Designing LLM Agents with Safe Tool Use

Agents shine when they can call tools, but safety and reliability need guardrails.

1) Structured tools

• Use JSON schemas for tool inputs.
• Validate before executing; reject malformed calls.
• Set timeouts and limits per tool.

2) Control flow

• Keep a planner/executor split for clarity.
• Add stop conditions and max steps to avoid loops.
• Provide explicit "no-op" and "ask human" paths.

3) Reliability

• Retries with backoff on transient errors.
• Circuit breakers for flaky dependencies.
• Fallback chains (cached answer -> lighter model -> main model).

4) Safety

• Policy checks before write actions.
• Red-team prompts for prompt-injection and data exfiltration.
• Maintain an allowlist for commands and destinations.

5) Observability

• Log each tool call: input, output, latency, cost, status.
• Track P50/P95 latency and error rates per tool.
• Add traces for end-to-end agent runs.

Ship agents like any other production service: tests, alerts, and rollbacks.