---
title: "Submit sync committee signatures to node"
method: POST
path: "/eth/v1/beacon/pool/sync_committees"
tags: ["Beacon", "ValidatorRequiredApi"]
---

# Submit sync committee signatures to node

`POST /eth/v1/beacon/pool/sync_committees`

## Request

- Base URL: `eth2-beacon-mainnet.nodereal.io/v1/api_key` (relative, and the document’s source URL is not known)
- URL: `eth2-beacon-mainnet.nodereal.io/v1/api_key/eth/v1/beacon/pool/sync_committees`
- Auth: none declared

Submits sync committee signature objects to the node.

Sync committee signatures are not present in phase0, but are required for Altair networks.

If a sync committee signature is validated successfully the node MUST publish that sync committee signature on all applicable subnets.

If one or more sync committee signatures fail validation the node MUST return a 400 error with details of which sync committee signatures have failed, and why.

## Request body

- object[]
  - `slot` string
  - `beacon_block_root` string
  - `validator_index` string
  - `signature` string

## Response `200`

Sync committee signatures are stored in pool and broadcast on appropriate subnet

## Other responses

- `400`: Errors with one or more sync committee signatures
- `500`: Beacon node internal error.

---

[API](https://skmtc.dev/nodereal/apis/eth-beacon-node-api.md) - [All operations](https://skmtc.dev/nodereal/apis/eth-beacon-node-api/llms.txt) - [OpenAPI document](https://skmtc.dev/nodereal/apis/eth-beacon-node-api/revisions/1878ea8657a1?raw)