Parallel Tool Calls
When an agent fires off several independent tool calls at once instead of one after another.
Think of it like
Ordering the appetizer, main, and dessert all at once instead of waiting to finish each before asking for the next.
Example
Asked to compare three products, the agent looks all three up simultaneously rather than sequentially, cutting the wait to a third.
How it actually works
When tasks don’t depend on each other, running them in parallel is a big latency win — the model emits multiple calls in one turn and the runtime executes them together. The catch is that many tasks are actually dependent (you need result A to know what to look up for B), and the model doesn’t always tell the difference, so it sometimes parallelizes things it shouldn’t. Handling partial failures across the batch adds complexity too.
For product teams
Parallel calls make agents feel much faster on independent work — but only when the steps truly don’t depend on each other.
For engineers
The model emits multiple tool calls in one turn; the runtime dispatches them concurrently and joins the results.
Related
- Tool Calling — The single-call version.
- Tool Chaining — Chaining calls when they do depend on each other.
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