diff --git a/prisma/migrations/20230718005301_add_gpt4_eval_type/migration.sql b/prisma/migrations/20230718005301_add_gpt4_eval_type/migration.sql
new file mode 100644
index 0000000..abbbafd
--- /dev/null
+++ b/prisma/migrations/20230718005301_add_gpt4_eval_type/migration.sql
@@ -0,0 +1,39 @@
+/*
+  Warnings:
+
+  - You are about to drop the `EvaluationResult` table. If the table is not empty, all the data it contains will be lost.
+
+*/
+-- AlterEnum
+ALTER TYPE "EvalType" ADD VALUE 'GPT4_EVAL';
+
+-- DropForeignKey
+ALTER TABLE "EvaluationResult" DROP CONSTRAINT "EvaluationResult_evaluationId_fkey";
+
+-- DropForeignKey
+ALTER TABLE "EvaluationResult" DROP CONSTRAINT "EvaluationResult_promptVariantId_fkey";
+
+-- DropTable
+DROP TABLE "EvaluationResult";
+
+-- CreateTable
+CREATE TABLE "OutputEvaluation" (
+    "id" UUID NOT NULL,
+    "result" DOUBLE PRECISION NOT NULL,
+    "details" TEXT,
+    "modelOutputId" UUID NOT NULL,
+    "evaluationId" UUID NOT NULL,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "OutputEvaluation_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "OutputEvaluation_modelOutputId_evaluationId_key" ON "OutputEvaluation"("modelOutputId", "evaluationId");
+
+-- AddForeignKey
+ALTER TABLE "OutputEvaluation" ADD CONSTRAINT "OutputEvaluation_modelOutputId_fkey" FOREIGN KEY ("modelOutputId") REFERENCES "ModelOutput"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "OutputEvaluation" ADD CONSTRAINT "OutputEvaluation_evaluationId_fkey" FOREIGN KEY ("evaluationId") REFERENCES "Evaluation"("id") ON DELETE CASCADE ON UPDATE CASCADE;
diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index 119a78d..e8f8ea7 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -132,6 +132,7 @@ model ModelOutput {
 enum EvalType {
     CONTAINS
     DOES_NOT_CONTAIN
+    GPT4_EVAL
 }
 
 model Evaluation {
diff --git a/src/components/AutoResizeTextArea.tsx b/src/components/AutoResizeTextArea.tsx
index 54ec2e1..ac0e25a 100644
--- a/src/components/AutoResizeTextArea.tsx
+++ b/src/components/AutoResizeTextArea.tsx
@@ -4,7 +4,7 @@ import React from "react";
 
 export const AutoResizeTextarea: React.ForwardRefRenderFunction<
   HTMLTextAreaElement,
-  TextareaProps
+  TextareaProps & { minRows?: number }
 > = (props, ref) => {
   return (
     <Textarea
diff --git a/src/components/OutputsTable/EditEvaluations.tsx b/src/components/OutputsTable/EditEvaluations.tsx
index a672064..0028391 100644
--- a/src/components/OutputsTable/EditEvaluations.tsx
+++ b/src/components/OutputsTable/EditEvaluations.tsx
@@ -11,12 +11,14 @@ import {
   FormLabel,
   Select,
   FormHelperText,
+  Code,
 } from "@chakra-ui/react";
 import { type Evaluation, EvalType } from "@prisma/client";
 import { useCallback, useState } from "react";
 import { BsPencil, BsX } from "react-icons/bs";
 import { api } from "~/utils/api";
 import { useExperiment, useHandledAsyncCallback } from "~/utils/hooks";
+import AutoResizeTextArea from "../AutoResizeTextArea";
 
 type EvalValues = Pick<Evaluation, "label" | "value" | "evalType">;
 
