json-render/packages/core/CHANGELOG.md

@json-render/core

0.6.1

Patch Changes

• ea97aff: Fix infinite re-render loop caused by multiple unbound form inputs (Input, Textarea, Select) all registering field validation at the same empty path with different checks configs, causing them to overwrite each other endlessly. Stabilize context values in ActionProvider, ValidationProvider, and useUIStream by using refs for state/callbacks, preventing unnecessary re-render cascades on every state update.

0.6.0

Minor Changes

• 06b8745: Chat mode (inline GenUI), AI SDK integration, two-way binding, and expression-based visibility/props.

### New: Chat Mode (Inline GenUI)

Two generation modes: Generate (JSONL-only, the default) and Chat (text + JSONL inline). Chat mode lets AI respond conversationally with embedded UI specs — ideal for chatbots and copilot experiences.

• catalog.prompt({ mode: "chat" }) generates a chat-aware system prompt
• pipeJsonRender() server-side transform separates text from JSONL patches in a mixed stream
• createJsonRenderTransform() low-level TransformStream for custom pipelines

### New: AI SDK Integration

First-class Vercel AI SDK support with typed data parts and stream utilities.

• SpecDataPart type for data-spec stream parts (patch, flat, nested payloads)
• SPEC_DATA_PART / SPEC_DATA_PART_TYPE constants for type-safe part filtering
• createMixedStreamParser() for parsing mixed text + JSONL streams

### New: React Chat Hooks

• useChatUI() — full chat hook with message history, streaming, and spec extraction
• useJsonRenderMessage() — extract spec + text from a message's parts array
• buildSpecFromParts() / getTextFromParts() — utilities for working with AI SDK message parts
• useBoundProp() — two-way binding hook for $bindState / $bindItem expressions

### New: Two-Way Binding

Props can now use $bindState and $bindItem expressions for two-way data binding. The renderer resolves bindings and passes a bindings map to components, enabling write-back to state.

### New: Expression-Based Props and Visibility

Replaced string token rewriting with structured expression objects:

• Props: { $state: "/path" }, { $item: "field" }, { $index: true }
• Visibility: { $state: "/path", eq: "value" }, { $item: "active" }, { $index: true, gt: 0 }
• Logic: { $and: [...] }, { $or: [...] }, and implicit AND via arrays
• Comparison operators: eq, neq, gt, gte, lt, lte, not

### New: Utilities

• applySpecPatch() — typed convenience wrapper for applying a single patch to a Spec
• nestedToFlat() — convert nested tree specs to flat { root, elements } format
• resolveBindings() / resolveActionParam() — resolve binding paths and action params

### New: Chat Example

Full-featured chat example (examples/chat) with AI agent, tool calls (crypto, GitHub, Hacker News, weather, search), theme toggle, and streaming UI generation.

### Improved: Renderer

• ElementRenderer is now React.memo'd for better performance in repeat lists
• emit is always defined (never undefined) — no more optional chaining needed
• Action params are resolved through resolveActionParam supporting $item, $index, $state
• Repeat scope now passes the actual item object instead of requiring token rewriting

### Breaking Changes

• Expressions renamed: { $path } / { path } replaced by { $state }, { $item }, { $index }
• Visibility conditions: { path } → { $state }, { and/or/not } → { $and/$or } with not as operator flag
• DynamicValue: { path: string } → { $state: string }
• Repeat field: repeat.path → repeat.statePath
• Action params: path → statePath in setState action params
• Provider props: actionHandlers → handlers on JSONUIProvider/ActionProvider
• Auth removed: AuthState type and { auth } visibility conditions removed — model auth as regular state
• Legacy catalog removed: createCatalog, generateCatalogPrompt, generateSystemPrompt, ComponentDefinition, CatalogConfig, SystemPromptOptions removed
• React exports removed: createRendererFromCatalog, rewriteRepeatTokens
• Codegen: traverseTree → traverseSpec, SpecVisitor → TreeVisitor

0.5.2

Patch Changes

• 429e456: Fix LLM hallucinations by dynamically generating prompt examples from the user's catalog instead of hardcoding component names. Adds optional example field to ComponentDefinition with Zod schema introspection fallback. Mentions RFC 6902 in output format section.

0.5.1

0.5.0

Minor Changes

• 3d2d1ad: Add @json-render/react-native package, event system (emit replaces onAction), repeat/list rendering, user prompt builder, spec validation, and rename DataProvider to StateProvider.

0.4.4

Patch Changes

• dd17549: remove key/parentKey from flat specs, RFC 6902 compliance for SpecStream

0.4.3

Patch Changes

• 61ee8e5: include remove op in system prompt

0.4.2

Patch Changes

• 54bce09: add defineRegistry function