diff --git a/apis/cloudflare/package.json b/apis/cloudflare/package.json
index 8ca2f898..33eb2483 100644
--- a/apis/cloudflare/package.json
+++ b/apis/cloudflare/package.json
@@ -24,6 +24,6 @@
     "@opentelemetry/resources": "^1.18.1",
     "@opentelemetry/sdk-metrics": "^1.18.1",
     "dotenv": "^16.3.1",
-    "zod": "3.25.34"
+    "zod": "4.1.8"
   }
 }
diff --git a/package.json b/package.json
index 507dca31..808e545a 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,6 @@
   },
   "packageManager": "pnpm@8.15.5",
   "resolutions": {
-    "zod": "3.25.34"
+    "zod": "4.1.8"
   }
 }
diff --git a/packages/proxy/package.json b/packages/proxy/package.json
index 2cb5c127..a5955e68 100644
--- a/packages/proxy/package.json
+++ b/packages/proxy/package.json
@@ -110,6 +110,6 @@
     "jsonwebtoken": "^9.0.2",
     "openai": "4.104.0",
     "uuid": "^9.0.1",
-    "zod": "^3.25.34"
+    "zod": "4.1.8"
   }
 }
diff --git a/packages/proxy/schema/models.ts b/packages/proxy/schema/models.ts
index 1e0e8e08..d6f10d43 100644
--- a/packages/proxy/schema/models.ts
+++ b/packages/proxy/schema/models.ts
@@ -87,7 +87,9 @@ export const ModelSchema = z.object({
 export type ModelSpec = z.infer<typeof ModelSchema>;
 
 import modelListJson from "./model_list.json";
-const modelListJsonTyped = z.record(ModelSchema).parse(modelListJson);
+const modelListJsonTyped = z
+  .record(z.string(), ModelSchema)
+  .parse(modelListJson);
 
 // Because this file can be included and bundled in various ways, it's important to
 // really inject these variables into the global scope, rather than let the bundler
diff --git a/packages/proxy/schema/openai-realtime.ts b/packages/proxy/schema/openai-realtime.ts
index c1a64c38..f6e48c4c 100644
--- a/packages/proxy/schema/openai-realtime.ts
+++ b/packages/proxy/schema/openai-realtime.ts
@@ -29,7 +29,7 @@ export const toolDefinitionTypeSchema = z.object({
   type: z.literal("function").optional(),
   name: z.string(),
   description: z.string(),
-  parameters: z.record(z.unknown()),
+  parameters: z.record(z.string(), z.unknown()),
 });
 
 export const sessionResourceTypeSchema = z.object({
diff --git a/packages/proxy/schema/secrets.ts b/packages/proxy/schema/secrets.ts
index d5a9b401..aff3724a 100644
--- a/packages/proxy/schema/secrets.ts
+++ b/packages/proxy/schema/secrets.ts
@@ -4,7 +4,7 @@ import { ModelSchema } from "./models";
 export const BaseMetadataSchema = z
   .object({
     models: z.array(z.string()).nullish(),
-    customModels: z.record(ModelSchema).nullish(),
+    customModels: z.record(z.string(), ModelSchema).nullish(),
     excludeDefaultModels: z.boolean().nullish(),
     additionalHeaders: z.record(z.string(), z.string()).nullish(),
     supportsStreaming: z.boolean().default(true),
@@ -88,7 +88,7 @@ const APISecretBaseSchema = z
     org_name: z.string().nullish(),
     name: z.string().nullish(),
     secret: z.string(),
-    metadata: z.record(z.unknown()).nullish(),
+    metadata: z.record(z.string(), z.unknown()).nullish(),
   })
   .strict();
 
