feat: support extension of AiSDKRunner

```ts
// env.config.mjs
...

class OllamaCustomExecutor extend AiSdkRunner {
  override getAiSdkModelOptions(request: LocalLlmGenerateTextRequestOptions): Promise<AiSdkModelOptions> {
     if (<.. model is your custom one>) {
        ...
     }
     return super.getAiSdkModelOptions(request);
  }

}

executor = new LocalExecutor({config}, new OllamaCustomExecutor())
```

Fixes #221

Author: devversion

runner/codegen/ai-sdk/ai-sdk-model-options.ts

@@ -1,12 +1,14 @@
 import {AnthropicProviderOptions} from '@ai-sdk/anthropic';
 import {GoogleGenerativeAIProviderOptions} from '@ai-sdk/google';
 import {OpenAIResponsesProviderOptions} from '@ai-sdk/openai';
-import {LanguageModelV3} from '@ai-sdk/provider';
+import {LanguageModelV3, SharedV3ProviderOptions} from '@ai-sdk/provider';
 
-export type ModelOptions = {
+export type AiSdkModelOptions = {
   model: LanguageModelV3;
   providerOptions:
     | {anthropic: AnthropicProviderOptions}
     | {google: GoogleGenerativeAIProviderOptions}
-    | {openai: OpenAIResponsesProviderOptions};
+    | {openai: OpenAIResponsesProviderOptions}
+    // This supports extensions of `AISdkRunner` for custom model providers.
+    | SharedV3ProviderOptions;
 };

runner/codegen/ai-sdk/ai-sdk-runner.ts

@@ -26,6 +26,7 @@ import {
 import {ANTHROPIC_MODELS, getAiSdkModelOptionsForAnthropic} from './anthropic.js';
 import {getAiSdkModelOptionsForGoogle, GOOGLE_MODELS} from './google.js';
 import {getAiSdkModelOptionsForOpenAI, OPENAI_MODELS} from './openai.js';
+import {AiSdkModelOptions} from './ai-sdk-model-options.js';
 
 const SUPPORTED_MODELS = [...GOOGLE_MODELS, ...ANTHROPIC_MODELS, ...OPENAI_MODELS] as const;
 
@@ -34,7 +35,7 @@ const SUPPORTED_MODELS = [...GOOGLE_MODELS, ...ANTHROPIC_MODELS, ...OPENAI_MODEL
 // even if it involves many exponential backoff-waiting.
 const DEFAULT_MAX_RETRIES = 100000;
 
-export class AiSDKRunner implements LlmRunner {
+export class AiSdkRunner implements LlmRunner {
   displayName = 'AI SDK';
   id = 'ai-sdk';
   hasBuiltInRepairLoop = true;
@@ -44,9 +45,9 @@ export class AiSDKRunner implements LlmRunner {
   ): Promise<LocalLlmGenerateTextResponse> {
     const response = await this._wrapRequestWithTimeoutAndRateLimiting(options, async abortSignal =>
       generateText({
-        ...(await this._getAiSdkModelOptions(options)),
+        ...(await this.getAiSdkModelOptions(options)),
         abortSignal: abortSignal,
-        messages: this._convertRequestToMessagesList(options),
+        messages: this.convertRequestToMessagesList(options),
         maxRetries: DEFAULT_MAX_RETRIES,
       }),
     );
@@ -69,8 +70,8 @@ export class AiSDKRunner implements LlmRunner {
   ): Promise<LocalLlmConstrainedOutputGenerateResponse<T>> {
     const response = await this._wrapRequestWithTimeoutAndRateLimiting(options, async abortSignal =>
       generateText({
-        ...(await this._getAiSdkModelOptions(options)),
-        messages: this._convertRequestToMessagesList(options),
+        ...(await this.getAiSdkModelOptions(options)),
+        messages: this.convertRequestToMessagesList(options),
         output: Output.object<z.infer<T>>({schema: options.schema}),
         abortSignal: abortSignal,
         maxRetries: DEFAULT_MAX_RETRIES,
@@ -138,13 +139,9 @@ export class AiSDKRunner implements LlmRunner {
     );
   }
 
-  private async _getAiSdkModelOptions(request: LocalLlmGenerateTextRequestOptions): Promise<{
-    model: LanguageModel;
-    providerOptions:
-      | {anthropic: AnthropicProviderOptions}
-      | {google: GoogleGenerativeAIProviderOptions}
-      | {openai: OpenAIResponsesProviderOptions};
-  }> {
+  protected async getAiSdkModelOptions(
+    request: LocalLlmGenerateTextRequestOptions,
+  ): Promise<AiSdkModelOptions> {
     const result =
       (await getAiSdkModelOptionsForGoogle(request.model)) ??
       (await getAiSdkModelOptionsForAnthropic(request.model)) ??
@@ -155,7 +152,7 @@ export class AiSDKRunner implements LlmRunner {
     return result;
   }
 
-  private _convertRequestToMessagesList(
+  protected convertRequestToMessagesList(
     request: LocalLlmConstrainedOutputGenerateRequestOptions | LocalLlmGenerateTextRequestOptions,
   ): ModelMessage[] {
     return [
@@ -169,13 +166,13 @@ export class AiSDKRunner implements LlmRunner {
           ]
         : []),
       // Optional additional messages
-      ...this._toAiSDKMessage(request.messages ?? []),
+      ...this.toAiSDKMessage(request.messages ?? []),
       // The main message.
       {role: 'user', content: [{type: 'text', text: request.prompt}]},
     ];
   }
 
