**Why use a blockchain if prompts are signed locally?** - S…

**Why use a blockchain if prompts are signed locally?**
- Shared root of trust: The contract is the public, tamper‑resistant source of truth for “who is allowed to direct this agent and for what scopes.” Anyone (tools, other agents, verifiers) can independently check it.
- Revocation and rotation: Keys/sessions can be revoked/rotated on-chain once, and every verifier (including the agent itself and external tools) immediately has the same answer without trusting your local config.
- Capability discovery: Tools the agent calls can gate their own actions by querying the same on-chain policy (defense‑in‑depth). That only works if the policy is globally accessible and authenticated.
- Auditability/attestation: You can optionally anchor hashes of accepted prompts/executions on-chain for third‑party verification later.
- Interop: Multiple agents, UIs, and services can coordinate around one canonical policy without bespoke integrations.