# Target broad app-server compatibility

Target Codex CLI, IDE, desktop, mobile Remote, and third-party app-server clients. Treat every stable and experimental JSON-RPC method implemented by the referenced `openai/codex` App Server as part of the compatibility contract rather than limiting the contract to methods observed from one client. Map methods onto Pi capabilities when equivalents exist and onto project-owned metadata when the adapter can reproduce the behavior. Otherwise, keep Pi's agent implementation unchanged and return schema-valid neutral or mock values; safe Codex-only settings are accepted without enforcement. Missing Pi behavior must not surface as JSON-RPC `Method not found`. The adapter may return an explicit error only when no schema-valid response can avoid falsely claiming a consequential external side effect or security guarantee.