> For the complete documentation index, see [llms.txt](https://docs.contextual.io/documentation-and-resources/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.contextual.io/documentation-and-resources/components-and-data/agents/scale-and-performance/parallel-instances.md).
# Parallel Instances
On paid service plans, you can configure Agents to scale to multiple instances. Scaling can happen in two ways.
For HTTP and Event Agents, you can scale based on Compute. If compute hits a given threshold (e.g. - 80%), Contextual will automatically scale up another Agent instance.
For Event Agents, you can also scale based on message lag. Based on the number of messages a given agent is required to process it can dynamically scale up to handle the increased message volume.
Compute-Based Agent Scaling
Message Lag-Based Agent Scaling
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# Agent Instructions
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## Querying This Documentation
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