Glossary
Circuit Breaker (Tool Calls)
A safeguard that halts an agent's retry loop after a fixed number of identical tool-call failures, commonly three, instead of retrying indefinitely. Prevents cost runaway and stops a single malformed or hallucinated tool call from corrupting every downstream reasoning step.
Without one, a single malformed tool response can trigger an identical-retry loop that exhausts a budget in hours, not days.
Why three retries specifically?
Three is the common default because it balances tolerance for transient failures — a flaky network call, a momentary rate limit — against runaway cost: enough attempts to not overreact to a one-off blip, but few enough that a genuine failure loop gets stopped before it burns significant budget. Teams tune this based on their own cost tolerance and how flaky their tool integrations are.
Where this comes up
AI Agent Failure Modes in Production
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