AI engineering glossary · Agents tools MCP
What is idempotency (tool calls)?
Idempotency (tool calls) (also called Idempotent tool call): The property that running the same tool call twice has the same effect as running it once. Agents may retry or repeat calls after timeouts, so actions such as payments or emails should carry an idempotency key to avoid duplicates.
Idempotency (tool calls): an example
A refund tool takes idempotency_key='order-4471-refund', so a retried call does not pay Rs 1,200 twice.
Related terms
More Agents tools MCP terms
- Indirect prompt injection
- Interrupt (agent)
- JSON-RPC
- Kill switch
- LangChain
- LangGraph
- Least privilege for agents
- LlamaIndex
Where you learn it
Idempotency (tool calls) is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.