Reputation & Trust Signals
How audit logs and agent activity feed into scoring, risk assessment, and policy enforcement
Reputation & Trust Signals
Key Takeaways
- Reputation scoring allows dynamic enforcement based on agent behavior - Trust signals can be derived from audit logs, revocation events, and verifier outcomes - Scoring models range from boolean allowlists to continuous trust scores - Verifiers can enforce risk-based policy at request time using reputation
Why Reputation Matters
In autonomous systems, the identity of an agent isn't enough. Reputation allows services to assess how trustworthy an agent is, based on its behavior over time.
Overview
MCP-I supports a pluggable trust scoring model based on:
- Audit events emitted by agents or services
- Delegation chain evaluation
- Revocation history
- Optional external scoring registries (e.g., knowthat.ai)
This allows a verifier or relying party to adapt access controls, rate limits, or challenge levels dynamically.
Trust Signals
Example signal categories:
| Signal Type | Description |
|---|---|
| Successful delegation | How often a user successfully delegates to this agent |
| Failed verification | Frequency of VC or chain rejections |
| Revocation impact | Has the agent’s credentials been revoked often? |
| Audit density | Activity volume and frequency |
| Block/allow flags | Registry-based signals (manual or computed) |
Scoring Models
Scoring can be as simple or as complex as needed:
- Boolean allow/deny (e.g.,
agent.isBlacklisted = true) - Weighted metrics (e.g.,
trustScore = 0.82) - External models (e.g., machine learning inference on log streams)
Each verifier can be configured with local or shared scoring strategies.
Trust Reaction Policies
Verification and access enforcement can change based on trust score:
| Score Range | Verifier Behavior |
|---|---|
| 0.9–1.0 | Fast path / cacheable access |
| 0.6–0.89 | Standard checks enforced |
| < 0.6 | Challenge or MFA required |
| 0.0 | Blocked (deny) |
Integration Points
Reputation scoring pulls from logs generated by:
Scores can be:
- Stored locally
- Synced with a global registry
- Embedded in delegation metadata or verifier headers
Knowthat.ai Registry
KYA-powered deployments may optionally sync trust signals to a global registry at knowthat.ai, which supports:
- Agent lookup by DID
- Federation-safe trust flagging
- Shared deny/allow lists
This is optional and not required by the MCP-I spec.
Next Steps
→ Learn how audit logs are generated in Audit Layer
→ See how verifiers use trust signals in Edge Verification Guide