-  private _toAiSDKMessage(messages: PromptDataMessage[]): ModelMessage[] {
+  protected toAiSDKMessage(messages: PromptDataMessage[]): ModelMessage[] {
     const result: ModelMessage[] = [];
 
     for (const message of messages) {

runner/codegen/ai-sdk/anthropic.ts

@@ -1,7 +1,7 @@
 import {anthropic, AnthropicProviderOptions} from '@ai-sdk/anthropic';
 import {wrapLanguageModel} from 'ai';
 import {anthropicThinkingWithStructuredResponseMiddleware} from './anthropic_thinking_patch.js';
-import {ModelOptions} from './ai-sdk-model-options.js';
+import {AiSdkModelOptions} from './ai-sdk-model-options.js';
 
 export const ANTHROPIC_MODELS = [
   'claude-opus-4.1-no-thinking',
@@ -17,7 +17,7 @@ export const ANTHROPIC_MODELS = [
 
 export async function getAiSdkModelOptionsForAnthropic(
   rawModelName: string,
-): Promise<ModelOptions | null> {
+): Promise<AiSdkModelOptions | null> {
   const modelName = rawModelName as (typeof ANTHROPIC_MODELS)[number];
 
   switch (modelName) {

runner/codegen/ai-sdk/google.ts

@@ -1,5 +1,5 @@
 import {google, GoogleGenerativeAIProviderOptions} from '@ai-sdk/google';
-import {ModelOptions} from './ai-sdk-model-options.js';
+import {AiSdkModelOptions} from './ai-sdk-model-options.js';
 
 export const GOOGLE_MODELS = [
   'gemini-2.5-flash-lite',
@@ -13,7 +13,7 @@ export const GOOGLE_MODELS = [
 
 export async function getAiSdkModelOptionsForGoogle(
   rawModelName: string,
-): Promise<ModelOptions | null> {
+): Promise<AiSdkModelOptions | null> {
   const modelName = rawModelName as (typeof GOOGLE_MODELS)[number];
 
   switch (modelName) {

runner/codegen/ai-sdk/openai.ts

@@ -1,5 +1,5 @@
 import {openai, OpenAIResponsesProviderOptions} from '@ai-sdk/openai';
-import {ModelOptions} from './ai-sdk-model-options.js';
+import {AiSdkModelOptions} from './ai-sdk-model-options.js';
 
 export const OPENAI_MODELS = [
   'gpt-5.1-no-thinking',
@@ -10,7 +10,7 @@ export const OPENAI_MODELS = [
 
 export async function getAiSdkModelOptionsForOpenAI(
   rawModelName: string,
-): Promise<ModelOptions | null> {
+): Promise<AiSdkModelOptions | null> {
   const modelName = rawModelName as (typeof OPENAI_MODELS)[number];
 
   switch (modelName) {

runner/codegen/runner-creation.ts

@@ -4,11 +4,11 @@ import type {ClaudeCodeRunner} from './claude-code-runner.js';
 import type {GenkitRunner} from './genkit/genkit-runner.js';
 import type {CodexRunner} from './codex-runner.js';
 import type {NoopUnimplementedRunner} from './noop-unimplemented-runner.js';
-import {AiSDKRunner} from './ai-sdk/ai-sdk-runner.js';
+import {AiSdkRunner} from './ai-sdk/ai-sdk-runner.js';
 
 interface AvailableRunners {
   genkit: GenkitRunner;
-  'ai-sdk': AiSDKRunner;
+  'ai-sdk': AiSdkRunner;
   'gemini-cli': GeminiCliRunner;
   'claude-code': ClaudeCodeRunner;
   'codex': CodexRunner;
@@ -31,7 +31,7 @@ export async function getRunnerByName<T extends RunnerName>(name: T): Promise<Av
       );
     case 'ai-sdk':
       return import('./ai-sdk/ai-sdk-runner.js').then(
-        m => new m.AiSDKRunner() as AvailableRunners[T],
+        m => new m.AiSdkRunner() as AvailableRunners[T],
       );
     case 'gemini-cli':
       return import('./gemini-cli-runner.js').then(

runner/index.ts

@@ -52,3 +52,5 @@ export {replaceAtReferencesInPrompt} from './utils/prompt-at-references.js';
 export {extractRubrics} from './utils/extract-rubrics.js';
 export {combineReports} from './utils/combine-reports.mjs';
 export {writeReportToDisk} from './reporting/report-logging.js';
+export {AiSdkRunner} from './codegen/ai-sdk/ai-sdk-runner.js';
+export {type AiSdkModelOptions as AiSDKModelOptions} from './codegen/ai-sdk/ai-sdk-model-options.js';

runner/orchestration/executors/local-executor.ts

@@ -36,9 +36,12 @@ export class LocalExecutor implements Executor {
 
   constructor(
     public config: LocalExecutorConfig,
-    runnerName: RunnerName = 'noop-unimplemented',
+    runnerOrName: RunnerName | LlmRunner = 'noop-unimplemented',
   ) {
-    this.llm = getRunnerByName(runnerName);
+    this.llm =
+      typeof runnerOrName === 'string'
+        ? getRunnerByName(runnerOrName)
+        : Promise.resolve(runnerOrName);
   }
 
   async initializeEval(_prompt: RootPromptDefinition): Promise<EvalID> {