diff --git a/js/ai/src/prompt.ts b/js/ai/src/prompt.ts
index 373ce3bf0..d2f8a7603 100644
--- a/js/ai/src/prompt.ts
+++ b/js/ai/src/prompt.ts
@@ -17,9 +17,13 @@
 import { Action, defineAction, JSONSchema7 } from '@genkit-ai/core';
 import { lookupAction } from '@genkit-ai/core/registry';
 import z from 'zod';
-import { DocumentData } from './document';
-import { GenerateOptions } from './generate';
-import { GenerateRequest, GenerateRequestSchema, ModelArgument } from './model';
+import { DocumentData } from './document.js';
+import { GenerateOptions } from './generate.js';
+import {
+  GenerateRequest,
+  GenerateRequestSchema,
+  ModelArgument,
+} from './model.js';
 
 export type PromptFn<I extends z.ZodTypeAny = z.ZodTypeAny> = (
   input: z.infer<I>
diff --git a/js/ai/src/retriever.ts b/js/ai/src/retriever.ts
index f88514454..1ea4d9a4e 100644
--- a/js/ai/src/retriever.ts
+++ b/js/ai/src/retriever.ts
@@ -20,7 +20,14 @@ import * as z from 'zod';
 import { Document, DocumentData, DocumentDataSchema } from './document.js';
 import { EmbedderInfo } from './embedder.js';
 
-export { Document, DocumentData, DocumentDataSchema } from './document.js';
+export {
+  Document,
+  DocumentData,
+  DocumentDataSchema,
+  MediaPart,
+  Part,
+  TextPart,
+} from './document.js';
 
 type RetrieverFn<RetrieverOptions extends z.ZodTypeAny> = (
   query: Document,
diff --git a/js/core/src/reflectionApi.ts b/js/core/src/reflectionApi.ts
index 15bc547cf..aed10708c 100644
--- a/js/core/src/reflectionApi.ts
+++ b/js/core/src/reflectionApi.ts
@@ -21,8 +21,8 @@ import { config } from './config.js';
 import { logger } from './logging.js';
 import * as registry from './registry.js';
 import { toJsonSchema } from './schema.js';
-import { cleanUpTracing } from './tracing';
 import {
+  cleanUpTracing,
   flushTracing,
   newTrace,
   setCustomMetadataAttribute,
diff --git a/js/core/src/tracing.ts b/js/core/src/tracing.ts
index e4104c522..07dafd2a4 100644
--- a/js/core/src/tracing.ts
+++ b/js/core/src/tracing.ts
@@ -21,7 +21,7 @@ import {
   SpanProcessor,
 } from '@opentelemetry/sdk-trace-base';
 import { getCurrentEnv } from './config.js';
-import { logger } from './logging';
+import { logger } from './logging.js';
 import { TelemetryConfig } from './telemetryTypes.js';
 import { TraceStore } from './tracing.js';
 import { TraceStoreExporter } from './tracing/exporter.js';
diff --git a/js/plugins/dotprompt/src/metadata.ts b/js/plugins/dotprompt/src/metadata.ts
index fba380795..9073e860c 100644
--- a/js/plugins/dotprompt/src/metadata.ts
+++ b/js/plugins/dotprompt/src/metadata.ts
@@ -26,7 +26,7 @@ import {
 import { ToolArgument } from '@genkit-ai/ai/tool';
 import { JSONSchema, parseSchema, toJsonSchema } from '@genkit-ai/core/schema';
 import z from 'zod';
-import { picoschema } from './picoschema';
+import { picoschema } from './picoschema.js';
 
 /**
  * Metadata for a prompt.
diff --git a/js/plugins/evaluators/src/index.ts b/js/plugins/evaluators/src/index.ts
index 46a3d6eba..d26410428 100644
--- a/js/plugins/evaluators/src/index.ts
+++ b/js/plugins/evaluators/src/index.ts
@@ -30,7 +30,7 @@ import {
   faithfulnessScore,
   maliciousnessScore,
 } from './metrics';
-import { GenkitMetric } from './types';
+import { GenkitMetric } from './types.js';
 export { GenkitMetric };
 
 const PLUGIN_NAME = 'genkitEval';
diff --git a/js/plugins/evaluators/src/metrics/index.ts b/js/plugins/evaluators/src/metrics/index.ts
index 2ef7d1bcc..869a6e10c 100644
--- a/js/plugins/evaluators/src/metrics/index.ts
+++ b/js/plugins/evaluators/src/metrics/index.ts
@@ -14,6 +14,6 @@
  * limitations under the License.
  */
 
-export { answerRelevancyScore } from './answer_relevancy';
-export { faithfulnessScore } from './faithfulness';
-export { maliciousnessScore } from './maliciousness';
+export { answerRelevancyScore } from './answer_relevancy.js';
+export { faithfulnessScore } from './faithfulness.js';
+export { maliciousnessScore } from './maliciousness.js';
diff --git a/js/plugins/firebase/src/firestoreRetriever.ts b/js/plugins/firebase/src/firestoreRetriever.ts
index fd97ab128..b1c6fbc8d 100644
--- a/js/plugins/firebase/src/firestoreRetriever.ts
+++ b/js/plugins/firebase/src/firestoreRetriever.ts
@@ -15,7 +15,7 @@
  */
 
 import { embed, EmbedderArgument } from '@genkit-ai/ai/embedder';
-import { defineRetriever, DocumentData } from '@genkit-ai/ai/retriever';
+import { defineRetriever, DocumentData, Part } from '@genkit-ai/ai/retriever';
 import { VectorQuerySnapshot } from '@google-cloud/firestore';
 import {
   Firestore,
@@ -23,7 +23,6 @@ import {
   QueryDocumentSnapshot,
 } from 'firebase-admin/firestore';
 import z from 'zod';
-import { Part } from '../../../ai/lib/document';
 
 function toContent(
   d: QueryDocumentSnapshot,
diff --git a/js/plugins/google-cloud/src/gcpOpenTelemetry.ts b/js/plugins/google-cloud/src/gcpOpenTelemetry.ts
index ef74ebaac..756e4de81 100644
--- a/js/plugins/google-cloud/src/gcpOpenTelemetry.ts
+++ b/js/plugins/google-cloud/src/gcpOpenTelemetry.ts
@@ -40,7 +40,7 @@ import {
   ReadableSpan,
   SpanExporter,
 } from '@opentelemetry/sdk-trace-base';
-import { PluginOptions } from './index';
+import { PluginOptions } from './index.js';
 
