diff --git a/packages/core/src/aisdk.ts b/packages/core/src/aisdk.ts
index 8640e3cf1..d8962d250 100644
--- a/packages/core/src/aisdk.ts
+++ b/packages/core/src/aisdk.ts
@@ -164,7 +164,7 @@ export const layer = Layer.effect(
             {},
           )
           .pipe(initError(model.providerID))
-        const language = yield* Effect.sync(() => result.language ?? sdk.languageModel(model.apiID)).pipe(
+        const language = yield* Effect.sync(() => result.language ?? sdk.languageModel(model.api.id)).pipe(
           initError(model.providerID),
         )
         languages.set(key, language)
diff --git a/packages/core/src/catalog.ts b/packages/core/src/catalog.ts
index d5633a82e..e7103627a 100644
--- a/packages/core/src/catalog.ts
+++ b/packages/core/src/catalog.ts
@@ -99,7 +99,7 @@ export const layer = Layer.effect(
       const provider = state.get().providers.get(model.providerID)!.provider
       const api =
         model.api.type === "native" && !model.api.url && Object.keys(model.api.settings).length === 0
-          ? provider.api
+          ? { ...provider.api, id: model.api.id }
           : model.api.type === "aisdk" && provider.api.type === "aisdk" && !model.api.url
             ? { ...model.api, url: provider.api.url, settings: { ...provider.api.settings, ...model.api.settings } }
             : model.api.type === "aisdk" && provider.api.type === "aisdk"
diff --git a/packages/core/src/config/plugin/provider.ts b/packages/core/src/config/plugin/provider.ts
index 42eb17686..6127c877f 100644
--- a/packages/core/src/config/plugin/provider.ts
+++ b/packages/core/src/config/plugin/provider.ts
@@ -32,10 +32,9 @@ export const Plugin = PluginV2.define({
 
           for (const [id, config] of Object.entries(item.models ?? {})) {
             catalog.model.update(providerID, ModelV2.ID.make(id), (model) => {
-              if (config.api_id !== undefined) model.apiID = config.api_id
               if (config.family !== undefined) model.family = config.family
               if (config.name !== undefined) model.name = config.name
-              if (config.api !== undefined) model.api = { ...config.api }
+              if (config.api !== undefined) model.api = { ...model.api, ...config.api }
               if (config.capabilities !== undefined) {
                 model.capabilities = {
                   tools: config.capabilities.tools,
diff --git a/packages/core/src/config/provider.ts b/packages/core/src/config/provider.ts
index 94e7546dd..1b5475707 100644
--- a/packages/core/src/config/provider.ts
+++ b/packages/core/src/config/provider.ts
@@ -30,11 +30,24 @@ class Limit extends Schema.Class<Limit>("ConfigV2.Model.Limit")({
   output: Schema.Int.pipe(Schema.optional),
 }) {}
 
+const ModelApi = Schema.Union([
+  Schema.Struct({
+    id: ModelV2.ID.pipe(Schema.optional),
+    ...ProviderV2.AISDK.fields,
+  }),
+  Schema.Struct({
+    id: ModelV2.ID.pipe(Schema.optional),
+    ...ProviderV2.Native.fields,
+  }),
+  Schema.Struct({
+    id: ModelV2.ID,
+  }),
+])
+
 class Model extends Schema.Class<Model>("ConfigV2.Model")({
-  api_id: ModelV2.ID.pipe(Schema.optional),
   family: ModelV2.Family.pipe(Schema.optional),
   name: Schema.String.pipe(Schema.optional),
-  api: ProviderV2.Api.pipe(Schema.optional),
+  api: ModelApi.pipe(Schema.optional),
   capabilities: ModelV2.Capabilities.pipe(Schema.optional),
   request: Schema.Struct({
     ...Request.fields,
diff --git a/packages/core/src/model.ts b/packages/core/src/model.ts
index ed1741341..a57647c4d 100644
--- a/packages/core/src/model.ts
+++ b/packages/core/src/model.ts
@@ -40,13 +40,24 @@ export const Ref = Schema.Struct({
 })
 export type Ref = typeof Ref.Type
 