diff --git a/packages/proxy/src/generated_types.ts b/packages/proxy/src/generated_types.ts
index efb2aacf..d65fb5dc 100644
--- a/packages/proxy/src/generated_types.ts
+++ b/packages/proxy/src/generated_types.ts
@@ -517,7 +517,7 @@ export const ExperimentEvent = z.object({
   expected: z.unknown().optional(),
   error: z.unknown().optional(),
   scores: z
-    .union([z.record(z.union([z.number(), z.null()])), z.null()])
+    .union([z.record(z.string(), z.union([z.number(), z.null()])), z.null()])
     .optional(),
   metadata: z
     .union([
@@ -529,7 +529,7 @@ export const ExperimentEvent = z.object({
     ])
     .optional(),
   tags: z.union([z.array(z.string()), z.null()]).optional(),
-  metrics: z.union([z.record(z.number()), z.null()]).optional(),
+  metrics: z.union([z.record(z.string(), z.number()), z.null()]).optional(),
   context: z
     .union([
       z
@@ -648,7 +648,7 @@ export const PromptParserNullish = z.union([
   z.object({
     type: z.literal("llm_classifier"),
     use_cot: z.boolean(),
-    choice_scores: z.record(z.number().gte(0).lte(1)),
+    choice_scores: z.record(z.string(), z.number().gte(0).lte(1)),
   }),
   z.null(),
 ]);
@@ -770,8 +770,8 @@ export const GraphEdge = z.object({
 export type GraphEdgeType = z.infer<typeof GraphEdge>;
 export const GraphData = z.object({
   type: z.literal("graph"),
-  nodes: z.record(GraphNode),
-  edges: z.record(GraphEdge),
+  nodes: z.record(z.string(), GraphNode),
+  edges: z.record(z.string(), GraphEdge),
 });
 export type GraphDataType = z.infer<typeof GraphData>;
 export const FunctionData = z.union([
@@ -1122,7 +1122,7 @@ export const ProjectLogsEvent = z.object({
   expected: z.unknown().optional(),
   error: z.unknown().optional(),
   scores: z
-    .union([z.record(z.union([z.number(), z.null()])), z.null()])
+    .union([z.record(z.string(), z.union([z.number(), z.null()])), z.null()])
     .optional(),
   metadata: z
     .union([
@@ -1134,7 +1134,7 @@ export const ProjectLogsEvent = z.object({
     ])
     .optional(),
   tags: z.union([z.array(z.string()), z.null()]).optional(),
-  metrics: z.union([z.record(z.number()), z.null()]).optional(),
+  metrics: z.union([z.record(z.string(), z.number()), z.null()]).optional(),
   context: z
     .union([
       z
@@ -1173,7 +1173,7 @@ export const ProjectScoreCategory = z.object({
 export type ProjectScoreCategoryType = z.infer<typeof ProjectScoreCategory>;
 export const ProjectScoreCategories = z.union([
   z.array(ProjectScoreCategory),
-  z.record(z.number()),
+  z.record(z.string(), z.number()),
   z.array(z.string()),
   z.null(),
 ]);
@@ -1416,7 +1416,7 @@ export const ViewOptions = z.union([
         frameStart: z.union([z.string(), z.null()]),
         frameEnd: z.union([z.string(), z.null()]),
         tzUTC: z.union([z.boolean(), z.null()]),
-        chartVisibility: z.union([z.record(z.boolean()), z.null()]),
+        chartVisibility: z.union([z.record(z.string(), z.boolean()), z.null()]),
         projectId: z.union([z.string(), z.null()]),
         type: z.union([z.enum(["project", "experiment"]), z.null()]),
         groupBy: z.union([z.string(), z.null()]),
@@ -1425,9 +1425,9 @@ export const ViewOptions = z.union([
   }),
   z
     .object({
-      columnVisibility: z.union([z.record(z.boolean()), z.null()]),
+      columnVisibility: z.union([z.record(z.string(), z.boolean()), z.null()]),
       columnOrder: z.union([z.array(z.string()), z.null()]),
-      columnSizing: z.union([z.record(z.number()), z.null()]),
+      columnSizing: z.union([z.record(z.string(), z.number()), z.null()]),
       grouping: z.union([z.string(), z.null()]),
       rowHeight: z.union([z.string(), z.null()]),
       tallGroupRows: z.union([z.boolean(), z.null()]),
diff --git a/packages/proxy/types/anthropic.ts b/packages/proxy/types/anthropic.ts
index 7f2ff5f4..243af6f7 100644
--- a/packages/proxy/types/anthropic.ts
+++ b/packages/proxy/types/anthropic.ts
@@ -50,7 +50,7 @@ const anthropicToolUseContentPartSchema = z.object({
   type: z.literal("tool_use"),
   id: z.string(),
   name: z.string(),
-  input: z.record(z.any()),
+  input: z.record(z.string(), z.any()),
   cache_control: cacheControlSchema.optional(),
 });
 
