Give provider streams one lifecycle owner (Gates 1-4)

CONTEXT.md

@@ -14,3 +14,22 @@ reasons as completed steps, and mapping thrown errors to known terminal
 provider errors. The agent **runtime** layer starts streams and the **hosted**
 layer finishes them; both consult this module rather than re-deriving the
 interpretation, so provider behavior changes land in one file.
+
+## Stream Lifecycle
+
+The single owner of one provider stream attempt, from the first provider read
+until completion, tool handoff, cancellation, or failure:
+`src/agent/streaming/lifecycle/`. It decodes provider parts through a Provider
+Adapter, reduces them into validated **semantic**, **telemetry**, and
+**diagnostic** frames, owns monotonic provider-wait deadlines and status
+cadence, and settles exactly one typed Stream Outcome per attempt. Telemetry
+observes execution but never extends a semantic deadline. One agent run may
+contain several provider attempts separated by local tool execution.
+
+## Stream Delivery
+
+The separate agent-loop fan-out boundary that will route lifecycle frames to
+live, durable, diagnostic, and usage Adapters (Phase 5, separately designed).
+Through Gate 4, hosted durable and AG-UI production projections still consume
+compatibility UI chunks, and production runs stay on stream protocol
+version 1.

docs/api-reference/index.md

@@ -32,6 +32,7 @@ order: 1
 | [`veryfront/observability`](./veryfront/observability.md) | Tracing, metrics, errors, and logs. |
 | [`veryfront/prompt`](./veryfront/prompt.md) | MCP prompt definitions. |
 | [`veryfront/provider`](./veryfront/provider.md) | Model provider registry. |
+| [`veryfront/release-assets`](./veryfront/release-assets.md) | Release Asset Manifest - public barrel. |
 | [`veryfront/resource`](./veryfront/resource.md) | MCP resource definitions. |
 | [`veryfront/router`](./veryfront/router.md) | Client navigation and route context. |
 | [`veryfront/runs`](./veryfront/runs.md) | Canonical durable task and workflow runs. |

