fix: add automatic caching for anthropic (#12743)

jaderiverstokes · gr2m · claude · web-flow · commit 17978c667502 · 2026-02-24T14:48:11.000-08:00
## Background Anthropic now supports automatic caching. The top level provider options supports it already, however it gets stripped before being sent to the provider. ## Summary Pass the cacheControl flag through the provider. ## Manual Verification Adds unit test. ## Checklist - [X] Tests have been added / updated (for bug fixes / features) - [ ] Documentation has been added / updated (for bug fixes / features) - [ ] A _patch_ changeset for relevant packages has been added (for bug fixes / features - run `pnpm changeset` in the project root) - [X] I have reviewed this pull request (self-review) ## Related Issues Fixes #12712 --------- Co-authored-by: Gregor Martynus <39992+gr2m@users.noreply.github.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
diff --git a/.changeset/add-automatic-caching-anthropic.md b/.changeset/add-automatic-caching-anthropic.md
@@ -0,0 +1,5 @@
+---
+'@ai-sdk/anthropic': patch
+---
+
+Pass `cacheControl` provider option as top-level `cache_control` in Anthropic API request body to support automatic caching.
diff --git a/packages/anthropic/src/anthropic-messages-language-model.test.ts b/packages/anthropic/src/anthropic-messages-language-model.test.ts
@@ -4168,6 +4168,79 @@ describe('AnthropicMessagesLanguageModel', () => {
       expect(result.warnings).toStrictEqual([]);
     });
 
+    it('should pass cache_control to request body', async () => {
+      prepareJsonFixtureResponse('anthropic-text');
+
+      const result = await model.doGenerate({
+        prompt: TEST_PROMPT,
+        providerOptions: {
+          anthropic: {
+            cacheControl: { type: 'ephemeral' },
+          } satisfies AnthropicLanguageModelOptions,
+        },
+      });
+
+      expect(await server.calls[0].requestBodyJson).toMatchInlineSnapshot(`
+        {
+          "cache_control": {
+            "type": "ephemeral",
+          },
+          "max_tokens": 4096,
+          "messages": [
+            {
+              "content": [
+                {
+                  "text": "Hello",
+                  "type": "text",
+                },
+              ],
+              "role": "user",
+            },
+          ],
+          "model": "claude-3-haiku-20240307",
+        }
+      `);
+
+      expect(result.warnings).toStrictEqual([]);
+    });
+
+    it('should pass cache_control with ttl to request body', async () => {
+      prepareJsonFixtureResponse('anthropic-text');
+
+      const result = await model.doGenerate({
+        prompt: TEST_PROMPT,
+        providerOptions: {
+          anthropic: {
+            cacheControl: { type: 'ephemeral', ttl: '1h' },
+          } satisfies AnthropicLanguageModelOptions,
+        },
+      });
+
+      expect(await server.calls[0].requestBodyJson).toMatchInlineSnapshot(`
+        {
+          "cache_control": {
+            "ttl": "1h",
+            "type": "ephemeral",
+          },
+          "max_tokens": 4096,
+          "messages": [
+            {
+              "content": [
+                {
+                  "text": "Hello",
+                  "type": "text",
+                },
+              ],
+              "role": "user",
+            },
+          ],
+          "model": "claude-3-haiku-20240307",
+        }
+      `);
+
+      expect(result.warnings).toStrictEqual([]);
+    });
+
     describe('context management', () => {
       it('should send context_management in request body', async () => {
         prepareJsonFixtureResponse('anthropic-text');
diff --git a/packages/anthropic/src/anthropic-messages-language-model.ts b/packages/anthropic/src/anthropic-messages-language-model.ts
@@ -353,6 +353,9 @@ export class AnthropicMessagesLanguageModel implements LanguageModelV3 {
       ...(anthropicOptions?.speed && {
         speed: anthropicOptions.speed,
       }),
+      ...(anthropicOptions?.cacheControl && {
+        cache_control: anthropicOptions.cacheControl,
+      }),
 
       // structured output:
       ...(useStructuredOutput &&

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +'@ai-sdk/anthropic': patch
 +---
++
 +Pass `cacheControl` provider option as top-level `cache_control` in Anthropic API request body to support automatic caching.