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From prompt to production AI agent.

A useful production agent is a controlled workflow with tools, evidence, permissions, tests, human decisions and an operating owner—not a clever prompt wrapped in a chat window.

12 minute readIntermediateReviewed 12 Aug 2026

What you will learn

  • How to choose a bounded agent use case.
  • How tools, context, approvals and guardrails fit together.
  • How to evaluate quality before and after release.
  • Which artifacts make an agent project defensible in an interview.

1. Start with a decision, not a model

Choose one user, one measurable job and a clear boundary. “Answer employee policy questions and create an HR case when evidence is insufficient” is testable. “Build an HR super-agent” is not. Write the success condition, prohibited actions, escalation rule and data boundary before choosing a framework.

ScopeDesignEvaluateReleaseObserve

2. Turn the job into an explicit workflow

List the information the agent needs, the tools it may call and the state that must survive between steps. Prefer a deterministic workflow when the route is already known. Use an agent when the system genuinely needs to select among tools or decide the next step from changing context.

Instructions

Define the objective, constraints and completion criteria.

Tools

Use narrow contracts, validated inputs and typed outputs.

Handoffs

Transfer work only with the context the next owner needs.

State

Persist only what the workflow requires and policy allows.

3. Treat context as governed input

More context is not automatically better. Retrieval should return current, permission-appropriate evidence with enough metadata to verify the answer. Tool responses, conversation state and retrieved documents all need size, sensitivity and freshness rules. If MCP is used, each server is a trust boundary with its own authorization and audit needs.

4. Put controls around consequential actions

5. Evaluate the behavior, not the demo

Build an evaluation set from normal tasks, edge cases, policy refusals, tool failures and adversarial inputs. Measure task completion, evidence quality, correct tool selection, argument validity, policy adherence, handoff quality, latency and cost. A change should not ship when it improves a showcase answer but breaks a critical case.

LayerWhat to testEvidence
AnswerCorrectness, grounding, relevanceReference answer and cited source
Tool useRight tool, valid arguments, safe retriesTrace assertions
PolicyPermissions, refusal, approvalExpected control outcome
SystemLatency, cost, availabilityOperational thresholds

6. Release with an owner and feedback loop

Use versioned prompts and tool schemas, a staged rollout, dashboards and rollback criteria. Review traces for recurring failure patterns and convert them into new evaluation cases. Production feedback improves the system only when it becomes structured evidence.

The strongest agent portfolio is not the one with the most tools. It is the one that can explain its boundaries, prove its behavior and fail safely.

Portfolio artifact

Document one agent with a one-page problem brief, workflow diagram, tool contracts, threat model, evaluation dataset, scored results, sample traces and release checklist. That package demonstrates more engineering judgment than an untested chatbot repository.

Primary sources

Written by Digital Edify curriculum team · Technical review required quarterly · Last reviewed 12 August 2026