Building a 12-Factor Agents App in TypeScript | CodeSignal Learn

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Building a 12-Factor Agents App in TypeScript

Artificial Intelligence

4 courses

59 practices

11 hours

Learn the 12-Factor Agents methodology by building a complete agentic application in TypeScript. Master structured outputs, function calling, context management, stateless reducers, pause/resume functionality, human-in-the-loop workflows, and API integration with database persistence.

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Tool Integration and Action Execution

Tools you'll use

Express.js

JSON

Markdown

NodeJS

OpenAI

SQLite

TypeScript

Course 1

Understanding the 12-Factor Agents Methodology

4 lessons

12 practices

Discover why reliable AI agents require more than off-the-shelf frameworks. This foundational course introduces the 12-Factor Agents methodology and the principles that separate flashy demos from production systems. Learn how sound software engineering, targeted LLM integration, and twelve clear principles yield maintainable, scalable, trustworthy agentic apps.

Course 2

Foundations of Agentic Tool Use in TypeScript

4 lessons

20 practices

Master the practical building blocks of agentic systems in TypeScript. Covering Factors 1, 3, 4, 8, and 9, this course teaches structured model outputs with the official OpenAI TypeScript SDK, typed tool schemas, explicit context management, and controlled loops that execute tools and compact errors back into context.

Course 3

Developing a Stateless Agent in TypeScript

3 lessons

14 practices

Turn scripts into reusable components by embracing strict types and stateless design. With Factors 2, 5, 10, and 12, students externalize prompts, unify execution and business state, and build a reducer-style agent that takes state in and returns state out.

Course 4

Exposing Agents with Simple APIs in TypeScript

5 lessons

13 practices

Transform your stateless agent logic into a backend service. Applying Factors 5, 6, 7, and 11, this course shows how to decouple agent execution from user interfaces. Persist unified state in a relational database, orchestrate runs through REST endpoints, control Launch/Pause/Resume, and connect autonomous execution with human intervention through tool calls.

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