Align AI chat protocol with Vercel AI SDK — remove custom types and schemas by Copilot · Pull Request #1028 · objectstack-ai/objectstack

Copilot · 2026-04-01T01:57:29Z

The spec layer defined custom AI chat types (AIMessage, AIToolCall, AIStreamEvent) and Zod schemas (AiChatRequestSchema, AiChatResponseSchema) that duplicate what the Vercel AI SDK already provides. Since the frontend uses @ai-sdk/react/useChat directly, these custom definitions create maintenance burden and potential drift.

Re-export Vercel AI SDK types as canonical

ModelMessage replaces AIMessage
ToolCallPart replaces AIToolCall
ToolResultPart replaces AIToolResult
TextStreamPart<ToolSet> replaces AIStreamEvent
Deprecated type aliases preserved for downstream migration

// Beforeimporttype{AIMessage,AIStreamEvent}from'@objectstack/spec/contracts';// Afterimporttype{ModelMessage,TextStreamPart,ToolSet}from'ai';// or use deprecated aliases during migration:importtype{AIMessage}from'@objectstack/spec/contracts';// = ModelMessage

Update service contracts

IAIService.chat(), streamChat(), chatWithTools() now accept ModelMessage[]
LLMAdapter methods updated similarly
AIConversation.messages is now ModelMessage[]
ChatWithToolsOptions.onToolError callback receives ToolCallPart

Remove redundant chat wire protocol

Removed AiChatRequestSchema / AiChatResponseSchema from protocol.zod.ts
Removed aiChat from IObjectStackAPI, DEFAULT_AI_ROUTES, and client SDK
NLQ, Suggest, Insights schemas retained (ObjectStack-specific)

Migrate `packages/services/service-ai` to canonical Vercel types

All 8 source files and 4 test files in service-ai have been migrated from deprecated aliases to canonical Vercel AI SDK types with proper structural alignment:

ToolRegistry: execute() now accepts ToolCallPart (using toolCallId, toolName, input) and returns ToolExecutionResult (extends ToolResultPart with isError?: boolean for error tracking in the tool-call loop)
AIService.chatWithTools(): Constructs proper AssistantModelMessage (content as Array<TextPart | ToolCallPart>) and ToolModelMessage (content as Array<ToolResultPart>)
MemoryLLMAdapter.streamChat(): Emits Vercel TextStreamPart<ToolSet> events with { type: 'text-delta', id, text } format
Conversation services: Serialize/deserialize ModelMessage discriminated union to/from flat DB columns with backward compatibility for old-format messages
Stream helpers: textDeltaPart() and finishPart() utility functions eliminate repeated type casts
All 158 service-ai tests updated and passing

Fix documentation

Removed AiChatRequest / AiChatResponse references from content/docs/references/api/protocol.mdx

vercel · 2026-04-01T01:57:34Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
objectstack-play	Ready	Preview, Comment	Apr 1, 2026 5:02am
spec	Ready	Preview, Comment	Apr 1, 2026 5:02am

Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/2515d700-01d1-4303-8678-41f0ce9674da Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

…and schemas - Re-export ModelMessage, ToolCallPart, ToolResultPart, TextStreamPart from 'ai' - Remove AiChatRequestSchema/AiChatResponseSchema (use Vercel wire protocol) - Update IAIService/LLMAdapter to use Vercel types - Deprecate AIMessage, AIToolCall, AIToolResult, AIStreamEvent as aliases - Remove aiChat from IObjectStackAPI, client SDK, and DEFAULT_AI_ROUTES - Keep NLQ/Suggest/Insights protocols (ObjectStack-specific) - Update all tests (6772 pass) - Update CHANGELOG.md and ROADMAP.md Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/2515d700-01d1-4303-8678-41f0ce9674da Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

hotlong · 2026-04-01T02:57:54Z

@copilot 评估是否已经完成了任务中要求的所有开发，继续

hotlong · 2026-04-01T04:22:33Z

@copilot 继续

…AI SDK types - toolCalls: {id, name, arguments} → {type, toolCallId, toolName, input} - AIMessage → ModelMessage - AIStreamEvent → TextStreamPart<ToolSet> - AIToolCall → ToolCallPart - textDelta → text - toolCall?.name → toolName - streamChat yields updated to Vercel AI SDK format - onToolError assertions: name → toolName Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

… types - AIMessage → ModelMessage - AIToolCall → ToolCallPart - Tool call objects: { id, name, arguments } → { type: 'tool-call', toolCallId, toolName, input } - Tool result access: result.content → (result.output as any).value - Assistant message assertions: .toolCalls → content-based ToolCallPart filtering - Tool message assertions: .toolCallId/.content → content[0].toolCallId/.output.value Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

- Update objectql-conversation-service.test.ts to use ModelMessage - Export ToolExecutionResult from tools/index.ts and service index - Fix comment referencing AIMessage in ai-routes.ts Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

