run it against real data and record what breaks. Every guide documents the actual failure modes hit during setup — OAuth scope errors, context overload, cost overruns — because those are the parts a polished quickstart usually skips.

How to pick your first build

Three ways to find the right starting guide, fastest first:

• You have a repeatable inbox or message backlog. Start with the inbox triage build — Claude Desktop plus a Gmail MCP server, working in about two hours including OAuth setup, and it stays in human-approval mode for the entire first month by design.
• You need synthesized, cited research rather than a single search result. Start with the deep research agent build, which covers three architecture tiers from a 15-line stateless query up to parallel subagents, with the cost multiplier for each tier spelled out before you run it.
• You're not sure which platform your build should even run on. Read the platform decision guide first — it routes you to a framework in three questions (language, statefulness, MCP depth), then send you back here for the matching build once you know your stack.

The ecosystem these guides assume

Both build guides live here today run on the Claude Agent SDK or Claude Desktop's MCP client, which is a deliberate starting point, not the only supported one — the underlying patterns (stateless query, stateful multi-turn client, cost caps via max_budget_usd) port directly to LangGraph, CrewAI, or n8n once you swap the runtime. The Claude Agent SDK's Python package sits at roughly 4,800 GitHub stars with 130+ published npm versions as of March 2026 — active, fast-moving maintenance rather than a finished v1.

The MCP layer underneath every build guide has kept growing since these guides were written: tooldirectory.ai's 2026 MCP servers report puts the largest catalogues at tens of thousands of listed servers, well past the 19,000+ figure cited when the inbox triage guide first published. That growth curve is exactly why a build guide needs an explicit MCP-server-selection step rather than naming one server as canonical — the full registry landscape, including the official registry and Smithery, is mapped in the MCP and Skills ecosystem guide.

None of that scale matters if the agent you build cannot be trusted with a real inbox or a real repo. Every guide on this hub treats the safety rail — the exclusion list, the approval gate, the budget cap — as a required build step, not an optional hardening pass you get to later. That is a deliberate editorial choice, not the default in most quickstart docs, and it is the main reason a build guide here runs longer than the official cookbook it is based on.

Common questions

Do I need a paid product to follow these build guides?

No. Every build guide on this page is a free, complete walkthrough — the code and configuration shown are enough to build the agent yourself. The paid Starter Kits on /products package the same patterns into ready-made configs and prompt templates for people who want to skip the assembly step, but they are optional, not required to follow a guide.

What if I'm not using Claude?

The architecture patterns in each guide — stateless query, stateful multi-turn client, explicit cost caps, a human-approval gate before any autonomous action — are framework-agnostic. The exact code is written against the Claude Agent SDK or Claude Desktop MCP client because that is what AgentStack tested the walkthrough against, but the same shape ports to LangGraph, CrewAI, or n8n. The platform decision guide linked above helps you pick which runtime to port it to.

How often are these build guides updated?

Star counts, version numbers, and pricing figures on every live post are re-verified on a 60-day cadence per AgentStack's editorial policy. If an SDK ships a breaking change that affects a documented code pattern, the affected guide is updated within 48 hours and the page shows an updated date.

Can I suggest a build guide topic?

There isn't a public suggestion form yet — reach out via the contact page. The build guide roadmap above reflects what's already been prioritized from the site's keyword research, but a guide only gets published if it clears the same originality bar as everything else here.