+export const Api = Schema.Union([
+  Schema.Struct({
+    id: ID,
+    ...ProviderV2.AISDK.fields,
+  }),
+  Schema.Struct({
+    id: ID,
+    ...ProviderV2.Native.fields,
+  }),
+]).pipe(Schema.toTaggedUnion("type"))
+export type Api = typeof Api.Type
+
 export class Info extends Schema.Class<Info>("ModelV2.Info")({
   id: ID,
-  apiID: ID,
   providerID: ProviderV2.ID,
   family: Family.pipe(Schema.optional),
   name: Schema.String,
-  api: ProviderV2.Api,
+  api: Api,
   capabilities: Capabilities,
   request: Schema.Struct({
     ...ProviderV2.Request.fields,
@@ -71,10 +82,10 @@ export class Info extends Schema.Class<Info>("ModelV2.Info")({
   static empty(providerID: ProviderV2.ID, modelID: ID): Info {
     return new Info({
       id: modelID,
-      apiID: modelID,
       providerID,
       name: modelID,
       api: {
+        id: modelID,
         type: "native",
         settings: {},
       },
diff --git a/packages/core/src/plugin/models-dev.ts b/packages/core/src/plugin/models-dev.ts
index 9523a2ede..d223e59f6 100644
--- a/packages/core/src/plugin/models-dev.ts
+++ b/packages/core/src/plugin/models-dev.ts
@@ -82,11 +82,13 @@ export const ModelsDevPlugin = PluginV2.define({
               draft.family = model.family ? ModelV2.Family.make(model.family) : undefined
               draft.api = model.provider?.npm
                 ? {
+                    id: draft.api.id,
                     type: "aisdk",
                     package: model.provider?.npm,
                     url: model.provider.api,
                   }
                 : {
+                    id: draft.api.id,
                     type: "native",
                     url: model.provider?.api,
                     settings: {},
diff --git a/packages/core/src/plugin/provider/amazon-bedrock.ts b/packages/core/src/plugin/provider/amazon-bedrock.ts
index 31df9ca12..daa0fd9f8 100644
--- a/packages/core/src/plugin/provider/amazon-bedrock.ts
+++ b/packages/core/src/plugin/provider/amazon-bedrock.ts
@@ -92,7 +92,7 @@ export const AmazonBedrockPlugin = PluginV2.define({
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.amazonBedrock) return
         const region = typeof evt.options.region === "string" ? evt.options.region : process.env.AWS_REGION
-        evt.language = evt.sdk.languageModel(resolveModelID(evt.model.apiID, region))
+        evt.language = evt.sdk.languageModel(resolveModelID(evt.model.api.id, region))
       }),
     }
   }),
diff --git a/packages/core/src/plugin/provider/azure.ts b/packages/core/src/plugin/provider/azure.ts
index cc8cf3c65..173fd3662 100644
--- a/packages/core/src/plugin/provider/azure.ts
+++ b/packages/core/src/plugin/provider/azure.ts
@@ -45,7 +45,7 @@ export const AzurePlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.azure) return
-        evt.language = selectLanguage(evt.sdk, evt.model.apiID, Boolean(evt.options.useCompletionUrls))
+        evt.language = selectLanguage(evt.sdk, evt.model.api.id, Boolean(evt.options.useCompletionUrls))
       }),
     }
   }),
@@ -69,7 +69,7 @@ export const AzureCognitiveServicesPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.make("azure-cognitive-services")) return
-        evt.language = selectLanguage(evt.sdk, evt.model.apiID, Boolean(evt.options.useCompletionUrls))
+        evt.language = selectLanguage(evt.sdk, evt.model.api.id, Boolean(evt.options.useCompletionUrls))
       }),
     }
   }),
diff --git a/packages/core/src/plugin/provider/cloudflare-workers-ai.ts b/packages/core/src/plugin/provider/cloudflare-workers-ai.ts
index 1ad3834c9..ca19e63c0 100644
--- a/packages/core/src/plugin/provider/cloudflare-workers-ai.ts
+++ b/packages/core/src/plugin/provider/cloudflare-workers-ai.ts
@@ -30,7 +30,7 @@ export const CloudflareWorkersAIPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== providerID) return
-        evt.language = evt.sdk.languageModel(evt.model.apiID)
+        evt.language = evt.sdk.languageModel(evt.model.api.id)
       }),
     }
   }),
diff --git a/packages/core/src/plugin/provider/github-copilot.ts b/packages/core/src/plugin/provider/github-copilot.ts
index 20b1ad6d6..1fc7c0c79 100644
--- a/packages/core/src/plugin/provider/github-copilot.ts
+++ b/packages/core/src/plugin/provider/github-copilot.ts
@@ -23,12 +23,12 @@ export const GithubCopilotPlugin = PluginV2.define({
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.githubCopilot) return
         if (evt.sdk.responses === undefined && evt.sdk.chat === undefined) {
-          evt.language = evt.sdk.languageModel(evt.model.apiID)
+          evt.language = evt.sdk.languageModel(evt.model.api.id)
           return
         }
-        evt.language = shouldUseResponses(evt.model.apiID)
-          ? evt.sdk.responses(evt.model.apiID)
-          : evt.sdk.chat(evt.model.apiID)
+        evt.language = shouldUseResponses(evt.model.api.id)