@@ -36,7 +38,7 @@ export function EvaluationEditor(props: {
     <VStack borderTopWidth={1} borderColor="gray.200" py={4}>
       <HStack w="100%">
         <FormControl flex={1}>
-          <FormLabel fontSize="sm">Evaluation Name</FormLabel>
+          <FormLabel fontSize="sm">Eval Name</FormLabel>
           <Input
             size="sm"
             value={values.label}
@@ -44,7 +46,7 @@ export function EvaluationEditor(props: {
           />
         </FormControl>
         <FormControl flex={1}>
-          <FormLabel fontSize="sm">Match Type</FormLabel>
+          <FormLabel fontSize="sm">Eval Type</FormLabel>
           <Select
             size="sm"
             value={values.evalType}
@@ -63,17 +65,37 @@ export function EvaluationEditor(props: {
           </Select>
         </FormControl>
       </HStack>
-      <FormControl>
-        <FormLabel fontSize="sm">Match String</FormLabel>
-        <Input
-          size="sm"
-          value={values.value}
-          onChange={(e) => setValues((values) => ({ ...values, value: e.target.value }))}
-        />
-        <FormHelperText>
-          This string will be interpreted as a regex and checked against each model output.
-        </FormHelperText>
-      </FormControl>
+      {["CONTAINS", "DOES_NOT_CONTAIN"].includes(values.evalType) && (
+        <FormControl>
+          <FormLabel fontSize="sm">Match String</FormLabel>
+          <Input
+            size="sm"
+            value={values.value}
+            onChange={(e) => setValues((values) => ({ ...values, value: e.target.value }))}
+          />
+          <FormHelperText>
+            This string will be interpreted as a regex and checked against each model output. You
+            can include scenario variables using <Code>{"{{curly_braces}}"}</Code>
+          </FormHelperText>
+        </FormControl>
+      )}
+      {values.evalType === "GPT4_EVAL" && (
+        <FormControl pt={2}>
+          <FormLabel fontSize="sm">GPT4 Instructions</FormLabel>
+          <AutoResizeTextArea
+            size="sm"
+            value={values.value}
+            onChange={(e) => setValues((values) => ({ ...values, value: e.target.value }))}
+            minRows={3}
+          />
+          <FormHelperText>
+            Give instructions to GPT-4 for how to evaluate your prompt. It will have access to the
+            full scenario as well as the output it is evaluating. It will <strong>not</strong> have
+            access to the specific prompt variant, so be sure to be clear about the task you want it
+            to perform.
+          </FormHelperText>
+        </FormControl>
+      )}
       <HStack alignSelf="flex-end">
         <Button size="sm" onClick={props.onCancel} colorScheme="gray">
           Cancel
diff --git a/src/components/OutputsTable/EditScenarioVars.tsx b/src/components/OutputsTable/EditScenarioVars.tsx
index 1e912d7..97a359c 100644
--- a/src/components/OutputsTable/EditScenarioVars.tsx
+++ b/src/components/OutputsTable/EditScenarioVars.tsx
@@ -1,4 +1,4 @@
-import { Text, Button, HStack, Heading, Icon, Input, Stack, Code } from "@chakra-ui/react";
+import { Text, Button, HStack, Heading, Icon, Input, Stack } from "@chakra-ui/react";
 import { useState } from "react";
 import { BsCheck, BsX } from "react-icons/bs";
 import { api } from "~/utils/api";
@@ -36,8 +36,7 @@ export default function EditScenarioVars() {
       <Heading size="sm">Scenario Variables</Heading>
       <Stack spacing={2}>
         <Text fontSize="sm">
-          Scenario variables can be used in your prompt variants as well as evaluations. Reference
-          them using <Code>{"{{curly_braces}}"}</Code>.
+          Scenario variables can be used in your prompt variants as well as evaluations.
         </Text>
         <HStack spacing={0}>
           <Input
diff --git a/src/components/OutputsTable/OutputCell/OutputStats.tsx b/src/components/OutputsTable/OutputCell/OutputStats.tsx
index 5256168..3f511df 100644
--- a/src/components/OutputsTable/OutputCell/OutputStats.tsx
+++ b/src/components/OutputsTable/OutputCell/OutputStats.tsx
@@ -2,7 +2,7 @@ import { type SupportedModel } from "~/server/types";
 import { type Scenario } from "../types";
 import { type RouterOutputs } from "~/utils/api";
 import { calculateTokenCost } from "~/utils/calculateTokenCost";
-import { HStack, Icon, Text } from "@chakra-ui/react";
+import { HStack, Icon, Text, Tooltip } from "@chakra-ui/react";
 import { BsCheck, BsClock, BsCurrencyDollar, BsX } from "react-icons/bs";
 import { CostTooltip } from "~/components/tooltip/CostTooltip";
 
