Contact Flow JSON Validator & Linter

This tool parses an exported Amazon Connect flow (Flow language, version 2019-10-30) and checks for orphaned blocks that can never run, blocks with no error branch defined, broken NextAction/Condition references that point at Identifiers that don't exist, duplicate or invalid block Identifiers, malformed ARNs in block Parameters, missing default transitions, and blocks that are never referenced by any other block.

An orphaned block is an Action defined in the flow's Actions array that can never be reached by walking NextAction, Errors, and Conditions transitions starting from StartAction. Amazon Connect will happily save a flow containing orphaned blocks, so they're easy to miss during manual review, but the logic inside them will never execute.

Most action types in the Flow language (InvokeLambdaFunction, ConnectParticipantWithLexBot, TransferContactToQueue, and more) can fail at runtime due to timeouts, missing resources, or capacity limits. If the Errors array is empty, an unhandled failure ends the contact abruptly instead of following a graceful fallback such as an apology prompt or a transfer to a queue.

The validator recursively scans every Parameters object in every block for strings beginning with arn:aws, then checks the partition, service, region, 12-digit account ID, and resource path against the format used by Lambda, Amazon Connect, Lex V2, S3, Cases, and IAM ARNs, flagging anything that doesn't match.

No. Parsing and validation run entirely in your browser with client-side JavaScript. The flow JSON you paste is never transmitted to Kloudmint or any third party — this matters because exported flows can contain Lambda ARNs, queue ARNs, and other account-specific identifiers.

No — it's a read-only linter. It tells you exactly which block Identifier has a problem and why, so you can fix it in the Amazon Connect flow designer or directly in the exported JSON before re-importing it.

2019-10-30 is the only Version value currently supported by the Amazon Connect Flow language, which every valid flow JSON export must declare at the top level alongside StartAction and Actions.

AWS documents a hard limit of 250 Actions per flow. This validator counts your blocks and warns you as you approach that ceiling.

Yes. Flow modules exported from Amazon Connect use the same Version, Actions, and Transitions structure as regular flows (an InvokeFlowModule action jumps into one), so the same reachability, error-branch, and ARN checks apply.

The Amazon Connect console mostly validates schema correctness at save time (throwing an InvalidContactFlowException for a truly broken reference) but doesn't flag orphaned blocks, missing error handling, or malformed ARNs sitting in dynamic-looking fields. This tool is a static-analysis pass you run before import, on the exported JSON itself.

Run the ARN Parameterizer first if you're moving a flow between AWS accounts, then this validator before import, and the CloudWatch Log Analyzer once the flow is live to debug any runtime failures.