- Extract extractOutputText() helper to deduplicate error text extraction - Replace any casts with proper type guards in objectql-conversation-service Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/7b5017d9-7b75-41e6-a0ad-6eb250b8d770 Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

…narrowing Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/7b5017d9-7b75-41e6-a0ad-6eb250b8d770 Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Copilot · 2026-04-01T04:58:04Z

@copilot 继续

All remaining work is now complete in commit bcf879f:

service-ai fully migrated — All 8 source files and 4 test files now use canonical Vercel AI SDK types (ModelMessage, ToolCallPart, ToolResultPart, TextStreamPart<ToolSet>). Zero references to deprecated aliases remain. All 158 tests pass.
Documentation fixed — Removed AiChatRequest/AiChatResponse references from protocol.mdx.
Code review feedback addressed — Extracted textDeltaPart()/finishPart() helpers, improved type narrowing in tests, removed redundant Array.isArray() checks.

Copilot

Pull request overview

This PR aligns ObjectStack’s AI chat contracts and related runtime/service code with the canonical Vercel AI SDK (ai) message/tool/streaming types, removing the duplicated “AiChat” wire protocol and migrating downstream usage to Vercel’s discriminated unions.

Changes:

Re-export Vercel AI SDK types in @objectstack/spec/contracts and update IAIService / LLMAdapter signatures to use ModelMessage[] and TextStreamPart<ToolSet>.
Remove AiChatRequestSchema / AiChatResponseSchema and the aiChat method/route/client surface area from the ObjectStack protocol layer.
Migrate @objectstack/service-ai tool calling, conversation persistence, and streaming helpers to Vercel AI SDK message/part shapes.

Reviewed changes

Copilot reviewed 27 out of 28 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
ROADMAP.md	Bumps “Last Updated” date to reflect protocol changes.
pnpm-lock.yaml	Locks new `ai` dependency and its transitive packages.
packages/spec/src/contracts/llm-adapter.ts	Switches adapter contract to Vercel `ModelMessage` + `TextStreamPart<ToolSet>`.
packages/spec/src/contracts/llm-adapter.test.ts	Updates contract tests to compile against Vercel stream/message types.
packages/spec/src/contracts/ai-service.ts	Re-exports canonical Vercel types; preserves deprecated aliases; updates service contracts.
packages/spec/src/contracts/ai-service.test.ts	Updates contract tests for Vercel message/stream/tool-part shapes.
packages/spec/src/api/protocol.zod.ts	Removes AiChat request/response schemas and `aiChat` from protocol interface.
packages/spec/src/api/protocol.test.ts	Removes AiChat schema validation assertions.
packages/spec/src/api/plugin-rest-api.zod.ts	Removes `aiChat` from default AI REST route registration.
packages/spec/src/api/plugin-rest-api.test.ts	Updates expectations for removed `aiChat` endpoint.
packages/spec/package.json	Adds `ai` dependency to spec for type re-exports.
packages/services/service-ai/src/tools/tool-registry.ts	Migrates tool execution to `ToolCallPart` input + `ToolResultPart` output (`ToolExecutionResult`).
packages/services/service-ai/src/tools/index.ts	Exports `ToolExecutionResult` type.
packages/services/service-ai/src/routes/ai-routes.ts	Updates route typing/casts to `ModelMessage`.
packages/services/service-ai/src/routes/agent-routes.ts	Updates agent chat route message typing to `ModelMessage`.
packages/services/service-ai/src/index.ts	Re-exports new tool execution result type.
packages/services/service-ai/src/conversation/objectql-conversation-service.ts	Serializes/deserializes Vercel `ModelMessage` union into flat DB columns.
packages/services/service-ai/src/conversation/in-memory-conversation-service.ts	Updates conversation message type to `ModelMessage`.
packages/services/service-ai/src/ai-service.ts	Migrates chat/tool-call loop + streaming helpers to Vercel message/stream part formats.
packages/services/service-ai/src/agent-runtime.ts	Updates system message construction to `ModelMessage`.
packages/services/service-ai/src/adapters/memory-adapter.ts	Streams Vercel `TextStreamPart<ToolSet>` and handles non-string message content safely.
packages/services/service-ai/src/tests/objectql-conversation-service.test.ts	Updates persistence tests for Vercel message union shapes.
packages/services/service-ai/src/tests/chatbot-features.test.ts	Updates tool-calling tests to Vercel tool-call/tool-result parts.
packages/services/service-ai/src/tests/auth-and-toolcalling.test.ts	Updates streaming/tool-loop tests to Vercel stream parts + tool call parts.
packages/services/service-ai/src/tests/ai-service.test.ts	Updates AIService + ToolRegistry tests to new types and stream part fields.
packages/client/src/index.ts	Removes client `ai.chat()` method and associated exported types.
content/docs/references/api/protocol.mdx	Removes AiChat protocol docs and references in TypeScript usage snippet.
CHANGELOG.md	Documents the migration/removal and new `ai` dependency.