@@ -36,14 +36,20 @@ export const OutputStats = ({
         {modelOutput.outputEvaluation.map((evaluation) => {
           const passed = evaluation.result > 0.5;
           return (
-            <HStack spacing={0} key={evaluation.id}>
-              <Text>{evaluation.evaluation.label}</Text>
-              <Icon
-                as={passed ? BsCheck : BsX}
-                color={passed ? "green.500" : "red.500"}
-                boxSize={6}
-              />
-            </HStack>
+            <Tooltip
+              isDisabled={!evaluation.details}
+              label={evaluation.details}
+              key={evaluation.id}
+            >
+              <HStack spacing={0}>
+                <Text>{evaluation.evaluation.label}</Text>
+                <Icon
+                  as={passed ? BsCheck : BsX}
+                  color={passed ? "green.500" : "red.500"}
+                  boxSize={6}
+                />
+              </HStack>
+            </Tooltip>
           );
         })}
       </HStack>
diff --git a/src/server/utils/evaluations.ts b/src/server/utils/evaluations.ts
index 8740b88..8d82582 100644
--- a/src/server/utils/evaluations.ts
+++ b/src/server/utils/evaluations.ts
@@ -4,7 +4,7 @@ import { runOneEval } from "./runOneEval";
 import { type Scenario } from "~/components/OutputsTable/types";
 
 const saveResult = async (evaluation: Evaluation, scenario: Scenario, modelOutput: ModelOutput) => {
-  const result = runOneEval(evaluation, scenario, modelOutput);
+  const result = await runOneEval(evaluation, scenario, modelOutput);
   return await prisma.outputEvaluation.upsert({
     where: {
       modelOutputId_evaluationId: {
@@ -15,10 +15,10 @@ const saveResult = async (evaluation: Evaluation, scenario: Scenario, modelOutpu
     create: {
       modelOutputId: modelOutput.id,
       evaluationId: evaluation.id,
-      result,
+      ...result,
     },
     update: {
-      result,
+      ...result,
     },
   });
 };
@@ -35,43 +35,6 @@ export const runEvalsForOutput = async (
   await Promise.all(
     evaluations.map(async (evaluation) => await saveResult(evaluation, scenario, modelOutput)),
   );
-
-  // const cells = await prisma.scenarioVariantCell.findMany({
-  //   where: {
-  //     promptVariantId: variantId,
-  //     retrievalStatus: "COMPLETE",
-  //     testScenario: { visible: true },
-  //   },
-  //   include: { testScenario: true, modelOutput: { include: { OutputEvaluation: true } } },
-  // });
-
-  // await Promise.all(
-  //   evaluations.map(async (evaluation) => {
-  //     const passCount = cells.filter((cell) =>
-  //       runOneEval(cell.modelOutput as ModelOutput, cell.testScenario, evaluation),
-  //     ).length;
-  //     const failCount = cells.length - passCount;
-
-  //     await prisma.evaluationResult.upsert({
-  //       where: {
-  //         evaluationId_promptVariantId: {
-  //           evaluationId: evaluation.id,
-  //           promptVariantId: variantId,
-  //         },
-  //       },
-  //       create: {
-  //         evaluationId: evaluation.id,
-  //         promptVariantId: variantId,
-  //         passCount,
-  //         failCount,
-  //       },
-  //       update: {
-  //         passCount,
-  //         failCount,
-  //       },
-  //     });
-  //   }),
-  // );
 };
 
