# Invoke Lambda function asynchronously

Canonical URL: https://docs.fuse.init.inc/integrations/aws/actions/lambda.functions.invoke_async

Accept a Lambda Event invocation (HTTP 202). Provider acceptance is not function completion; Lambda may retry failures and deliver duplicates, so handlers must be idempotent with a failure destination or DLQ. Payload is JSON text capped at 256 KiB. Unsafe with one SDK attempt and no client dispatch retry. Excluded from MCP. Requires lambda:InvokeFunction.

Action ID: `lambda.functions.invoke_async`
Provider: AWS (`aws`)
Contract version: 1

## Risk and exposure

- Risk: Write
- Idempotency: Unsafe — Retries may duplicate side effects; callers must coordinate carefully.
- Availability: Default
- Exposure: REST, SDK
- MCP hints: readOnly=false, destructive=false, idempotent=false, openWorld=true

## Required scopes

- `lambda:InvokeFunction`

## Input schema fields

- `function_name`
- `payload`
- `region`
- `qualifier`

## Output schema fields

- `accepted`
- `status_code`

Provider overview: https://docs.fuse.init.inc/integrations/aws
Actions index: https://docs.fuse.init.inc/integrations/aws/actions
Exact canonical JSON contract: https://docs.fuse.init.inc/api/catalog/v1/providers/aws/actions/lambda.functions.invoke_async
Deployment-effective discovery: https://api.fuse.init.inc/v1/tenants/%7Btenant_id%7D/providers/aws/actions