diff --git a/bun.lock b/bun.lock
index 907c04c31d..697bc8ceff 100644
--- a/bun.lock
+++ b/bun.lock
@@ -690,6 +690,7 @@
       "version": "1.17.14",
       "dependencies": {
         "@ai-sdk/provider": "3.0.8",
+        "@opencode-ai/schema": "workspace:*",
         "@opencode-ai/sdk": "workspace:*",
         "effect": "catalog:",
         "zod": "catalog:",
@@ -752,6 +753,7 @@
       "dependencies": {
         "@opencode-ai/client": "workspace:*",
         "@opencode-ai/core": "workspace:*",
+        "@opencode-ai/schema": "workspace:*",
         "@opencode-ai/server": "workspace:*",
         "effect": "catalog:",
       },
diff --git a/packages/client/test/contract-identity.test.ts b/packages/client/test/contract-identity.test.ts
index 64a2e958ce..d54a48e938 100644
--- a/packages/client/test/contract-identity.test.ts
+++ b/packages/client/test/contract-identity.test.ts
@@ -21,6 +21,14 @@ import { Api } from "@opencode-ai/server/api"
 import { compile, emitPromise } from "@opencode-ai/httpapi-codegen"
 import { ClientApi, endpointNames, groupNames, omitEndpoints } from "../src/contract"
 
+const Client = await import("../src/effect")
+
+test("effect entrypoint exposes canonical Schema contracts", () => {
+  expect(Client.Agent).toBe(Agent)
+  expect(Client.Model).toBe(Model)
+  expect(Client.Session).toBe(Session)
+})
+
 test("Core and Server reuse the authoritative Schema and Protocol values", () => {
   expect(AgentV2.ID).toBe(Agent.ID)
   expect(CoreLocation.Ref).toBe(Location.Ref)
diff --git a/packages/core/src/session/store.ts b/packages/core/src/session/store.ts
index 273444d25c..f416e3eb5a 100644
--- a/packages/core/src/session/store.ts
+++ b/packages/core/src/session/store.ts
@@ -7,20 +7,20 @@ import { makeGlobalNode } from "../effect/app-node"
 import { SessionHistory } from "./history"
 import { MessageDecodeError } from "./error"
 import { SessionMessage } from "./message"
-import { SessionSchema } from "./schema"
+import { Session } from "@opencode-ai/schema/session"
 import { SessionMessageTable, SessionTable } from "./sql"
 import { fromRow } from "./info"
 
 export interface Interface {
-  readonly get: (sessionID: SessionSchema.ID) => Effect.Effect<SessionSchema.Info | undefined>
-  readonly context: (sessionID: SessionSchema.ID) => Effect.Effect<SessionMessage.Message[], MessageDecodeError>
+  readonly get: (sessionID: Session.ID) => Effect.Effect<Session.Info | undefined>
+  readonly context: (sessionID: Session.ID) => Effect.Effect<SessionMessage.Message[], MessageDecodeError>
   readonly runnerContext: (
-    sessionID: SessionSchema.ID,
+    sessionID: Session.ID,
     baselineSeq: number,
   ) => Effect.Effect<SessionMessage.Message[], MessageDecodeError>
   readonly message: (
     messageID: SessionMessage.ID,
-  ) => Effect.Effect<{ readonly sessionID: SessionSchema.ID; readonly message: SessionMessage.Message } | undefined>
+  ) => Effect.Effect<{ readonly sessionID: Session.ID; readonly message: SessionMessage.Message } | undefined>
 }
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/v2/SessionStore") {}
@@ -51,7 +51,7 @@ const layer = Layer.effect(
           .pipe(Effect.orDie)
         return row
           ? {
-              sessionID: SessionSchema.ID.make(row.session_id),
+              sessionID: Session.ID.make(row.session_id),
               message: yield* decodeMessage({ ...row.data, id: row.id, type: row.type }).pipe(Effect.orDie),
             }
           : undefined
diff --git a/packages/plugin/package.json b/packages/plugin/package.json
index 3069aa104f..8ed8ddb3eb 100644
--- a/packages/plugin/package.json
+++ b/packages/plugin/package.json
@@ -5,6 +5,7 @@
   "type": "module",
   "license": "MIT",
   "scripts": {
+    "test": "bun test --timeout 5000",
     "typecheck": "tsgo --noEmit",
     "build": "tsc"
   },
@@ -22,6 +23,7 @@
   ],
   "dependencies": {
     "@ai-sdk/provider": "3.0.8",
+    "@opencode-ai/schema": "workspace:*",
     "@opencode-ai/sdk": "workspace:*",
     "effect": "catalog:",
     "zod": "catalog:"
diff --git a/packages/plugin/src/v2/effect/agent.ts b/packages/plugin/src/v2/effect/agent.ts
index 9ded7b831d..d3d43cbb52 100644
--- a/packages/plugin/src/v2/effect/agent.ts
+++ b/packages/plugin/src/v2/effect/agent.ts
@@ -1,11 +1,12 @@
-import type { AgentV2Info } from "@opencode-ai/sdk/v2/types"
+import type { Agent } from "@opencode-ai/schema/agent"
+import type { Types } from "effect"
 import type { Hooks } from "./registration.js"
 