@@ -58,7 +58,7 @@ const anthropicServerToolUseContentPartSchema = z.object({
   type: z.literal("server_tool_use"),
   id: z.string(),
   name: z.enum(["web_search", "code_execution"]),
-  input: z.record(z.any()),
+  input: z.record(z.string(), z.any()),
   cache_control: cacheControlSchema.optional(),
 });
 
@@ -128,7 +128,7 @@ const anthropicMCPToolUseContentPartSchema = z.object({
   type: z.literal("mcp_tool_use"),
   id: z.string(),
   name: z.string(),
-  input: z.record(z.any()),
+  input: z.record(z.string(), z.any()),
   server_name: z.string(),
   cache_control: cacheControlSchema.nullish(),
 });
@@ -144,7 +144,7 @@ const anthropicMCPToolResultContentPartSchema = z.object({
         type: z.literal("text"),
         text: z.string(),
         // This is a simplification of the strict citation schema
-        citations: z.array(z.record(z.any())).nullish(),
+        citations: z.array(z.record(z.string(), z.any())).nullish(),
         cache_control: cacheControlSchema.nullish(),
       }),
     ),
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 5081f92c..cda76796 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -5,7 +5,7 @@ settings:
   excludeLinksFromLockfile: false
 
 overrides:
-  zod: 3.25.34
+  zod: 4.1.8
 
 importers:
 
@@ -43,13 +43,13 @@ importers:
         version: 1.19.0(@opentelemetry/api@1.7.0)
       braintrust:
         specifier: ^0.3.7
-        version: 0.3.7(zod@3.25.34)
+        version: 0.3.7(zod@4.1.8)
       dotenv:
         specifier: ^16.3.1
         version: 16.3.1
       zod:
-        specifier: 3.25.34
-        version: 3.25.34
+        specifier: 4.1.8
+        version: 4.1.8
     devDependencies:
       '@cloudflare/workers-types':
         specifier: ^4.20241022.0
@@ -107,7 +107,7 @@ importers:
         version: 4.19.2
       openai:
         specifier: ^4.104.0
-        version: 4.104.0(zod@3.25.34)
+        version: 4.104.0(zod@4.1.8)
       redis:
         specifier: ^4.6.8
         version: 4.6.8
@@ -244,13 +244,13 @@ importers:
         version: 9.0.2
       openai:
         specifier: 4.104.0
-        version: 4.104.0(zod@3.25.34)
+        version: 4.104.0(zod@4.1.8)
       uuid:
         specifier: ^9.0.1
         version: 9.0.1
       zod:
-        specifier: 3.25.34
-        version: 3.25.34
+        specifier: 4.1.8
+        version: 4.1.8
     devDependencies:
       '@types/content-disposition':
         specifier: ^0.5.8
@@ -2274,8 +2274,8 @@ packages:
     dependencies:
       google-auth-library: 9.15.1
       ws: 8.18.0
-      zod: 3.25.34
-      zod-to-json-schema: 3.23.5(zod@3.25.34)
+      zod: 4.1.8
+      zod-to-json-schema: 3.23.5(zod@4.1.8)
     transitivePeerDependencies:
       - bufferutil
       - encoding
@@ -4395,14 +4395,14 @@ packages:
     resolution: {integrity: sha512-cZy8Dq+uuIXbxCZpuLd2GJdeSO/lIzIspC2WtkqIpje5QyFbvLaI5wZtdUjLHjGZrlVX6GilejatWwVYYRc8tA==}
     dev: false
 
-  /@zodios/core@10.9.6(axios@1.11.0)(zod@3.25.34):
+  /@zodios/core@10.9.6(axios@1.11.0)(zod@4.1.8):
     resolution: {integrity: sha512-aH4rOdb3AcezN7ws8vDgBfGboZMk2JGGzEq/DtW65MhnRxyTGRuLJRWVQ/2KxDgWvV2F5oTkAS+5pnjKbl0n+A==}
     peerDependencies:
       axios: ^0.x || ^1.0.0
-      zod: 3.25.34
+      zod: 4.1.8
     dependencies:
       axios: 1.11.0
-      zod: 3.25.34
+      zod: 4.1.8
     dev: true
 
   /abbrev@1.1.1:
@@ -4928,11 +4928,11 @@ packages:
       fill-range: 7.1.1
     dev: true
 