+          ? evt.sdk.responses(evt.model.api.id)
+          : evt.sdk.chat(evt.model.api.id)
       }),
       "catalog.transform": Effect.fn(function* (evt) {
         const item = evt.provider.get(ProviderV2.ID.githubCopilot)
diff --git a/packages/core/src/plugin/provider/gitlab.ts b/packages/core/src/plugin/provider/gitlab.ts
index f9a0be6aa..9de090a95 100644
--- a/packages/core/src/plugin/provider/gitlab.ts
+++ b/packages/core/src/plugin/provider/gitlab.ts
@@ -34,7 +34,7 @@ export const GitLabPlugin = PluginV2.define({
         if (evt.model.providerID !== ProviderV2.ID.gitlab) return
         const featureFlags =
           typeof evt.options.featureFlags === "object" && evt.options.featureFlags ? evt.options.featureFlags : {}
-        if (evt.model.apiID.startsWith("duo-workflow-")) {
+        if (evt.model.api.id.startsWith("duo-workflow-")) {
           const gitlab = yield* Effect.promise(() => import("gitlab-ai-provider")).pipe(Effect.orDie)
           const workflowRef =
             typeof evt.model.request.body.workflowRef === "string" ? evt.model.request.body.workflowRef : undefined
@@ -43,7 +43,7 @@ export const GitLabPlugin = PluginV2.define({
               ? evt.model.request.body.workflowDefinition
               : undefined
           const language = evt.sdk.workflowChat(
-            gitlab.isWorkflowModel(evt.model.apiID) ? evt.model.apiID : "duo-workflow",
+            gitlab.isWorkflowModel(evt.model.api.id) ? evt.model.api.id : "duo-workflow",
             {
               featureFlags,
               workflowDefinition,
@@ -53,7 +53,7 @@ export const GitLabPlugin = PluginV2.define({
           evt.language = language
           return
         }
-        evt.language = evt.sdk.agenticChat(evt.model.apiID, {
+        evt.language = evt.sdk.agenticChat(evt.model.api.id, {
           aiGatewayHeaders: evt.options.aiGatewayHeaders,
           featureFlags,
         })
diff --git a/packages/core/src/plugin/provider/google-vertex.ts b/packages/core/src/plugin/provider/google-vertex.ts
index abf6c0e0c..d996a1f24 100644
--- a/packages/core/src/plugin/provider/google-vertex.ts
+++ b/packages/core/src/plugin/provider/google-vertex.ts
@@ -99,7 +99,7 @@ export const GoogleVertexPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.googleVertex) return
-        evt.language = evt.sdk.languageModel(String(evt.model.apiID).trim())
+        evt.language = evt.sdk.languageModel(String(evt.model.api.id).trim())
       }),
     }
   }),
@@ -155,7 +155,7 @@ export const GoogleVertexAnthropicPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.make("google-vertex-anthropic")) return
-        evt.language = evt.sdk.languageModel(String(evt.model.apiID).trim())
+        evt.language = evt.sdk.languageModel(String(evt.model.api.id).trim())
       }),
     }
   }),
diff --git a/packages/core/src/plugin/provider/openai.ts b/packages/core/src/plugin/provider/openai.ts
index 61f409ee6..1218625a4 100644
--- a/packages/core/src/plugin/provider/openai.ts
+++ b/packages/core/src/plugin/provider/openai.ts
@@ -14,7 +14,7 @@ export const OpenAIPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.openai) return
-        evt.language = evt.sdk.responses(evt.model.apiID)
+        evt.language = evt.sdk.responses(evt.model.api.id)
       }),
       "catalog.transform": Effect.fn(function* (evt) {
         for (const item of evt.provider.list()) {
diff --git a/packages/core/src/plugin/provider/sap-ai-core.ts b/packages/core/src/plugin/provider/sap-ai-core.ts
index 7c57b785b..47c8b7eaa 100644
--- a/packages/core/src/plugin/provider/sap-ai-core.ts
+++ b/packages/core/src/plugin/provider/sap-ai-core.ts
@@ -37,7 +37,7 @@ export const SapAICorePlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.make("sap-ai-core")) return
-        evt.language = evt.sdk(evt.model.apiID)
+        evt.language = evt.sdk(evt.model.api.id)
       }),
     }
   }),
diff --git a/packages/core/src/plugin/provider/xai.ts b/packages/core/src/plugin/provider/xai.ts
index b54aa7374..4e9d53e47 100644
--- a/packages/core/src/plugin/provider/xai.ts
+++ b/packages/core/src/plugin/provider/xai.ts
@@ -13,7 +13,7 @@ export const XAIPlugin = PluginV2.define({
       }),
       "aisdk.language": Effect.fn(function* (evt) {
         if (evt.model.providerID !== ProviderV2.ID.make("xai")) return
-        evt.language = evt.sdk.responses(evt.model.apiID)
+        evt.language = evt.sdk.responses(evt.model.api.id)
       }),
     }
   }),
diff --git a/packages/core/src/provider.ts b/packages/core/src/provider.ts
index eae4ab990..3f99cedc1 100644
--- a/packages/core/src/provider.ts
+++ b/packages/core/src/provider.ts
@@ -25,14 +25,14 @@ export type ID = typeof ID.Type
 export const ModelID = Schema.String.pipe(Schema.brand("ModelID"))
 export type ModelID = typeof ModelID.Type
 