 export const runAllEvals = async (experimentId: string) => {
@@ -113,42 +76,4 @@ export const runAllEvals = async (experimentId: string) => {
       );
     }),
   );
-
-  // const cells = await prisma.scenarioVariantCell.findMany({
-  //   where: {
-  //     promptVariantId: { in: variants.map((v) => v.id) },
-  //     testScenario: { visible: true },
-  //     statusCode: { notIn: [429] },
-  //   },
-  //   include: { testScenario: true, modelOutput: true },
-  // });
-
-  // await Promise.all(
-  //   variants.map(async (variant) => {
-  //     const variantCells = cells.filter((cell) => cell.promptVariantId === variant.id);
-  //     const passCount = variantCells.filter((cell) =>
-  //       runOneEval(cell.modelOutput as ModelOutput, cell.testScenario, evaluation),
-  //     ).length;
-  //     const failCount = variantCells.length - passCount;
-
-  //     await prisma.evaluationResult.upsert({
-  //       where: {
-  //         evaluationId_promptVariantId: {
-  //           evaluationId: evaluation.id,
-  //           promptVariantId: variant.id,
-  //         },
-  //       },
-  //       create: {
-  //         evaluationId: evaluation.id,
-  //         promptVariantId: variant.id,
-  //         passCount,
-  //         failCount,
-  //       },
-  //       update: {
-  //         passCount,
-  //         failCount,
-  //       },
-  //     });
-  //   }),
-  // );
 };
diff --git a/src/server/utils/runOneEval.ts b/src/server/utils/runOneEval.ts
index 619f271..54c8960 100644
--- a/src/server/utils/runOneEval.ts
+++ b/src/server/utils/runOneEval.ts
@@ -1,32 +1,93 @@
 import { type Evaluation, type ModelOutput, type TestScenario } from "@prisma/client";
 import { type ChatCompletion } from "openai/resources/chat";
 import { type VariableMap, fillTemplate } from "./fillTemplate";
+import { openai } from "./openai";
+import dedent from "dedent";
 
-export const runOneEval = (
+export const runGpt4Eval = async (
+  evaluation: Evaluation,
+  scenario: TestScenario,
+  message: ChatCompletion.Choice.Message,
+): Promise<{ result: number; details: string }> => {
+  const output = await openai.chat.completions.create({
+    model: "gpt-4-0613",
+    messages: [
+      {
+        role: "system",
+        content: dedent`
+        You are a highly intelligent AI model and have been tasked with evaluating the quality of a simpler model. Your objective is to determine whether the simpler model has produced a successful and correct output. You should return "true" if the output was successful and "false" if it was not. Pay more attention to the semantics of the output than the formatting. Success is defined in the following terms:
+        ---
+        ${evaluation.value}
+        `,
+      },
+      {
+        role: "user",
+        content: `Scenario:\n---\n${JSON.stringify(scenario.variableValues, null, 2)}`,
+      },
+      {
+        role: "user",
+        content: `The full output of the simpler message:\n---\n${JSON.stringify(
+          message.content ?? message.function_call,
+          null,
+          2,
+        )}`,
+      },
+    ],
+    function_call: {
+      name: "report_success",
+    },
+    functions: [
+      {
+        name: "report_success",
+        parameters: {
+          type: "object",
+          required: ["thoughts", "success"],
+          properties: {
+            thoughts: {
+              type: "string",
+              description: "Explain your reasoning for considering this a pass or fail",
+            },
+            success: {
+              type: "boolean",
+              description:
+                "Whether the simpler model successfully completed the task for this scenario",
+            },
+          },
+        },
+      },
+    ],
+  });
+
+  try {
+    const out = JSON.parse(output.choices[0]?.message?.function_call?.arguments ?? "");
+    return { result: out.success ? 1 : 0, details: out.thoughts ?? JSON.stringify(out) };
+  } catch (e) {
+    console.error(e);
+    return { result: 0, details: "Error parsing GPT-4 output" };
+  }
+};
+
+export const runOneEval = async (
   evaluation: Evaluation,
   scenario: TestScenario,
   modelOutput: ModelOutput,
-): number => {
+): Promise<{ result: number; details?: string }> => {
   const output = modelOutput.output as unknown as ChatCompletion;
 
   const message = output?.choices?.[0]?.message;
 
-  if (!message) return 0;
+  if (!message) return { result: 0 };
 
   const stringifiedMessage = message.content ?? JSON.stringify(message.function_call);
 
   const matchRegex = fillTemplate(evaluation.value, scenario.variableValues as VariableMap);
 
-  let result;
-
   switch (evaluation.evalType) {
     case "CONTAINS":
-      result = stringifiedMessage.match(matchRegex) !== null ? 1 : 0;
-      break;
+      return { result: stringifiedMessage.match(matchRegex) !== null ? 1 : 0 };
     case "DOES_NOT_CONTAIN":
-      result = stringifiedMessage.match(matchRegex) === null ? 1 : 0;
-      break;
+      return { result: stringifiedMessage.match(matchRegex) === null ? 1 : 0 };
+    case "GPT4_EVAL":
+      return await runGpt4Eval(evaluation, scenario, message);
   }
-
-  return result;
 };