-  /braintrust@0.3.7(zod@3.25.34):
+  /braintrust@0.3.7(zod@4.1.8):
     resolution: {integrity: sha512-P6nJLgM98IOiBvAsgfUn9dbrLhmTfvED/+2ouacImTgs9adlZoGrIib9BkRAm+keSTfKLBPFqMmUi7QZ4ClemQ==}
     hasBin: true
     peerDependencies:
-      zod: 3.25.34
+      zod: 4.1.8
     dependencies:
       '@ai-sdk/provider': 1.1.3
       '@next/env': 14.2.3
@@ -4954,8 +4954,8 @@ packages:
       slugify: 1.6.6
       source-map: 0.7.4
       uuid: 9.0.1
-      zod: 3.25.34
-      zod-to-json-schema: 3.23.5(zod@3.25.34)
+      zod: 4.1.8
+      zod-to-json-schema: 3.23.5(zod@4.1.8)
     transitivePeerDependencies:
       - '@aws-sdk/credential-provider-web-identity'
       - supports-color
@@ -7950,7 +7950,7 @@ packages:
       workerd: 1.20250129.0
       ws: 8.18.0
       youch: 3.3.4
-      zod: 3.25.34
+      zod: 4.1.8
     transitivePeerDependencies:
       - bufferutil
       - utf-8-validate
@@ -8352,12 +8352,12 @@ packages:
       mimic-fn: 2.1.0
     dev: true
 
-  /openai@4.104.0(zod@3.25.34):
+  /openai@4.104.0(zod@4.1.8):
     resolution: {integrity: sha512-p99EFNsA/yX6UhVO93f5kJsDRLAg+CTA2RBqdHK4RtK8u5IJw32Hyb2dTGKbnnFmnuoBv5r7Z2CURI9sGZpSuA==}
     hasBin: true
     peerDependencies:
       ws: ^8.18.0
-      zod: 3.25.34
+      zod: 4.1.8
     peerDependenciesMeta:
       ws:
         optional: true
@@ -8371,7 +8371,7 @@ packages:
       form-data-encoder: 1.7.2
       formdata-node: 4.4.1
       node-fetch: 2.7.0
-      zod: 3.25.34
+      zod: 4.1.8
     transitivePeerDependencies:
       - encoding
     dev: false
@@ -8386,7 +8386,7 @@ packages:
     dependencies:
       '@apidevtools/swagger-parser': 10.1.1(openapi-types@12.1.3)
       '@liuli-util/fs-extra': 0.1.0
-      '@zodios/core': 10.9.6(axios@1.11.0)(zod@3.25.34)
+      '@zodios/core': 10.9.6(axios@1.11.0)(zod@4.1.8)
       axios: 1.11.0
       cac: 6.7.14
       handlebars: 4.7.8
@@ -8397,7 +8397,7 @@ packages:
       tanu: 0.1.13
       ts-pattern: 5.8.0
       whence: 2.1.0
-      zod: 3.25.34
+      zod: 4.1.8
     transitivePeerDependencies:
       - debug
       - react
@@ -11036,16 +11036,16 @@ packages:
       stacktracey: 2.1.8
     dev: true
 
-  /zod-to-json-schema@3.23.5(zod@3.25.34):
+  /zod-to-json-schema@3.23.5(zod@4.1.8):
     resolution: {integrity: sha512-5wlSS0bXfF/BrL4jPAbz9da5hDlDptdEppYfe+x4eIJ7jioqKG9uUxOwPzqof09u/XeVdrgFu29lZi+8XNDJtA==}
     peerDependencies:
-      zod: 3.25.34
+      zod: 4.1.8
     dependencies:
-      zod: 3.25.34
+      zod: 4.1.8
     dev: false
 
-  /zod@3.25.34:
-    resolution: {integrity: sha512-lZHvSc2PpWdcfpHlyB33HA9nqP16GpC9IpiG4lYq9jZCJVLZNnWd6Y1cj79bcLSBKTkxepfpjckPv5Y5VOPlwA==}
+  /zod@4.1.8:
+    resolution: {integrity: sha512-5R1P+WwQqmmMIEACyzSvo4JXHY5WiAFHRMg+zBZKgKS+Q1viRa0C1hmUKtHltoIFKtIdki3pRxkmpP74jnNYHQ==}
 
   github.com/openai/openai-realtime-api-beta/cd8a9251dcfb0cba0d7b0501e9ff36c915f5090f:
     resolution: {tarball: https://codeload.github.com/openai/openai-realtime-api-beta/tar.gz/cd8a9251dcfb0cba0d7b0501e9ff36c915f5090f}