Implement deterministic pre-action authorization at the `before_tool_call` hook level, as per the Open Agent Protocol (OAP), to enforce declarative policies (agent identity, capability boundaries, rate limits) and prevent silent injection risks.
### Is your feature request related to a problem? Please describe. VoltAgent's guardrail system validates content but doesn't deterministically authorize tool execution before it happens. With MCP servers proliferating, agents face silent injection risks where a poisoned prompt triggers unintended tool calls. The Open Agent Protocol (OAP) provides a before_tool_call hook that checks every execution against a declarative policy - agent identity, capability boundaries, and rate limits enforced at the framework level, not prompt level. Given VoltAgent's existing lifecycle hooks and Zod-typed tools, adding OAP support would be a minimal wrapper that unlocks enterprise security compliance. Reference implementation: https://github.com/aporthq/aport-agent-guardrails - DOI: [10.5281/zenodo.18901596](https://doi.org/10.5281/zenodo.18901595) ### Describe alternatives you've considered _No response_ ### Additional context _No response_ ### Describe the thing to improve Provide an option