[PAISEH]

Engineer AI systems, not model calls.

A principal-level handbook for designing, building, evaluating, deploying, operating, and improving reliable AI systems.

Principal means principal-engineer depth: system boundaries, tradeoffs, review gates, operational ownership, and production judgment.

PAI-SEH Method

One system for reading, designing, and reviewing AI systems

Book Lifecycle

The production AI lifecycle

Discover

Identify whether AI belongs in the problem, define the system’s purpose, and map the risks before design begins.

01

Foundations of AI Systems Engineering

Define the discipline, explain why AI systems differ from deterministic software, and establish the language used throughout the handbook.

AI system definitionCore principlesFailure taxonomy
03

Requirements, Risk, and Product Fit

Translate user needs into AI-appropriate requirements, decide whether AI is justified, and identify the blast radius before implementation.

AI fit checklistRisk registerDecision boundary worksheet

Design

Shape the system architecture, control boundaries, context strategy, prompt contract, and governance model.

02

The AI System Stack

Introduce the architecture model that connects business problem, engineering problem, evaluation, harness, context, prompt, model, and infrastructure.

System stack diagramResponsibility mapLayer tradeoffs
04

Prompt Engineering for Production

Move beyond prompt tricks into durable instruction design, prompt contracts, examples, structured outputs, and prompt change management.

Prompt specOutput contractPrompt review checklist
05

Context Engineering and Retrieval

Design the data, retrieval, ranking, memory, compression, and authorization layer that makes AI behavior grounded and useful.

Context assembly planRetrieval eval setSource trust matrix
06

Harness Engineering and Control Loops

Build the operating layer around the model: routing, retries, validation, fallbacks, state transitions, approvals, and traceability.

Harness diagramFallback planValidation matrix
09

Security, Privacy, and Governance

Address prompt injection, data leakage, model and supply-chain risk, privacy boundaries, compliance, retention, and responsible AI review.

Threat modelData handling policyGovernance review

Develop

Connect models to tools, workflows, deployment paths, and reference architectures that can be built and reviewed by engineering teams.

07

Tool Use and Agentic Workflows

Safely connect AI systems to tools, APIs, files, databases, workflows, and long-running tasks without losing control of authority.

Tool permission matrixApproval policyIdempotency checklist
10

Deployment and Runtime Architecture

Package, deploy, version, route, scale, and roll back AI systems across model versions, prompts, retrieval indexes, tools, and policies.

Release manifestVersioning modelRollback procedure
12

Reference Architectures and Design Reviews

Compare common patterns including RAG, copilots, workflow agents, AI search, human-in-the-loop systems, and hybrid architectures.

Pattern catalogDesign review questionsArchitecture tradeoff table

Evaluate

Turn quality, safety, and release readiness into an engineering system rather than a subjective judgment.

08

Evaluation Engineering

Create the quality system for AI: scenario suites, golden datasets, adversarial tests, human review, production sampling, and release gates.

Eval planHuman rubricLaunch threshold table

Operate & Improve

Run AI systems in production, learn from failures, and improve the product through traces, incidents, case studies, and reusable runbooks.

11

Observability, Incidents, and AI SRE

Operate AI systems using traces, logs, semantic quality signals, cost telemetry, drift monitoring, incident response, and continuous improvement.

Trace schemaIncident runbookQuality dashboard
13

Case Studies

Walk through realistic systems such as customer support, enterprise search, document intelligence, financial copilots, coding assistants, and operations agents.

Failure analysisArchitecture walkthroughLessons learned
14

Templates, Checklists, and Runbooks

Provide reusable operating assets that teams can copy into real projects and adapt for their own review process.

Design docLaunch checklistOperations runbook

Core Disciplines

The engineering disciplines used throughout the handbook

Signature Framework

The design review before an AI system gains power.

A principal-level review sequence for expanding autonomy, adding tools, exposing users, or increasing production risk.

Open framework
  1. Define the business problem, engineering problem, and why AI is the right mechanism.
  2. Draw the system boundary across user intent, context, model, tools, state, policy, review, and observability.
  3. Name the decision surface: what the AI may recommend, draft, decide, execute, or refuse.
  4. Map the blast radius across quality, security, privacy, reliability, cost, latency, and trust.
  5. Set the release gate: eval thresholds, human review, fallback behavior, rollback, and production monitoring.

Reusable Assets

Templates for real engineering reviews and operations

Release Scorecard

Five questions before production launch