docs/api-reference/veryfront/chat.md

@@ -168,8 +168,8 @@ Result returned from use agent.
 | `ConversationScrollButton` | Render conversation scroll button. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/components/empty-state.tsx#L116) |
 | `ConversationsProvider` | ConversationsProvider - calls `useConversations` once with your `store` / `id` / `onSelect` and shares it via `ConversationsContext`. Declare persistence + router wiring here, once, at the app layout; children read it with `useConversationsContext`. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/contexts/conversations-context.tsx#L45) |
 | `CopyButton` |  | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/ui/code-block.tsx#L334) |
-| `DEFAULT_CHAT_STREAM_IDLE_TIMEOUT_MS` | Default value for chat stream idle timeout ms. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L4) |
-| `DEFAULT_CHAT_STREAM_TOOL_RUNNING_TIMEOUT_MS` | Default value for chat stream tool running timeout ms. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L6) |
+| `DEFAULT_CHAT_STREAM_IDLE_TIMEOUT_MS` | Default value for chat stream idle timeout ms. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L6) |
+| `DEFAULT_CHAT_STREAM_TOOL_RUNNING_TIMEOUT_MS` | Default value for chat stream tool running timeout ms. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L8) |
 | `DropZoneOverlay` | Drag overlay shown over the composer while files are dragged onto it - the glyph-in-a-circle + "Drop files" from Studio's `PromptForm`. Rendered inside a `relative` card; fills it and blurs the content behind. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/components/drop-zone.tsx#L18) |
 | `ErrorBanner` | Render error banner. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/composition/error-banner.tsx#L28) |
 | `FadeIn` | Render fade in. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/components/animations.tsx#L37) |
@@ -206,19 +206,19 @@ Result returned from use agent.
 |------|-------------|--------|
 | `agentsToPickerOptions` | Narrow browser-safe agent metadata to the picker's row shape. `AgentOption` now shares `AgentMetadata`'s `avatarUrl` field, so `AgentMetadata[]` is also accepted by `<AgentPicker agents>` directly - this helper just drops the fields the rows don't use. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat-agent-picker.tsx#L32) |
 | `buildChatStreamChunkMessageMetadata` | Builds chat stream chunk message metadata. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/chat-ui-message-helpers.ts#L233) |
-| `createChatStreamWatchdog` | Create chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L167) |
-| `createChatStreamWatchdogState` | State for create chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L50) |
+| `createChatStreamWatchdog` | Create chat stream watchdog backed by the lifecycle deadline primitive. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L267) |
+| `createChatStreamWatchdogState` | State for create chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L54) |
 | `dedupeChatUiMessageChunks` | Dedupe chat UI message chunks. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/chat-ui-message-helpers.ts#L288) |
 | `downloadMarkdown` | Download messages as a .md file. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/export.ts#L64) |
 | `exportAsMarkdown` | Convert chat messages to a markdown string. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/export.ts#L12) |
 | `extractChatMessageMetadata` | Extract chat message metadata. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/chat-ui-message-helpers.ts#L227) |
 | `extractSourcesFromParts` | Extract sources from native citations and tool result parts. Native source parts map directly, while tool outputs may expose a `documents` array. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L164) |
 | `getAgentPromptSuggestions` | Return prompt text suggestions that the current Chat component can render. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/react/use-agent-metadata.ts#L161) |
-| `getNextChatStreamWatchdogState` | State for get next chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L84) |
+| `getNextChatStreamWatchdogState` | State for get next chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L95) |
 | `getTextContent` | Get text content from chat message parts | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L16) |
 | `groupPartsInOrder` | Group consecutive parts for ordered rendering Returns an array of groups, each containing either consecutive text parts, a tool part, or a reasoning part | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L102) |
-| `isHeartbeatOnlyMetadataChunk` | Check whether a chunk only carries heartbeat metadata. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L162) |
-| `isLongRunningToolRunning` | Check whether a long-running tool is active. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L70) |
+| `isHeartbeatOnlyMetadataChunk` | Check whether a chunk only carries heartbeat metadata. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L185) |
+| `isLongRunningToolRunning` | Compatibility helper. Long-running tool names no longer disable the absolute tool-running deadline; this predicate remains exported for callers that classify tool activity. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L81) |
 | `isReasoningPart` | Check if a part is a reasoning part | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L82) |
 | `isSkillToolPart` | Check if a tool part is a skill-related tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L77) |
 | `isToolPart` | Check if a part is a tool part | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/utils/message-parts.ts#L32) |
@@ -258,7 +258,7 @@ Result returned from use agent.
 | Name | Description | Source |
 |------|-------------|--------|
 | `ChatErrorBoundary` | Implement chat error boundary. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/error-boundary.tsx#L17) |
-| `ChatStreamIdleTimeoutError` | Error shape for chat stream idle timeout. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L34) |
+| `ChatStreamIdleTimeoutError` | Error shape for chat stream idle timeout. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L36) |
 
