AvailableUtilities

Random Bytes

Create a secret. Keep it out of the conversation.

Set up local helper How it works

1 credit per jobMCP tool: get_random_bytes

Exampleget_random_bytes

Before

label · n · operation_idAsk for the amount your application needs

After

The bytes stay local

Private file or vault reference

The owner chooses storage and generation policy. A new operation ID creates a new version.

What it does

Hardware randomness, combined with your computer’s secure generator.

MCPBytes Vault receives encrypted hardware-generated randomness, combines it with fresh randomness from your operating system, and saves the result locally. Use it for raw key material and random tokens. Your agent gets a file or vault reference, so it can work with the result without putting the bytes into its response. A local helper keeps the final secret on your computer.

Size: 1–64 bytes per operation
Generation: Hardware contribution + local OS randomness
Saved locally: Private file or native credential store
Agent receives: Reference, size and version; no secret bytes
Retry: Reuse the operation ID to recover its completed receipt

A reference, ready for your app

Save raw bytes for your application’s cryptographic library. They are not automatically a key pair or an encoded password.

Choose your local store

Use a private file, Windows Credential Manager, macOS Keychain or Linux Secret Service.

An explicit policy

Require a remote contribution, allow reported local fallback on temporary unavailability, or choose local-only generation.

Pricing

Pay per job, in credits.

1 credit per job. Local-only generation makes no API call. Failed API jobs are refunded; a completed remote contribution is charged even if local verification or saving later fails.

Pricing details

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Available now

100free credits when you sign up

Every MCPBytes tool, one credit balance
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Each tool states its price before you run it
Failed API jobs cost nothing

Get an API key Set up local helper

Price per job

Random Bytes

Per job: 1 credit

Limits

Bytes: 1–64 per request
Results: Encrypted: 5 minutes · Local: owner-managed
At a time: 1 job

Use it with your agent

One local tool. A saved-secret reference.

Install MCPBytes Vault and connect it as a local MCP server. The owner sets the API key, trusted public pins and storage policy; the agent supplies only these arguments.

Local MCP tool: get_random_bytes

labelOwner-approved prefix: A name for the secret, using letters, digits, underscores or hyphens.
n1–64: Number of bytes your application needs.
operation_idStable ID: Reuse after an uncertain reply. Use a new ID to create a new immutable version.

A successful response contains the reference, label, version, byte count, storage backend and generation mode. The helper exposes no plaintext read or export tool.

Download and set up the local helper

Building your own local client?

The hosted endpoint accepts a fresh recipient public key and its bound request identity. A custom local client must authenticate and decrypt the response, mix it with local OS randomness, and save it privately. Encrypted responses expire five minutes after admission and are removed by the scheduled cleanup; billing metadata remains. Never send a private key to the API or chat.

Encrypted API schema

Set up the local helper.

Install MCPBytes Vault and connect it as a local MCP server. The owner sets the API key, trusted public pins and storage policy; the agent supplies only these arguments.

Downloads and setup Get API Key