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AActionAWS BedrockUpdated May 2026

How do I run RAG retrieval against a Bedrock Knowledge Base?

Short answer: Drop the "AWS BedrockKnowledge Bases Retrieve" action anywhere in your workflow, map the inputs from upstream nodes, and publish.

Inputs

The fields this action accepts.

Every field can be mapped from an upstream trigger, AI step, table row, or hard-coded literal.

FieldTypeRequiredDescription
Knowledge Base ID
knowledge_base_id
stringRequiredKnowledge Base ID (required)
Query
query
stringRequiredQuery (required)
Number of Results
number_of_results
stringOptionalNumber of Results
Sample request
{
"knowledge_base_id": "{{trigger.knowledge_base_id}}",
"query": "{{trigger.query}}",
"number_of_results": "{{trigger.number_of_results}}"
}
Returns
{
"retrievalResults": [
{
"score": 0.91,
"content": {
"text": "..."
},
"location": {
"type": "S3",
"s3Location": {
"uri": "s3://x/y"
}
}
}
]
}

Use these fields in downstream nodes for routing, logging, or error handling.

Triggered by

Apps that pair well as the trigger for Knowledge Bases Retrieve.

Any of these apps can fire this action as part of a workflow.

FAQ

Questions about Knowledge Bases Retrieve.

What does the Knowledge Bases Retrieve action do in AWS Bedrock?
Semantic-searches a configured Bedrock Knowledge Base (which sits on top of S3-stored documents indexed into a vector store) and returns the most relevant chunks with citations. Saves you from building and managing your own RAG ingestion pipeline.
What inputs does Knowledge Bases Retrieve require?
Required: Knowledge Base ID, Query. Every input accepts a static value or a variable from any upstream node in your workflow.
Can I use dynamic inputs from earlier workflow nodes?
Yes. Any field on this action can pull values from upstream nodes, whether that's a form response, a trigger payload, an AI output, or a lookup result.
What happens if AWS Bedrock returns an error?
The workflow pauses on the failed node, the error message is captured in the run log, and you can retry the run with one click. Auto-retry policies are configurable per workflow with exponential backoff up to 5 attempts.
Does Knowledge Bases Retrieve support batch operations?
Yes. Run Knowledge Bases Retrieve inside a Loop node to process arrays. Tiny Command handles AWS Bedrock's rate limits automatically so you don't have to throttle manually.
More actions

Other AWS Bedrock actions.

Send knowledge bases retrieve from your workflows.

Triggered by anything in the catalog. Free tier available. No credit card.