 export interface AgentDraft {
-  list(): readonly AgentV2Info[]
-  get(id: string): AgentV2Info | undefined
+  list(): readonly Types.DeepMutable<Agent.Info>[]
+  get(id: string): Types.DeepMutable<Agent.Info> | undefined
   default(id: string | undefined): void
-  update(id: string, update: (agent: AgentV2Info) => void): void
+  update(id: string, update: (agent: Types.DeepMutable<Agent.Info>) => void): void
   remove(id: string): void
 }
 
diff --git a/packages/plugin/src/v2/effect/aisdk.ts b/packages/plugin/src/v2/effect/aisdk.ts
index ddc292e384..2934edc27d 100644
--- a/packages/plugin/src/v2/effect/aisdk.ts
+++ b/packages/plugin/src/v2/effect/aisdk.ts
@@ -1,16 +1,16 @@
 import type { LanguageModelV3 } from "@ai-sdk/provider"
-import type { ModelV2Info } from "@opencode-ai/sdk/v2/types"
+import type { Model } from "@opencode-ai/schema/model"
 import type { Hooks } from "./registration.js"
 
 export type AISDKHooks = Hooks<{
   sdk: {
-    readonly model: ModelV2Info
+    readonly model: Model.Info
     readonly package: string
     readonly options: Record<string, any>
     sdk?: any
   }
   language: {
-    readonly model: ModelV2Info
+    readonly model: Model.Info
     readonly sdk: any
     readonly options: Record<string, any>
     language?: LanguageModelV3
diff --git a/packages/plugin/src/v2/effect/index.ts b/packages/plugin/src/v2/effect/index.ts
index f13614a54d..ff400347e2 100644
--- a/packages/plugin/src/v2/effect/index.ts
+++ b/packages/plugin/src/v2/effect/index.ts
@@ -1,3 +1,13 @@
 export type { PluginContext } from "./context.js"
 export { define } from "./plugin.js"
 export type { Plugin } from "./plugin.js"
+
+export { Agent } from "@opencode-ai/schema/agent"
+export { Command } from "@opencode-ai/schema/command"
+export { Connection } from "@opencode-ai/schema/connection"
+export { Credential } from "@opencode-ai/schema/credential"
+export { Integration } from "@opencode-ai/schema/integration"
+export { Model } from "@opencode-ai/schema/model"
+export { Provider } from "@opencode-ai/schema/provider"
+export { Reference } from "@opencode-ai/schema/reference"
+export { Skill } from "@opencode-ai/schema/skill"
diff --git a/packages/plugin/src/v2/promise/aisdk.ts b/packages/plugin/src/v2/promise/aisdk.ts
index ddc292e384..2934edc27d 100644
--- a/packages/plugin/src/v2/promise/aisdk.ts
+++ b/packages/plugin/src/v2/promise/aisdk.ts
@@ -1,16 +1,16 @@
 import type { LanguageModelV3 } from "@ai-sdk/provider"
-import type { ModelV2Info } from "@opencode-ai/sdk/v2/types"
+import type { Model } from "@opencode-ai/schema/model"
 import type { Hooks } from "./registration.js"
 
