Everyone's building AI agents. The demos are impressive. The production deployments? Mostly a disaster. Here's what we've learned from running agents in production across multiple enterprise environments.

The Demo-to-Production Gap

An AI agent that works in a demo has exactly one thing going for it: a controlled environment. In production, you face:

  • Unpredictable user inputs that break your carefully crafted prompts
  • API rate limits that cause cascading failures
  • Model latency spikes that timeout downstream systems
  • Hallucinations that corrupt real data
  • Cost runaway when agents loop or over-tool

None of these show up in demos. All of them show up in production within the first week.

Architecture Patterns That Work

1. The Guard Rail Pattern

Every agent action should pass through a validation layer before execution. Not just input validation — output validation. Before an agent writes to a database, sends an email, or modifies a file, a deterministic guard rail checks:

  • Is this action within the agent's authorized scope?
  • Does the output conform to expected schemas?
  • Is the magnitude of change reasonable? (Don't delete 10,000 rows when asked to clean up duplicates)

2. The Circuit Breaker Pattern

Borrowed from microservices architecture: if an agent fails N times in a row, stop trying and alert a human. This prevents the nightmare scenario where an agent keeps retrying a broken operation, burning tokens and potentially corrupting state with each attempt.

We implement this at two levels: per-tool (if a specific API keeps failing) and per-task (if the overall goal isn't making progress).

3. The Audit Trail Pattern

Every agent action, every tool call, every decision point gets logged to an immutable audit trail. Not just for debugging — for compliance, for rollback, and for improving the agent over time.

We log: the prompt, the model's reasoning, the tool calls, the results, and the final output. This makes post-incident analysis actually possible.

4. The Human-in-the-Loop Escalation

Design your agent to know when it's uncertain. This sounds obvious, but most agent frameworks don't handle it well. We use confidence scoring: if the agent's certainty drops below a threshold for a high-stakes action, it pauses and asks a human.

The key is calibrating the threshold. Too low, and the agent escalates everything (defeating the purpose). Too high, and it confidently does the wrong thing.

Monitoring: What to Watch

Standard application monitoring isn't enough for AI agents. You need:

  • Token consumption per task. A sudden spike means the agent is looping or over-reasoning.
  • Tool call patterns. If an agent is calling the same tool 10 times in a row, something is wrong.
  • Completion rates. What percentage of tasks reach a successful end state vs. timeout, error, or escalation?
  • Latency distribution. Not just average — the P95 and P99 matter because that's where users lose patience.
  • Cost per task. Know your unit economics. If a task that should cost $0.05 is costing $5, investigate immediately.

Failure Modes You'll Hit

The Infinite Loop

Agent tries action → gets error → tries slightly different action → gets same error → repeat forever. Solution: track action history within a session and hard-limit retries.

The Confident Hallucination

Agent generates a plausible-sounding answer that's completely wrong, and acts on it. Solution: fact-check critical outputs against ground truth before acting. Use retrieval, not generation, for factual claims.

The Scope Creep

User asks agent to "clean up the data" and it deletes half the database. Solution: explicit scope boundaries and magnitude limits on every destructive operation.

The Token Bomb

Agent encounters a large context (big file, long conversation) and costs spike 100x. Solution: context windowing, summarization, and hard token budgets per task.

Our Stack

After iterating through multiple frameworks, here's what we've settled on:

  • Orchestration: Custom lightweight layer (not LangChain — too much abstraction for production use)
  • Models: Claude for reasoning-heavy tasks, GPT-4o for speed-sensitive ones, open-source for high-volume/low-stakes
  • Tool execution: Sandboxed environments with resource limits
  • Monitoring: Custom dashboards built on structured logs
  • Evaluation: Weekly eval runs against regression test suites

The Honest Truth

AI agents in production are hard. They're non-deterministic systems running in deterministic environments, and every edge case is a potential incident. But when they work — when they're properly guarded, monitored, and scoped — they're transformative.

The difference between a toy demo and a production system is about 10x the engineering effort. Budget for it.