AI Agents Fundamentals Best Practices
Ten habits for deciding agent vs script vs copilot before you invest in loops, tools, and ops.
Use this list when a stakeholder says "we should build an agent" and you need a calm, engineering-first answer.
How to Use This Checklist
- Work top to bottom; earlier rules are cheaper filters.
- Tick items that are true for your candidate problem.
- If several critical boxes stay unchecked, ship a script, workflow, or copilot instead.
- Re-run the list after demos when hype is highest.
- Keep the filled checklist next to the design doc for review.
A - Problem Fit
- 1. Write the goal as a verifiable outcome. "Tests pass on branch," "ticket fields updated," or "cited report with N sources" beats "be helpful."
- 2. Prefer a script or workflow when the path is known. If you can flowchart every step without surprises, automation without an agent loop is usually better.
- 3. Require branching on intermediate results before choosing an agent. Agents earn their cost when next actions depend on tool observations you cannot hardcode.
- 4. Default to copilot when judgment is subjective or stakes are high. Draft-and-approve is a feature, not a failure of ambition.
B - Scope and Autonomy
- 5. Start at the lowest autonomy level that works. Single-turn tools before multi-turn; supervised goals before long-running exception-only modes.
- 6. Cap the action space deliberately. Few well-described tools beat a kitchen-sink registry that confuses selection and expands blast radius.
- 7. Separate read paths from write paths. Prove value on read-only tools first; gate irreversible tools with approvals and limits.
C - Runtime Discipline
- 8. Ship stop conditions with the first prototype. Max turns, timeouts, and cost budgets are product requirements, not polish.
- 9. Log traces as first-class artifacts. Every demo and production run should leave tool names, args (redacted), observations, and stop reasons.
- 10. Define eval and escalation before marketing the agent. Golden tasks, failure injection, and a human handoff path decide whether the system is real.
Applying the Habits in Order
| Stage | Habits | Exit criterion |
|---|---|---|
| Problem intake | 1-4 | Clear goal, known path vs true branching, risk posture |
| Design | 5-7 | Autonomy level + tool list + write policy documented |
| Prototype | 8-9 | Loop stops safely; traces reviewable |
| Launch gate | 10 | Eval baseline + escalation path signed off |
Quick "Do Not Build an Agent" Signals
- Success cannot be checked without a senior expert every time.
- Tools do not exist yet and would take longer than the agent itself.
- The org will not fund observability or incident response.
- Latency must be a single cheap model call.
- The request is really "chat UI over our docs" (grounded assistant, not agent).
FAQs
How many checklist items must pass?
Treat 1, 8, and 10 as mandatory. If 2 is true (path fully known), stop and build a workflow instead of forcing an agent.
Can we prototype without evals?
You can spike, but do not call it production-ready. Habit 10 is the launch gate, not a research nice-to-have.
What if leadership already announced an agent?
Ship a supervised, narrow slice that meets the checklist. Rename marketing later if needed; do not expand write tools to match the press release.
Is a single tool call "enough" to count as an agent project?
It may be the right product. Call it tool-augmented completion or Level 1 autonomy so ops expectations stay honest.
How do these habits relate to multi-agent designs?
Apply them per agent and to the orchestrator. Multi-agent multiplies cost and failure modes; it does not relax stop conditions or evals.
What document should this checklist live in?
A one-page ADR or design brief: goal, autonomy level, tools, budgets, eval set, escalation owner.
How often should we revisit after launch?
After incidents, tool changes, and quarterly reviews. Autonomy should be able to decrease.
Do open-source frameworks change the checklist?
They change implementation speed, not fitness. A framework without habits 8-10 still yields fragile agents.
What is the most common failed "agent" project?
A chatbot with extra marketing and one brittle integration, no traces, and no success metric beyond "feels smart."
When is an agent clearly the right call?
Multi-step work with stable tools, automatic or cheap verification, acceptable latency, and a team willing to operate traces and budgets.
Should product managers fill this list alone?
No. Pair PM + eng + security for write tools. Habit 7 especially needs shared ownership.
How does this connect to later fundamentals sections?
Loops, architectures, and model choice assume you already passed problem fit. Skipping this list is the root cause of many later "runaway agent" fires.
Related
- What Actually Makes Software an "Agent"? - definition you are scoping against
- Autonomy Levels - pick the lowest viable rung
- What an Agent Can and Can't Do Reliably Today - capability reality check
- Agents vs Chatbots vs Assistants vs Copilots - choose the right product pattern
- Scope Rules: When a Problem Actually Needs an Agent - rules-group expansion of fit criteria
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