-const AISDK = Schema.Struct({
+export const AISDK = Schema.Struct({
   type: Schema.Literal("aisdk"),
   package: Schema.String,
   url: Schema.String.pipe(Schema.optional),
   settings: Schema.Record(Schema.String, Schema.Unknown).pipe(Schema.optional),
 })
 
-const Native = Schema.Struct({
+export const Native = Schema.Struct({
   type: Schema.Literal("native"),
   url: Schema.String.pipe(Schema.optional),
   settings: Schema.Record(Schema.String, Schema.Unknown),
diff --git a/packages/core/src/v1/config/migrate.ts b/packages/core/src/v1/config/migrate.ts
index 4b666dfd8..7c254b86e 100644
--- a/packages/core/src/v1/config/migrate.ts
+++ b/packages/core/src/v1/config/migrate.ts
@@ -205,12 +205,19 @@ function migrateModel(info: typeof ConfigProviderV1.Model.Type, packageName?: st
       : undefined
   const lowerer = ConfigProviderOptionsV1.get(info.provider?.npm ?? packageName)
   return {
-    api_id: info.id,
     family: info.family,
     name: info.name,
     api: info.provider?.npm
-      ? { type: "aisdk" as const, package: info.provider.npm, url: info.provider.api, settings: {} }
-      : undefined,
+      ? {
+          ...(info.id === undefined ? {} : { id: info.id }),
+          type: "aisdk" as const,
+          package: info.provider.npm,
+          url: info.provider.api,
+          settings: {},
+        }
+      : info.id === undefined
+        ? undefined
+        : { id: info.id },
     capabilities,
     request: (info.headers || info.options) && {
       headers: info.headers,
diff --git a/packages/core/test/catalog.test.ts b/packages/core/test/catalog.test.ts
index 08cbb4dbc..2f247ed0f 100644
--- a/packages/core/test/catalog.test.ts
+++ b/packages/core/test/catalog.test.ts
@@ -61,12 +61,18 @@ describe("CatalogV2", () => {
           }
         })
         catalog.model.update(providerID, modelID, (model) => {
-          model.api = { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://model.example.com" }
+          model.api = {
+            id: modelID,
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://model.example.com",
+          }
           model.request.body.baseURL = "https://override.example.com"
         })
       })
 
       expect((yield* catalog.model.get(providerID, modelID)).api).toEqual({
+        id: modelID,
         type: "aisdk",
         package: "@ai-sdk/openai-compatible",
         url: "https://override.example.com",
@@ -94,6 +100,7 @@ describe("CatalogV2", () => {
       })
 
       expect((yield* catalog.model.get(providerID, modelID)).api).toEqual({
+        id: modelID,
         type: "aisdk",
         package: "@ai-sdk/openai-compatible",
         url: "https://provider.example.com",
diff --git a/packages/core/test/config/provider.test.ts b/packages/core/test/config/provider.test.ts
index 273739662..2c3f0357f 100644
--- a/packages/core/test/config/provider.test.ts
+++ b/packages/core/test/config/provider.test.ts
@@ -66,7 +66,7 @@ describe("ConfigProviderPlugin.Plugin", () => {
                     request: request({ last: "last", shared: "last" }),
                     models: {
                       chat: {
-                        api_id: "api-chat",
+                        api: { id: "api-chat" },
                         name: "Last",
                         limit: { output: 75 },
                         request: request({ last: "last", shared: "last" }),
@@ -112,7 +112,7 @@ describe("ConfigProviderPlugin.Plugin", () => {
       expect(provider.enabled).toEqual({ via: "custom", data: {} })
       expect(provider.api).toEqual({ type: "aisdk", package: "custom-sdk", url: "https://example.test" })
       expect(provider.request.headers).toEqual({ first: "first", shared: "last", last: "last" })
-      expect(model.apiID).toBe(ModelV2.ID.make("api-chat"))
+      expect(model.api.id).toBe(ModelV2.ID.make("api-chat"))
       expect(model.name).toBe("Last")
       expect(model.capabilities).toEqual({ tools: true, input: ["text"], output: ["text"] })
       expect(model.enabled).toBe(false)
diff --git a/packages/core/test/plugin/provider-alibaba.test.ts b/packages/core/test/plugin/provider-alibaba.test.ts
index 06e6f969f..e2fbb8061 100644
--- a/packages/core/test/plugin/provider-alibaba.test.ts
+++ b/packages/core/test/plugin/provider-alibaba.test.ts
@@ -53,13 +53,13 @@ describe("AlibabaPlugin", () => {
     }),
   )
 
