Add Signet plugin — local-first cryptographic signing for agent workflows

[willamhou]

Plugin: Signet

Cryptographic action receipts for Dify agent workflows. Ed25519 signing, hash-chained audit trail, offline verification.

Key difference from existing signing plugins: No API key, no SaaS, no network dependency. Signing keys and audit logs stay on your infrastructure.

Tools

Tool	Description
Sign Action	Ed25519 sign any tool call, append to hash-chained audit log
Verify Receipt	Offline signature verification — no network needed
Audit Query	Query local audit trail by time range or tool name

Setup

1. Install plugin
2. Optionally set a Key Name (default: dify-agent)
3. No API keys, no accounts — auto-creates Ed25519 identity on first use

Why local-first matters

	Signet	SaaS signing
API key required	No	Yes
Data leaves infrastructure	No	Yes
Offline verification	Yes	No
Key custody	You	Provider

Compliance

Signed audit trails support SOC 2 (CC7.2, CC7.3), ISO 27001 (A.8.15), EU AI Act Article 12, and DORA. See full compliance mapping.

Source

• Plugin repo: https://github.com/Prismer-AI/dify-plugin-signet
• Signet: https://github.com/Prismer-AI/signet
• PyPI: signet-auth

Happy to submit a PR if there's interest.

[Keesan12]

Local-first signing is the right default. I would just make the receipt carry lifecycle state too, not only the signature.

Useful fields would be: tool name, action hash, decision, status, timestamp, and whether the action was committed, denied, or later rolled back. That keeps the audit trail small, verifiable offline, and easier to query when someone asks why the workflow stopped.