[Feature Request]: Add Creduent zero-trust agent identity verification plugin for ADK

[cyberfascinate]

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Contribution guide.

🔴 Required Information

Is your feature request related to a specific problem?

When ADK workflows delegate tasks to sub-agents, agents lack a standard mechanism to verify if a target agent URI (agent://<namespace>/<name>) is cryptographically signed before executing tasks. This allows untrusted agent calls and unverified prompt injections to compromise multi-agent execution loops.

Describe the Solution You'd Like

Introduce CreduentGoogleADKPlugin — a local Ed25519 + JCS RFC 8785 cryptographic verification plugin for agent URIs in under 5ms, with no network calls required.

Impact on your work

Critical for securing enterprise multi-agent delegation chains. Implementation and test suite are ready to submit as a Pull Request.

Willingness to contribute

Yes

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🟡 Recommended Information

Describe Alternatives You've Considered

1. Manual HTTP verification before sub-agent calls — adds latency.
2. Custom wrapper functions — no standard schema validation across frameworks.

Proposed API / Implementation

from creduent.integrations.google_adk import CreduentGoogleADKPlugin

plugin = CreduentGoogleADKPlugin(
    agent_uri="agent://assistant.dev/agent",
    timeout=10
)

Additional Context

• Python SDK: pip install creduent / pip install google-adk
• Open-Source Protocol: https://github.com/idevsec/creduent