-  it.effect("uses the old default languageModel(apiID) behavior", () =>
+  it.effect("uses the old default languageModel(api.id) behavior", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       yield* plugin.add(AlibabaPlugin)
-      const item = model("alibaba", "alias", { apiID: ModelV2.ID.make("qwen-plus") })
+      const item = model("alibaba", "alias", { api: { id: ModelV2.ID.make("qwen-plus") } })
       const result = yield* plugin.trigger("aisdk.sdk", { model: item, package: "@ai-sdk/alibaba", options: {} }, {})
-      const language = result.sdk?.languageModel(item.apiID)
+      const language = result.sdk?.languageModel(item.api.id)
       expect(language?.modelId).toBe("qwen-plus")
       expect(language?.provider).toBe("alibaba.chat")
     }),
diff --git a/packages/core/test/plugin/provider-cloudflare-workers-ai.test.ts b/packages/core/test/plugin/provider-cloudflare-workers-ai.test.ts
index cd71cea54..d0a05e67a 100644
--- a/packages/core/test/plugin/provider-cloudflare-workers-ai.test.ts
+++ b/packages/core/test/plugin/provider-cloudflare-workers-ai.test.ts
@@ -253,7 +253,7 @@ describe("CloudflareWorkersAIPlugin", () => {
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("cloudflare-workers-ai", "alias", { apiID: ModelV2.ID.make("@cf/api-model") }),
+          model: model("cloudflare-workers-ai", "alias", { api: { id: ModelV2.ID.make("@cf/api-model") } }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
diff --git a/packages/core/test/plugin/provider-cohere.test.ts b/packages/core/test/plugin/provider-cohere.test.ts
index 54bec2cec..a646c3eb6 100644
--- a/packages/core/test/plugin/provider-cohere.test.ts
+++ b/packages/core/test/plugin/provider-cohere.test.ts
@@ -73,7 +73,7 @@ describe("CoherePlugin", () => {
       yield* plugin.add(CoherePlugin)
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("cohere", "alias", { apiID: ModelV2.ID.make("command-r-plus") }), sdk, options: {} },
+        { model: model("cohere", "alias", { api: { id: ModelV2.ID.make("command-r-plus") } }), sdk, options: {} },
         {},
       )
 
diff --git a/packages/core/test/plugin/provider-dynamic.test.ts b/packages/core/test/plugin/provider-dynamic.test.ts
index 7ffa89986..2b0be314b 100644
--- a/packages/core/test/plugin/provider-dynamic.test.ts
+++ b/packages/core/test/plugin/provider-dynamic.test.ts
@@ -158,15 +158,14 @@ describe("DynamicProviderPlugin", () => {
     }),
   )
 