 /**
  * Provides a {TelemetryConfig} for exporting OpenTelemetry data (Traces,
diff --git a/js/plugins/langchain/src/evaluators.ts b/js/plugins/langchain/src/evaluators.ts
index e8bc998c1..cf149db44 100644
--- a/js/plugins/langchain/src/evaluators.ts
+++ b/js/plugins/langchain/src/evaluators.ts
@@ -17,8 +17,8 @@
 import { BaseDataPointSchema, defineEvaluator } from '@genkit-ai/ai/evaluator';
 import { ModelArgument } from '@genkit-ai/ai/model';
 import { Criteria, loadEvaluator } from 'langchain/evaluation';
-import { genkitModel } from './model';
-import { GenkitTracer } from './tracing';
+import { genkitModel } from './model.js';
+import { GenkitTracer } from './tracing.js';
 
 export function langchainEvaluator(
   type: 'labeled_criteria' | 'criteria',
diff --git a/js/plugins/vertexai/src/embedder.ts b/js/plugins/vertexai/src/embedder.ts
index 79435f367..5de795b06 100644
--- a/js/plugins/vertexai/src/embedder.ts
+++ b/js/plugins/vertexai/src/embedder.ts
@@ -21,7 +21,7 @@ import {
 } from '@genkit-ai/ai/embedder';
 import { GoogleAuth } from 'google-auth-library';
 import { z } from 'zod';
-import { PluginOptions } from '.';
+import { PluginOptions } from './index.js';
 import { predictModel } from './predict.js';
 
 export const TaskTypeSchema = z.enum([
diff --git a/js/plugins/vertexai/src/evaluation.ts b/js/plugins/vertexai/src/evaluation.ts
index 39aeb6168..6a4de304c 100644
--- a/js/plugins/vertexai/src/evaluation.ts
+++ b/js/plugins/vertexai/src/evaluation.ts
@@ -17,7 +17,7 @@
 import { Action } from '@genkit-ai/core';
 import { GoogleAuth } from 'google-auth-library';
 import z from 'zod';
-import { EvaluatorFactory } from './evaluator_factory';
+import { EvaluatorFactory } from './evaluator_factory.js';
 
 /**
  * Vertex AI Evaluation metrics. See API documentation for more information.
diff --git a/js/plugins/vertexai/src/evaluator_factory.ts b/js/plugins/vertexai/src/evaluator_factory.ts
index ef8351c9e..2de3d3833 100644
--- a/js/plugins/vertexai/src/evaluator_factory.ts
+++ b/js/plugins/vertexai/src/evaluator_factory.ts
@@ -19,7 +19,7 @@ import { Action, GENKIT_CLIENT_HEADER } from '@genkit-ai/core';
 import { runInNewSpan } from '@genkit-ai/core/tracing';
 import { GoogleAuth } from 'google-auth-library';
 import z from 'zod';
-import { VertexAIEvaluationMetricType } from './evaluation';
+import { VertexAIEvaluationMetricType } from './evaluation.js';
 
 export class EvaluatorFactory {
   constructor(
diff --git a/js/plugins/vertexai/src/imagen.ts b/js/plugins/vertexai/src/imagen.ts
index 54aff6418..dd654f922 100644
--- a/js/plugins/vertexai/src/imagen.ts
+++ b/js/plugins/vertexai/src/imagen.ts
@@ -24,7 +24,7 @@ import {
 } from '@genkit-ai/ai/model';
 import { GoogleAuth } from 'google-auth-library';
 import z from 'zod';
-import { PluginOptions } from '.';
+import { PluginOptions } from './index.js';
 import { predictModel } from './predict.js';
 
 const ImagenConfigSchema = GenerationCommonConfigSchema.extend({
diff --git a/js/plugins/vertexai/src/index.ts b/js/plugins/vertexai/src/index.ts
index a8757b092..a1de76e4e 100644
--- a/js/plugins/vertexai/src/index.ts
+++ b/js/plugins/vertexai/src/index.ts
@@ -24,25 +24,25 @@ import {
   claude3Opus,
   claude3Sonnet,
   SUPPORTED_ANTHROPIC_MODELS,
-} from './anthropic';
+} from './anthropic.js';
 import {
   SUPPORTED_EMBEDDER_MODELS,
   textEmbeddingGecko,
   textEmbeddingGeckoEmbedder,
-} from './embedder';
+} from './embedder.js';
 import {
   VertexAIEvaluationMetric,
   VertexAIEvaluationMetricType,
   vertexEvaluators,
-} from './evaluation';
+} from './evaluation.js';
 import {
   gemini15ProPreview,
   geminiModel,
   geminiPro,
   geminiProVision,
   SUPPORTED_GEMINI_MODELS,
-} from './gemini';
-import { imagen2, imagen2Model } from './imagen';
+} from './gemini.js';
+import { imagen2, imagen2Model } from './imagen.js';
 
 export {
   claude3Haiku,