--- title: Interfaces and Core description: How Ennodia's Model Context Protocol (MCP) interface and shared core behavior relate to each other. --- ## Current shape Ennodia has a Model Context Protocol (MCP) interface and a shared Core. | Name | Status | What it means | | --- | --- | --- | | Ennodia MCP | Available | The shipped MCP tool interface for agents. Use this today. | | Ennodia Core | Available | Shared orchestration behavior behind the MCP and IO surfaces. | ## Ennodia MCP Ennodia MCP is the supported public surface in the current release. It exposes tools such as `ennodia_list_harnesses`, `ennodia_estimate_budget`, `ennodia_run`, `ennodia_start_plan_advice`, `ennodia_get_run`, and `ennodia_start_compare`. Each tool is a schema plus one Core call — nothing more. Use MCP when a primary agent needs help from installed local agent command-line interface (CLI) programs. ## Ennodia Core Core is responsible for: - discovering supported local harnesses - planning routes with caller-provided categories or keyword fallback - estimating preflight budgets and enforcing local caps on that estimate - running the optional Plan Advisor against a bounded inventory, validating its inert proposal, and requiring a separate digest-bound call before execution - starting child tasks through thin adapters - capturing status, output, failures, and timing - resolving compositional slices and reporting Compare readiness - running the Judge and Result Advisor over successful outputs when Compare is requested The roles do not own runtime policy. Plan Advisor proposes harness, model, and skill assignments but never executes them. Result Advisor combines Judge findings after Compare. If Judge analysis is unavailable, its candidates-only basis is exposed rather than hidden. ## Ennodia IO Ennodia IO is a local app interface. Start the Hypertext Transfer Protocol (HTTP) server with: ```sh npx -y @cherninlab/ennodia-io ``` See [Ennodia IO](/docs/reference/ennodia-io/) for supported fields, rejected features, local binding defaults, and auth behavior.