-  itWithAISDK.effect("uses the model apiID for the default language model", () =>
+  itWithAISDK.effect("uses the model api.id for the default language model", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
       yield* plugin.add(dynamicPlugin())
       const language = yield* aisdk.language(
         model("custom", "alias", {
-          apiID: ModelV2.ID.make("test-model-api"),
-          api: { type: "aisdk", package: fixtureProvider },
+          api: { id: ModelV2.ID.make("test-model-api"), type: "aisdk", package: fixtureProvider },
         }),
       )
       expect(language).toMatchObject({ modelID: "test-model-api", options: { name: "custom" } })
diff --git a/packages/core/test/plugin/provider-github-copilot.test.ts b/packages/core/test/plugin/provider-github-copilot.test.ts
index c07f70597..f16b177e6 100644
--- a/packages/core/test/plugin/provider-github-copilot.test.ts
+++ b/packages/core/test/plugin/provider-github-copilot.test.ts
@@ -61,7 +61,7 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "alias", { apiID: ModelV2.ID.make("claude-sonnet-4") }),
+          model: model("github-copilot", "alias", { api: { id: ModelV2.ID.make("claude-sonnet-4") } }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },
@@ -119,7 +119,7 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "default", { apiID: ModelV2.ID.make("gpt-5") }),
+          model: model("github-copilot", "default", { api: { id: ModelV2.ID.make("gpt-5") } }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -128,7 +128,7 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "small", { apiID: ModelV2.ID.make("gpt-5-mini") }),
+          model: model("github-copilot", "small", { api: { id: ModelV2.ID.make("gpt-5-mini") } }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -137,7 +137,7 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "sonnet", { apiID: ModelV2.ID.make("claude-sonnet-4") }),
+          model: model("github-copilot", "sonnet", { api: { id: ModelV2.ID.make("claude-sonnet-4") } }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
diff --git a/packages/core/test/plugin/provider-google.test.ts b/packages/core/test/plugin/provider-google.test.ts
index 0ff78bc18..9880ff3ae 100644
--- a/packages/core/test/plugin/provider-google.test.ts
+++ b/packages/core/test/plugin/provider-google.test.ts
@@ -51,8 +51,8 @@ describe("GooglePlugin", () => {
       yield* plugin.add(GooglePlugin)
       const language = yield* aisdk.language(
         model("custom-google", "alias", {
-          apiID: ModelV2.ID.make("gemini-api"),
           api: {
+            id: ModelV2.ID.make("gemini-api"),
             type: "aisdk",
             package: "@ai-sdk/google",
           },
diff --git a/packages/core/test/plugin/provider-groq.test.ts b/packages/core/test/plugin/provider-groq.test.ts
index 099e4eed7..c6db66b1c 100644
--- a/packages/core/test/plugin/provider-groq.test.ts
+++ b/packages/core/test/plugin/provider-groq.test.ts
@@ -75,15 +75,15 @@ describe("GroqPlugin", () => {
     }),
   )
 
-  aisdkIt.effect("uses the default languageModel(apiID) behavior", () =>
+  aisdkIt.effect("uses the default languageModel(api.id) behavior", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
       yield* plugin.add(GroqPlugin)
       const result = yield* aisdk.language(
         model("groq", "alias", {
-          apiID: ModelV2.ID.make("llama-api"),
           api: {
+            id: ModelV2.ID.make("llama-api"),
             type: "aisdk",
             package: "@ai-sdk/groq",
           },
diff --git a/packages/core/test/plugin/provider-helper.ts b/packages/core/test/plugin/provider-helper.ts
index 212fbf5a5..1f4dbfb5a 100644
--- a/packages/core/test/plugin/provider-helper.ts
+++ b/packages/core/test/plugin/provider-helper.ts
@@ -60,7 +60,7 @@ type ProviderInput = Partial<Omit<ProviderV2.Info, "api" | "request">> & {
 }
 
 type ModelInput = Partial<Omit<ModelV2.Info, "api" | "request">> & {
-  api?: ProviderV2.Api
+  api?: (ProviderV2.Api & { id?: ModelV2.ID }) | { id: ModelV2.ID }
   request?: ModelV2.Info["request"]
 }
 
@@ -83,12 +83,16 @@ export function provider(providerID: string, options?: ProviderInput) {
 export function model(providerID: string, modelID: string, options?: ModelInput) {
   return new ModelV2.Info({
     ...ModelV2.Info.empty(ProviderV2.ID.make(providerID), ModelV2.ID.make(modelID)),
-    apiID: ModelV2.ID.make(modelID),
-    api: options?.api ?? {
-      type: "aisdk",
-      package: "test-provider",
-    },
     ...options,
+    api:
+      options?.api && "type" in options.api
+        ? { id: ModelV2.ID.make(modelID), ...options.api }
+        : {
+            id: ModelV2.ID.make(modelID),
+            ...options?.api,
+            type: "aisdk",
+            package: "test-provider",
+          },
     request: {
       headers: {},
       body: {},
diff --git a/packages/core/test/plugin/provider-mistral.test.ts b/packages/core/test/plugin/provider-mistral.test.ts
index f24ff53e5..b442d4f4d 100644
--- a/packages/core/test/plugin/provider-mistral.test.ts
+++ b/packages/core/test/plugin/provider-mistral.test.ts
@@ -87,7 +87,7 @@ describe("MistralPlugin", () => {
     }),
   )
 
