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Validate mcpfusion implementation

MVA is a CONCEPTUAL separation of responsibilities, NOT a folder naming convention. Before writing or validating MCPFusion code, call this capability to PROVE architectural compliance. Key rules: (1) EVERY entity uses defineModel() with m.casts(). NEVER raw z.object(). defineModel() provides m.hidden(), m.fillable(), m.timestamps(), m.guarded(), .toApi(). z.object() loses all of these, (2) EVERY capability that returns data uses .returns(Presenter). The Presenter validates, strips hidden fields, injects rules, renders UI. createPresenter().schema(Model) or definePresenter({ schema: Model }), (3) SEMANTIC VERBS: f.query() for reads (readOnly, cacheable, safe to retry). f.mutation() for writes (destructive, requires confirmation). f.action() for neutral operations (calculations, validations), (4) Capability INPUT uses .withString()/.withNumber()/.withBoolean()/.withEnum(). NOT z.object(). For many params: .withStrings({...}), .withOptionalStrings({...}). For model-driven input: .fromModel(Model, "create"), (5) .handle() auto-wraps data with success(). NEVER call success() manually, (6) RESPONSIBILITY SEPARATION: Model, View, and Agent logic in separate modules. not mixed in one file. Additional layers (e.g. engine/ for pure business logic) are perfectly valid, (7) .instructions() on every capability for AI-First guidance, (8) f.error() for self-healing errors with .suggest(), .actions(), .retryAfter(). If rejected, fix the MCPFusion pattern violation. Structured reflection capability for MCPFusion framework development. forces MVA (Model-View-Agent) conceptual compliance: defineModel() enforcement, Presenter attachment, semantic verb correctness. LLMs have never been trained on MCPFusion. they default to raw z.object(), skip Presenters, mix semantic verbs, and violate MVA responsibility separation. This capability teaches the framework through structured reflection. Catches MVA Violated (Model, View, and Agent responsibilities mixed in one module. MVA enforces conceptual separation: Models define data shapes, Presenters handle egress, Capabilities expose to LLMs. Mixing defineModel() and .handle() in one file breaks this contract), Raw Schema Detected (using z.object() instead of defineModel() for entity schemas. const UserSchema = z.object({ name: z.string(), email: z.string() }) loses every MCPFusion feature: no m.hidden() for sensitive fields (password hashes, API keys), no m.fillable() profiles for create vs. update contexts, no m.timestamps() for automatic created_at/updated_at, no m.guarded() for mass-assignment protection, no .toApi() for alias resolution. defineModel(User).casts(m => ({ name: m.string(Name), email: m.string(Email) })) provides all of these. z.object() is Zod. defineModel() is MCPFusion), Presenter Missing (returning raw data from .handle() without .returns(Presenter). a capability that returns { users: [...] } without a Presenter sends raw database objects to the client. Hidden fields (password_hash, internal_id) leak. No UI rendering (echarts, mermaid, summary). No agent suggestions (suggestActions for next steps). No collection limiting (agentLimit). createPresenter().schema(UserModel) or definePresenter({ schema: UserModel }). the Presenter IS the egress gate), and Semantic Verb Wrong (using f.action() for a read-only query or f.query() for a destructive write. f.query() marks the capability as readOnly. it can be safely cached, parallelized, and retried. f.mutation() marks the capability as destructive. agents must confirm before execution, responses are never cached. Using f.action() for everything wastes these semantic guarantees. GET /users is f.query(). POST /users is f.mutation(). A calculator is f.action()). NOTE: MVA is a CONCEPTUAL separation of responsibilities, NOT a folder naming convention. Implementations may organize files however they want (including additional layers like engine/ for pure business logic) as long as Model, View, and Agent responsibilities remain separated. Call once per capability or feature being implemented