> ## Documentation Index > Fetch the complete documentation index at: https://developers.fireblocks.com/llms.txt > Use this file to discover all available pages before exploring further. # Add a new signing key > Adds a new signing key to the workspace. The added key will be linked to the specific Fireblocks agent user ID. The same user will receive the proof of ownership message to be signed, and upon successful proof, the key will become enabled. ## OpenAPI ````yaml https://docs.fireblocks.com/api/v1/swagger.yaml post /key_link/signing_keys openapi: 3.0.0 info: title: Fireblocks API description: > Fireblocks provides a suite of applications to manage digital asset operations and a complete development platform to build your business on the blockchain. - Visit our website for more information: [Fireblocks Website](https://fireblocks.com) - Visit our developer docs: [Fireblocks DevPortal](https://developers.fireblocks.com) version: 1.6.2 contact: email: developers@fireblocks.com servers: - url: https://api.fireblocks.io/v1 description: Fireblocks Production Environment Base URL - url: https://sandbox-api.fireblocks.io/v1 description: Fireblocks Sandbox Environment Base URL security: [] paths: /key_link/signing_keys: post: tags: - Key Link (Beta) summary: Add a new signing key description: >- Adds a new signing key to the workspace. The added key will be linked to the specific Fireblocks agent user ID. The same user will receive the proof of ownership message to be signed, and upon successful proof, the key will become enabled. operationId: createSigningKey parameters: - $ref: '#/components/parameters/X-Idempotency-Key' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateSigningKeyDto' responses: '201': description: Newly created signing key headers: X-Request-ID: $ref: '#/components/headers/X-Request-ID' content: application/json: schema: $ref: '#/components/schemas/SigningKeyDto' default: $ref: '#/components/responses/Error' x-codeSamples: - lang: TypeScript source: >- const response: Promise> = fireblocks.keyLinkBeta.createSigningKey(keyLinkBetaApiCreateSigningKeyRequest); - lang: Java source: >- CompletableFuture> response = fireblocks.keyLinkBeta().createSigningKey(createSigningKeyDto, idempotencyKey); - lang: Python source: >- response = fireblocks.key_link_beta.create_signing_key(create_signing_key_dto, idempotency_key); components: parameters: X-Idempotency-Key: name: Idempotency-Key in: header description: >- A unique identifier for the request. If the request is sent multiple times with the same idempotency key, the server will return the same response as the first request. The idempotency key is valid for 24 hours. required: false schema: type: string schemas: CreateSigningKeyDto: type: object properties: signingDeviceKeyId: type: string maxLength: 256 example: MyKey1 description: >- The ID, name or label of the key specified on the customer's signing device. signedCertPem: type: string example: '-----BEGIN CERTIFICATE ... END CERTIFICATE-----' description: >- The signed certificate that includes the public key PEM of the signing key, signed by a validation key. agentUserId: type: string minLength: 36 maxLength: 36 example: d18847b5-1df6-4c46-8f99-5cce47284529 description: Id of user to which this key belongs proofOfOwnership: type: object description: An object containing proof of ownership for the signing key. properties: message: description: >- The message to be signed by the key as proof of ownership. 64 to 1024 bytes in hexadecimal format. type: string minLength: 64 maxLength: 2048 signature: description: The signature of the message. 64 bytes in hexadecimal format. type: string minLength: 64 maxLength: 128 required: - message - signature required: - signingDeviceKeyId - signedCertPem - agentUserId SigningKeyDto: type: object properties: keyId: type: string minLength: 36 maxLength: 36 example: 46a92767-5f93-4a46-9eed-f012196bb4fc description: External signing key id set by Fireblocks. signingDeviceKeyId: type: string maxLength: 256 example: MyKey1 description: >- The ID, name or label of the key specified on the customer's signing device. publicKeyPem: type: string example: '-----BEGIN PUBLIC KEY ... END PUBLIC KEY-----' description: PEM encoded public key algorithm: type: string example: ECDSA_SECP256K1 description: >- Algorithm and curve used for the signature. Can be: ECDSA_SECP256K1 or EDDSA_ED25519 enabled: type: boolean example: true description: True if the signing key is enabled vaultAccountId: type: number nullable: true example: 10 description: Id of the vault account which this key is linked to agentUserId: type: string minLength: 36 maxLength: 36 example: d18847b5-1df6-4c46-8f99-5cce47284529 description: Id of user that represent agent servers that can sign with the key createdAt: type: number example: 124757537 description: Creation date (timestamp) in milliseconds. required: - keyId - signingDeviceKeyId - publicKeyPem - algorithm - enabled - vaultAccountId - agentUserId - createdAt ErrorSchema: type: object properties: message: type: string code: type: number headers: X-Request-ID: schema: type: string description: >- Unique ID correlated to the API request. Please provide it in any support ticket you create or on Github issues related to Fireblocks SDKs responses: Error: description: Error Response headers: X-Request-ID: $ref: '#/components/headers/X-Request-ID' content: application/json: schema: $ref: '#/components/schemas/ErrorSchema' ````