-  it.effect("leaves Mistral language selection on the default sdk.languageModel(apiID) path", () =>
+  it.effect("leaves Mistral language selection on the default sdk.languageModel(api.id) path", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
@@ -95,10 +95,10 @@ describe("MistralPlugin", () => {
       yield* plugin.add(MistralPlugin)
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("mistral", "alias", { apiID: ModelV2.ID.make("mistral-large") }), sdk, options: {} },
+        { model: model("mistral", "alias", { api: { id: ModelV2.ID.make("mistral-large") } }), sdk, options: {} },
         {},
       )
-      const language = result.language ?? sdk.languageModel(result.model.apiID)
+      const language = result.language ?? sdk.languageModel(result.model.api.id)
       expect(calls).toEqual(["languageModel:mistral-large"])
       expect(language).toBeDefined()
     }),
diff --git a/packages/core/test/plugin/provider-openai.test.ts b/packages/core/test/plugin/provider-openai.test.ts
index 28a048e64..3aa38a4b1 100644
--- a/packages/core/test/plugin/provider-openai.test.ts
+++ b/packages/core/test/plugin/provider-openai.test.ts
@@ -46,7 +46,9 @@ describe("OpenAIPlugin", () => {
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("openai", "alias", { apiID: ModelV2.ID.make("gpt-5") }),
+          model: model("openai", "alias", {
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
diff --git a/packages/core/test/plugin/provider-perplexity.test.ts b/packages/core/test/plugin/provider-perplexity.test.ts
index d03f58337..444badd85 100644
--- a/packages/core/test/plugin/provider-perplexity.test.ts
+++ b/packages/core/test/plugin/provider-perplexity.test.ts
@@ -94,7 +94,7 @@ describe("PerplexityPlugin", () => {
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("perplexity", "alias", { apiID: ModelV2.ID.make("sonar") }),
+          model: model("perplexity", "alias", { api: { id: ModelV2.ID.make("sonar") } }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
diff --git a/packages/core/test/plugin/provider-togetherai.test.ts b/packages/core/test/plugin/provider-togetherai.test.ts
index 65090037b..3457c2ac8 100644
--- a/packages/core/test/plugin/provider-togetherai.test.ts
+++ b/packages/core/test/plugin/provider-togetherai.test.ts
@@ -90,7 +90,7 @@ describe("TogetherAIPlugin", () => {
 
       expect(result.language).toBeUndefined()
       expect(calls).toEqual([])
-      expect(result.language ?? fakeSelectorSdk(calls).languageModel(result.model.apiID)).toBeDefined()
+      expect(result.language ?? fakeSelectorSdk(calls).languageModel(result.model.api.id)).toBeDefined()
       expect(calls).toEqual(["languageModel:meta-llama/Llama-3.3-70B-Instruct-Turbo"])
     }),
   )
diff --git a/packages/core/test/plugin/provider-xai.test.ts b/packages/core/test/plugin/provider-xai.test.ts
index 6181fcccc..e505f8538 100644
--- a/packages/core/test/plugin/provider-xai.test.ts
+++ b/packages/core/test/plugin/provider-xai.test.ts
@@ -12,8 +12,8 @@ const it = testEffect(PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultL
 
 const model = new ModelV2.Info({
   ...ModelV2.Info.empty(ProviderV2.ID.make("xai"), ModelV2.ID.make("grok-4")),
-  apiID: ModelV2.ID.make("grok-4"),
   api: {
+    id: ModelV2.ID.make("grok-4"),
     type: "aisdk",
     package: "@ai-sdk/xai",
   },
@@ -72,7 +72,7 @@ describe("XAIPlugin", () => {
     }),
   )
 
-  it.effect("uses responses with the model apiID for xAI language models", () =>
+  it.effect("uses responses with the model api.id for xAI language models", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
@@ -81,7 +81,7 @@ describe("XAIPlugin", () => {
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: new ModelV2.Info({ ...model, id: ModelV2.ID.make("alias"), apiID: ModelV2.ID.make("grok-4") }),
+          model: new ModelV2.Info({ ...model, id: ModelV2.ID.make("alias") }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
diff --git a/packages/sdk/js/src/v2/gen/types.gen.ts b/packages/sdk/js/src/v2/gen/types.gen.ts
index 7d914f85e..c738c3871 100644
--- a/packages/sdk/js/src/v2/gen/types.gen.ts
+++ b/packages/sdk/js/src/v2/gen/types.gen.ts
@@ -2685,12 +2685,12 @@ export type EventTuiSessionSelect2 = {
 
 export type ModelV2Info = {
   id: string
-  apiID: string
   providerID: string
   family?: string
   name: string
   api:
     | {
+        id: string
         type: "aisdk"
         package: string
         url?: string
@@ -2699,6 +2699,7 @@ export type ModelV2Info = {
         }
       }
     | {
+        id: string
         type: "native"
         url?: string
         settings: {
@@ -3694,12 +3695,12 @@ export type EventPluginAdded = {
 
