deepseek-harness/packages/util/crypto/README.md

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description: "Cross-runtime UUID generation for maintainers replacing secure-context-only crypto.randomUUID calls."

kind: "package-library"

dsh-util-crypto

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Summary

Zero-dependency browser-safe UUID and byte-encoding helpers. UUID minting uses crypto.getRandomValues, the one random primitive every shipped context provides. crypto.randomUUID is a secure-context Web API: a page or worker served over plain HTTP on a LAN address (the browser preview deployment) has no such method, so code that must run there cannot call it. The repository-wide no-restricted-properties lint rule points crypto.randomUUID callers here; Node-only code importing randomUUID from node:crypto stays as it is.

Table of Contents

• Use this package
• API
• Model Experience
• Known Limitations and Deferred Work
• Dev Note

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Use this package

It is a library, not a service or plugin: no ctx, registers nothing, holds no state.

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API

import { bytesToBase64, randomUUID, type Uuid } from '@deepseek-ai/dsh-util-crypto'

Export	Role
bytesToBase64(data)	Canonical base64 for a byte array, encoded in bounded chunks.
randomUUID()	Random RFC 9562 v4 UUID string, minted from crypto.getRandomValues. Drop-in for crypto.randomUUID().
Uuid	The five-group UUID string type, matching crypto.randomUUID's declared return shape.

Model Experience

Indirectly, through consumers that mint request, session, and attachment identifiers with it, none of which enter prompts as semantic content.

KV Cache effect

No direct invalidation; identifier-minting consumers own any request changes.

Known Limitations and Deferred Work

• v4 only — no other UUID versions, namespaces, or parsing; consumers needing more should take a real UUID dependency.
• Uniqueness is probabilistic — 122 random bits, the same guarantee crypto.randomUUID gives; nothing here detects collisions.

Dev Note

Working context for maintainers — click to expand

None.

Runtime invariant: No companion is published. This pure utility owns no event stream or mutable runtime data; its value algebra is enforced by unit tests.