Omniseal for Claude

Conceal a file inside a supported cover, retrieve the hidden file with its private seed, verify a seal, or produce a clean cover. Operations return new files and preserve the originals.

Connect

In Claude, open Customize → Connectors → Add custom connector.
Name it Omniseal and enter the URL below.
Choose No sign-in, add the connector, then connect and enable it in your conversation. Organization accounts may require an owner.

https://api.purecipher.com/mcp?platform=claude

No PureCipher account or API key is required for this endpoint. Anyone with the endpoint URL can call it. The private seed used for file operations is not an account password.

Four operations

Seal files: choose a cover, a secret file, and a private seed; receive a new sealed file.
Retrieve secret file: supply a sealed file and the matching seed to recover the hidden file.
Verify sealed file: check whether the file contains an intact Omniseal seal.
Remove hidden file: supply the sealed file and seed to create a clean cover.

File inputs and limits

Supply a file's real name and either a publicly fetchable HTTPS download URL or its exact base64 bytes. Claude attachments and local file paths are not automatically accessible to the service. Use URLs only when you are authorized to share their contents with PureCipher.

{"file_name":"cover.png","download_url":"https://your-host.example/cover.png"}

PNG, PDF, DOCX, and XLSX are covered by SDK tests. Inputs are limited to 6 MB per file and 10 MB combined for sealing. Claude results are capped at 140,000 serialized characters, generally allowing generated files below about 100 KB. Larger results return an explicit size error. This connector does not provide hosted output download links or an automatic upload picker. Outputs are binary MCP resources; rendering and saving depend on the Claude client.

Try synthetic review files

These fixtures contain only demonstration content. The review seed is omniseal-review-2026.

Example: “Use Omniseal to verify https://api.purecipher.com/fixtures/review-sealed.png, named review-sealed.png.”

Processing and support

File contents, names, and the operation seed are sent to PureCipher's hosted service for processing with its Omniseal SDK. The service does not request access to your Claude history, memory, or account file store. Request metadata is logged for operations and security. Do not submit account passwords as private seeds. Omniseal is not a password recovery service or general-purpose encryption tool.