Files not reviewed (1)

pnpm-lock.yaml: Language not supported

Copilot · 2026-04-01T05:07:38Z

 /**
- * Validate that `raw` is a well-formed AIMessage.
+ * Validate that `raw` is a well-formed message.
 * Returns null on success, or an error string on failure.
 */
 function validateMessage(raw: unknown): string | null {


validateMessage() is still written for the old flat message shape (it assumes content is always a string). With the switch to Vercel ModelMessage, assistant.content can be an array of parts (including tool-call parts) and tool.content is an array of tool-result parts, so this validator will reject valid tool-calling conversations and/or force unsafe casts downstream. Please update validation to be role-aware (system/user: string; assistant: string | parts[]; tool: tool-result parts[]) or validate against Vercel AI SDK message structures before invoking aiService/conversationService.

Copilot · 2026-04-01T05:07:39Z

+ "ai": "^6.0.142",
 "zod": "^4.3.6"
 },


Adding ai as a direct dependency pulls in transitive packages with stricter Node engine requirements (e.g. @vercel/oidc declares node >= 20 in the lockfile). This is inconsistent with the repo/package engines (node >=18) and can break installs in engine-strict environments or cause runtime incompatibilities. Consider (a) verifying the project’s supported Node version and bumping engines.node accordingly, or (b) switching to an ai version whose transitive deps support Node 18, or (c) moving ai to a peer dependency (with clear install guidance) since it’s only needed for type re-exports.
Suggested change
"ai": "^6.0.142",
"zod": "^4.3.6"
},
"zod": "^4.3.6"
},
"peerDependencies": {
"ai": "^6.0.142"
},

Copilot · 2026-04-01T05:07:39Z

+ '@vercel/oidc@3.1.0':
+ resolution: {integrity: sha512-Fw28YZpRnA3cAHHDlkt7xQHiJ0fcL+NRcIqsocZQUSmbzeIKRpwttJjik5ZGanXP+vlA4SbTg+AbA3bP363l+w==}
+ engines: {node: '>= 20'}
+


This lockfile now includes @vercel/oidc@3.1.0 with engines: { node: '>= 20' } as a transitive dependency of ai. That conflicts with the repo’s declared Node support (>=18) and may fail CI or consumer installs when engines are enforced. Please either align the repo/package engines.node to >=20 or adjust the ai dependency strategy/version to avoid pulling Node>=20-only transitive deps.

Initial plan
734f913

CopilotAI assigned Copilot and hotlong Apr 1, 2026

Copilotstarted work on behalf of hotlong April 1, 2026 01:57 View session

CopilotAI linked an issue Apr 1, 2026 that may be closed by this pull request
AI chat协议与数据结构完全对齐Vercel/ai（移除自定义协议与类型定义） #1027
Closed
9 tasks

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plan: align AI chat protocol with Vercel/ai SDK
6bda8e8
Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/2515d700-01d1-4303-8678-41f0ce9674da Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

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CopilotAI changed the title ~~[WIP] Remove custom AI chat protocol and type definitions~~Align AI chat protocol with Vercel AI SDK — remove custom types and schemasApr 1, 2026

CopilotAI requested a review from hotlong April 1, 2026 02:56

Copilot stopped work on behalf of hotlong due to an error April 1, 2026 02:56
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Copilot stopped work on behalf of hotlong due to an error April 1, 2026 03:57
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Copilotstarted work on behalf of hotlong April 1, 2026 04:22 View session

CopilotAIand others added 6 commits April 1, 2026 04:39

refactor: migrate service-ai to Vercel AI SDK types, fix documentation
27f18e4
Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/7b5017d9-7b75-41e6-a0ad-6eb250b8d770 Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

refactor: address code review — extract stream helpers, improve type …
bcf879f
…narrowing Agent-Logs-Url: https://github.com/objectstack-ai/spec/sessions/7b5017d9-7b75-41e6-a0ad-6eb250b8d770 Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Copilotfinished work on behalf of hotlong April 1, 2026 04:59

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hotlong marked this pull request as ready for review April 1, 2026 05:02

CopilotAI review requested due to automatic review settings April 1, 2026 05:02

hotlong merged commit 37c0f8e into mainApr 1, 2026
3 of 4 checks passed

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Align AI chat protocol with Vercel AI SDK — remove custom types and schemas - #1028

Align AI chat protocol with Vercel AI SDK — remove custom types and schemas#1028
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Re-export Vercel AI SDK types as canonical

Update service contracts

Remove redundant chat wire protocol

Migrate packages/services/service-ai to canonical Vercel types

Fix documentation

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Migrate `packages/services/service-ai` to canonical Vercel types

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