 ### Types
 
@@ -345,17 +345,17 @@ Result returned from use agent.
 | `ChatSidebarRootProps` | Props accepted by `ChatSidebarRoot`. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/components/sidebar.tsx#L205) |
 | `ChatStepPart` | Public API contract for chat step part. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L100) |
 | `ChatStreamEvent` | Event emitted for chat stream. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L217) |
-| `ChatStreamWatchdogOptions` | Options accepted by chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L24) |
-| `ChatStreamWatchdogPhase` | Public API contract for chat stream watchdog phase. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L9) |
-| `ChatStreamWatchdogState` | State for chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/stream-watchdog.ts#L16) |
+| `ChatStreamWatchdogOptions` | Options accepted by chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L26) |
+| `ChatStreamWatchdogPhase` | Public API contract for chat stream watchdog phase. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L11) |
+| `ChatStreamWatchdogState` | State for chat stream watchdog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/agent/streaming/lifecycle/watchdog-compat-adapter.ts#L18) |
 | `ChatTab` | Public API contract for chat tab. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat/components/tab-switcher.tsx#L13) |
 | `ChatTextPart` | Chat message part that carries text. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L11) |
 | `ChatTheme` | Public API contract for chat theme. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/theme.ts#L22) |
 | `ChatThemeScopeProps` | Props accepted by `ChatThemeScope`. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/react/components/chat/chat-theme-scope.tsx#L23) |
 | `ChatToolPart` | Public API contract for chat tool part. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L65) |
 | `ChatToolResultPart` | Chat message part that carries a tool result. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L78) |
 | `ChatToolState` | State for chat tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L57) |
-| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L407) |
+| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L408) |
 | `ChildRunAudit` | Public API contract for child run audit. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L159) |
 | `ChildRunAuditToolCall` | Public API contract for child run audit tool call. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L144) |
 | `ChildRunAuditToolResult` | Result returned from child run audit tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L151) |
@@ -600,7 +600,7 @@ import "veryfront/chat/protocol";
 | `ChatToolPart` | Public API contract for chat tool part. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L65) |
 | `ChatToolResultPart` | Chat message part that carries a tool result. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L78) |
 | `ChatToolState` | State for chat tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L57) |
-| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L407) |
+| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L408) |
 | `ChildRunAudit` | Public API contract for child run audit. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L159) |
 | `ChildRunAuditToolCall` | Public API contract for child run audit tool call. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L144) |
 | `ChildRunAuditToolResult` | Result returned from child run audit tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L151) |
@@ -650,7 +650,7 @@ import { buildDataFileAnnotation, isImageFile, isTextPreviewFile } from "veryfro
 | `ChatToolResultOutput` | Output from chat tool result. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L224) |
 | `ChatToolResultPart` | Provider model message part that carries a tool result. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L239) |
 | `ChatUiMessage` | Message shape for chat UI. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L179) |
-| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L407) |
+| `ChatUiMessageChunk` | Public API contract for chat UI message chunk. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/protocol.ts#L408) |
 | `ChatUiMessagePart` | Public API contract for chat UI message part. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L167) |
 | `ChatUiMessageRole` | Public API contract for chat UI message role. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L68) |
 | `ChatUserContentPart` | Public API contract for chat user content part. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/chat/types.ts#L248) |

docs/api-reference/veryfront/index.client.md

@@ -34,7 +34,7 @@ export function GET() {
 | Name | Description | Source |
 |------|-------------|--------|
 | `CommonSchemas` | Lazy-getter object that preserves the `CommonSchemas.email` call shape. Each access returns the cached `Schema<T>` (memoized inside `defineSchema`), so chained calls like `CommonSchemas.email.parse(x)` work as before. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/schemas/common.ts#L65) |
-| `INPUT_VALIDATION_FAILED` | HTTP request input validation failures (replaces ValidationError) | [source](https://github.com/veryfront/veryfront-code/blob/main/src/errors/error-registry/general.ts#L77) |
+| `INPUT_VALIDATION_FAILED` | HTTP request input validation failures (replaces ValidationError) | [source](https://github.com/veryfront/veryfront-code/blob/main/src/errors/error-registry/general.ts#L86) |
 
 ### Functions
 
@@ -75,10 +75,10 @@ export function GET() {
 | `MDXFrontmatter` | Parsed frontmatter values from an MDX page. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/types/index.ts#L89) |
 | `PageContext` | Runtime page context passed to page components. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/types/index.ts#L106) |
 | `PageWithData` | Page with data fetching capabilities | [source](https://github.com/veryfront/veryfront-code/blob/main/src/data/types.ts#L16) |
-| `StartServerOptions` | Server options. Defaults to development mode with HMR. Set `mode: "production"` for a production server. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L129) |
+| `StartServerOptions` | Server options. Defaults to development mode with HMR. Set `mode: "production"` for a production server. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L130) |
 | `StaticPathsResult` | Return type for `getStaticPaths()`. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/data/schemas/data.schema.ts#L61) |
 | `ValidatedHandlerConfig` | Configuration for `createValidatedHandler()`. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/security/input-validation/handler.ts#L7) |
 | `ValidatedHandlerFunction` | Handler signature that receives validated request data. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/security/input-validation/handler.ts#L14) |
 | `VeryfrontConfig` | Project configuration. The underlying zod schema stores `extensions` as `unknown[]`; this tightened alias surfaces the expected `ExtensionConfigEntry[]` shape to TypeScript consumers. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/config/schemas/index.ts#L25) |
-| `VeryfrontHandler` | Web API request handler with WebSocket upgrade and HMR helpers. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L144) |
-| `VeryfrontServer` | Running server instance with lifecycle controls. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L132) |
+| `VeryfrontHandler` | Web API request handler with WebSocket upgrade and HMR helpers. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L145) |
+| `VeryfrontServer` | Running server instance with lifecycle controls. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/server/index.ts#L133) |