 export type AISDKHooks = Hooks<{
   sdk: {
-    readonly model: ModelV2Info
+    readonly model: Model.Info
     readonly package: string
     readonly options: Record<string, any>
     sdk?: any
   }
   language: {
-    readonly model: ModelV2Info
+    readonly model: Model.Info
     readonly sdk: any
     readonly options: Record<string, any>
     language?: LanguageModelV3
diff --git a/packages/plugin/src/v2/promise/index.ts b/packages/plugin/src/v2/promise/index.ts
index 8287955657..d3f94ef549 100644
--- a/packages/plugin/src/v2/promise/index.ts
+++ b/packages/plugin/src/v2/promise/index.ts
@@ -10,3 +10,13 @@ export type { CommandDraft, CommandHooks } from "./command.js"
 export type { IntegrationDraft, IntegrationHooks, IntegrationMethodRegistration } from "./integration.js"
 export type { ReferenceDraft, ReferenceHooks } from "./reference.js"
 export type { SkillDraft, SkillHooks } from "./skill.js"
+
+export { Agent } from "@opencode-ai/schema/agent"
+export { Command } from "@opencode-ai/schema/command"
+export { Connection } from "@opencode-ai/schema/connection"
+export { Credential } from "@opencode-ai/schema/credential"
+export { Integration } from "@opencode-ai/schema/integration"
+export { Model } from "@opencode-ai/schema/model"
+export { Provider } from "@opencode-ai/schema/provider"
+export { Reference } from "@opencode-ai/schema/reference"
+export { Skill } from "@opencode-ai/schema/skill"
diff --git a/packages/plugin/test/contract-identity.test.ts b/packages/plugin/test/contract-identity.test.ts
new file mode 100644
index 0000000000..1144a49344
--- /dev/null
+++ b/packages/plugin/test/contract-identity.test.ts
@@ -0,0 +1,40 @@
+import { expect, test } from "bun:test"
+import { Agent } from "@opencode-ai/schema/agent"
+import { Command } from "@opencode-ai/schema/command"
+import { Connection } from "@opencode-ai/schema/connection"
+import { Credential } from "@opencode-ai/schema/credential"
+import { Integration } from "@opencode-ai/schema/integration"
+import { Model } from "@opencode-ai/schema/model"
+import { Provider } from "@opencode-ai/schema/provider"
+import { Reference } from "@opencode-ai/schema/reference"
+import { Skill } from "@opencode-ai/schema/skill"
+
+const Plugin = await import("../src/v2/effect/index")
+const PromisePlugin = await import("../src/v2/promise/index")
+
+test.each([
+  ["effect", Plugin],
+  ["promise", PromisePlugin],
+])("%s entrypoint exposes its canonical Schema contracts", (_, entrypoint) => {
+  expect(entrypoint.Agent).toBe(Agent)
+  expect(entrypoint.Command).toBe(Command)
+  expect(entrypoint.Connection).toBe(Connection)
+  expect(entrypoint.Credential).toBe(Credential)
+  expect(entrypoint.Integration).toBe(Integration)
+  expect(entrypoint.Model).toBe(Model)
+  expect(entrypoint.Provider).toBe(Provider)
+  expect(entrypoint.Reference).toBe(Reference)
+  expect(entrypoint.Skill).toBe(Skill)
+  expect(Object.keys(entrypoint).sort()).toEqual([
+    "Agent",
+    "Command",
+    "Connection",
+    "Credential",
+    "Integration",
+    "Model",
+    "Provider",
+    "Reference",
+    "Skill",
+    "define",
+  ])
+})
diff --git a/packages/plugin/tsconfig.json b/packages/plugin/tsconfig.json
index f8e9370d86..f25b5898b9 100644
--- a/packages/plugin/tsconfig.json
+++ b/packages/plugin/tsconfig.json
@@ -4,9 +4,9 @@
   "compilerOptions": {
     "rootDir": "src",
     "outDir": "dist",
-    "module": "nodenext",
+    "module": "esnext",
     "declaration": true,
-    "moduleResolution": "nodenext",
+    "moduleResolution": "bundler",
     "lib": ["es2022", "dom", "dom.iterable"]
   },
   "include": ["src"]
diff --git a/packages/schema/AGENTS.md b/packages/schema/AGENTS.md
index 1d5747d539..400b4b312b 100644
--- a/packages/schema/AGENTS.md
+++ b/packages/schema/AGENTS.md
@@ -34,6 +34,13 @@
 - Use flat top-level exports plus the package's existing namespace projection pattern, for example `export * as SessionMessage from "./session-message"`.
 - Keep standalone ID modules only when they prevent real cycles or heavy dependency edges. Inline one-off IDs into their owning contract module when no cycle exists.
 