 export type ModelV2Info1 = {
   id: string
-  apiID: string
   providerID: string
   family?: string
   name: string
   api:
     | {
+        id: string
         type: "aisdk"
         package: string
         url?: string
@@ -3708,6 +3709,7 @@ export type ModelV2Info1 = {
         }
       }
     | {
+        id: string
         type: "native"
         url?: string
         settings: {
diff --git a/packages/sdk/openapi.json b/packages/sdk/openapi.json
index 1766883e6..ddceaa0b4 100644
--- a/packages/sdk/openapi.json
+++ b/packages/sdk/openapi.json
@@ -19300,9 +19300,6 @@
           "id": {
             "type": "string"
           },
-          "apiID": {
-            "type": "string"
-          },
           "providerID": {
             "type": "string"
           },
@@ -19317,6 +19314,9 @@
               {
                 "type": "object",
                 "properties": {
+                  "id": {
+                    "type": "string"
+                  },
                   "type": {
                     "type": "string",
                     "enum": ["aisdk"]
@@ -19331,12 +19331,15 @@
                     "type": "object"
                   }
                 },
-                "required": ["type", "package"],
+                "required": ["id", "type", "package"],
                 "additionalProperties": false
               },
               {
                 "type": "object",
                 "properties": {
+                  "id": {
+                    "type": "string"
+                  },
                   "type": {
                     "type": "string",
                     "enum": ["native"]
@@ -19348,7 +19351,7 @@
                     "type": "object"
                   }
                 },
-                "required": ["type", "settings"],
+                "required": ["id", "type", "settings"],
                 "additionalProperties": false
               }
             ]
@@ -19515,7 +19518,6 @@
         },
         "required": [
           "id",
-          "apiID",
           "providerID",
           "name",
           "api",
@@ -22371,9 +22373,6 @@
           "id": {
             "type": "string"
           },
-          "apiID": {
-            "type": "string"
-          },
           "providerID": {
             "type": "string"
           },
@@ -22388,6 +22387,9 @@
               {
                 "type": "object",
                 "properties": {
+                  "id": {
+                    "type": "string"
+                  },
                   "type": {
                     "type": "string",
                     "enum": ["aisdk"]
@@ -22402,12 +22404,15 @@
                     "type": "object"
                   }
                 },
-                "required": ["type", "package"],
+                "required": ["id", "type", "package"],
                 "additionalProperties": false
               },
               {
                 "type": "object",
                 "properties": {
+                  "id": {
+                    "type": "string"
+                  },
                   "type": {
                     "type": "string",
                     "enum": ["native"]
@@ -22419,7 +22424,7 @@
                     "type": "object"
                   }
                 },
-                "required": ["type", "settings"],
+                "required": ["id", "type", "settings"],
                 "additionalProperties": false
               }
             ]
@@ -22582,7 +22587,6 @@
         },
         "required": [
           "id",
-          "apiID",
           "providerID",
           "name",
           "api",
diff --git a/specs/v2/config.md b/specs/v2/config.md
index 5edfc1e4d..378ccfbd1 100644
--- a/specs/v2/config.md
+++ b/specs/v2/config.md
@@ -211,7 +211,7 @@ Provider, model, variant, and provisional agent `options` are authored as partia
 
 Keep provider `env` as an authored list of recognized credential environment variable names. Built-in catalog providers already carry this metadata for automatic environment-backed availability, and configured providers may need to declare the same source. For a configured provider this is additive metadata, not a requirement that one of the variables exists: the provider may instead be usable through configured options, a stored account, or an endpoint that needs no credential.
 
-Within configured models, rename legacy upstream model identifier `id` to `api_id` rather than exposing camelCase runtime `apiID`. Model `limit` is an authored patch, so an override may change only `context`, `input`, or `output`. Model `cost` accepts one simple pricing object or an array of tiered pricing entries; omitted cache prices default to zero.
+Within configured models, nest the legacy upstream model identifier `id` under `api.id` with the rest of the model API override. Model `limit` is an authored patch, so an override may change only `context`, `input`, or `output`. Model `cost` accepts one simple pricing object or an array of tiered pricing entries; omitted cache prices default to zero.
 
 Do not port legacy provider model `reasoning`, `temperature`, or `interleaved` flags as first-class config fields; provider/request behavior belongs in structured `options` or model variants. Do not port `release_date`, `status`, `experimental`, `whitelist`, or `blacklist` in this v2 surface.
 
@@ -223,7 +223,7 @@ Do not port legacy provider model `reasoning`, `temperature`, or `interleaved` f
       "options": { "headers": { "Authorization": "Bearer {env:API_KEY}" } },
       "models": {
         "chat": {
-          "api_id": "upstream-chat-model",
+          "api": { "id": "upstream-chat-model" },
           "limit": { "output": 32768 },
           "cost": { "input": 1.25, "output": 10 },
           "variants": [{ "id": "high", "aisdk": { "request": { "reasoningEffort": "high" } } }],