+## Public Re-exports
+
+- Public leaf packages re-export the canonical domain namespaces used by their APIs so consumers install and version one package. Keep the list curated by public API reachability rather than mirroring the Schema root.
+- Re-export directly from `@opencode-ai/schema/<domain>` and preserve the exact canonical values and types. Do not wrap schemas, duplicate definitions, or route exports through another facade package.
+- Internal packages import contracts directly from their canonical Schema owner. Import a Core domain facade only when runtime behavior from that facade is required.
+- Resolve name collisions by retaining the domain namespace and qualifying its members, such as `Session.Info` and `Agent.Info`. Do not introduce aliases such as `SessionSchema`, `AgentSchema`, or `ModelSchema`.
+
 ## Naming
 
 - Exported schema values and namespace objects use `PascalCase`.
diff --git a/packages/sdk-next/package.json b/packages/sdk-next/package.json
index 55a891a10f..dab2f9b17e 100644
--- a/packages/sdk-next/package.json
+++ b/packages/sdk-next/package.json
@@ -14,6 +14,7 @@
   "dependencies": {
     "@opencode-ai/client": "workspace:*",
     "@opencode-ai/core": "workspace:*",
+    "@opencode-ai/schema": "workspace:*",
     "@opencode-ai/server": "workspace:*",
     "effect": "catalog:"
   },
diff --git a/packages/sdk-next/src/index.ts b/packages/sdk-next/src/index.ts
index fc23219fc4..dbb07ec1c9 100644
--- a/packages/sdk-next/src/index.ts
+++ b/packages/sdk-next/src/index.ts
@@ -2,16 +2,25 @@ export * as OpenCode from "./opencode"
 export * as Tool from "./tool"
 
 export { ClientError } from "@opencode-ai/client/effect"
-export {
-  AbsolutePath,
-  Agent,
-  Location,
-  Model,
-  Prompt,
-  Provider,
-  RelativePath,
-  Session,
-  SessionInput,
-  SessionMessage,
-} from "@opencode-ai/client/effect"
 export type { OpenCodeEvent } from "@opencode-ai/client/effect"
+export { Agent } from "@opencode-ai/schema/agent"
+export { Command } from "@opencode-ai/schema/command"
+export { Credential } from "@opencode-ai/schema/credential"
+export { FileSystem } from "@opencode-ai/schema/filesystem"
+export { Integration } from "@opencode-ai/schema/integration"
+export { Location } from "@opencode-ai/schema/location"
+export { Model } from "@opencode-ai/schema/model"
+export { Permission } from "@opencode-ai/schema/permission"
+export { PermissionSaved } from "@opencode-ai/schema/permission-saved"
+export { Project } from "@opencode-ai/schema/project"
+export { ProjectCopy } from "@opencode-ai/schema/project-copy"
+export { Prompt } from "@opencode-ai/schema/prompt"
+export { Provider } from "@opencode-ai/schema/provider"
+export { Pty } from "@opencode-ai/schema/pty"
+export { Question } from "@opencode-ai/schema/question"
+export { Reference } from "@opencode-ai/schema/reference"
+export { AbsolutePath, RelativePath } from "@opencode-ai/schema/schema"
+export { Session } from "@opencode-ai/schema/session"
+export { SessionInput } from "@opencode-ai/schema/session-input"
+export { SessionMessage } from "@opencode-ai/schema/session-message"
+export { Skill } from "@opencode-ai/schema/skill"
diff --git a/packages/sdk-next/test/contract-identity.test.ts b/packages/sdk-next/test/contract-identity.test.ts
new file mode 100644
index 0000000000..96b10d6918
--- /dev/null
+++ b/packages/sdk-next/test/contract-identity.test.ts
@@ -0,0 +1,39 @@
+import { expect, test } from "bun:test"
+import { Agent } from "@opencode-ai/schema/agent"
+import { Model } from "@opencode-ai/schema/model"
+import { Session } from "@opencode-ai/schema/session"
+
+const SDK = await import("../src/index")
+
+test("re-exports canonical contracts directly from Schema", () => {
+  expect(SDK.Agent).toBe(Agent)
+  expect(SDK.Model).toBe(Model)
+  expect(SDK.Session).toBe(Session)
+  expect(Object.keys(SDK).sort()).toEqual([
+    "AbsolutePath",
+    "Agent",
+    "ClientError",
+    "Command",
+    "Credential",
+    "FileSystem",
+    "Integration",
+    "Location",
+    "Model",
+    "OpenCode",
+    "Permission",
+    "PermissionSaved",
+    "Project",
+    "ProjectCopy",
+    "Prompt",
+    "Provider",
+    "Pty",
+    "Question",
+    "Reference",
+    "RelativePath",
+    "Session",
+    "SessionInput",
+    "SessionMessage",
+    "Skill",
+    "Tool",
+  ])
+})