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Request 2 caches its request content (not the response) changedbuild-with-claude/prompt-caching

Recorded here 11 Nov 2026 17:37 UTC

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Lines−96removed

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Recorded edits41to this page, all time

The whole hunk

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2828 - claude-sonnet-4-5-20250929

2929 supportedPlatforms:

3030 Claude API: stable

31 Amazon Bedrock: stable

32 Amazon Bedrock (bedrock-runtime): stable

3133 Claude Platform on AWS: stable

3234 Claude Models on Google Cloud (Anthropic managed): stable

33 Amazon Bedrock: stable

34 Amazon Bedrock (InvokeModel): stable

3535 Claude Models on Google Cloud (Google managed): stable

3636 Microsoft Foundry: stable

3737---

from line 241

241241The lifetime is measured from the start of the request that writes or reads the cache entry, not from the end of its response. Time spent generating a response counts against the lifetime: if a response takes 4 minutes to stream, a follow-up request that reuses the same cached prefix must start within about 1 minute of that response completing.

242242

243243<Note>

244 If you find that 5 minutes is too short, Anthropic also offers a 1-hour cache duration [at additional cost](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#pricing).

244 If you find that 5 minutes is too short, Anthropic also offers a 1-hour cache duration at additional cost (see [Pricing](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#pricing)).

245245

246246 For more information, see [1-hour cache duration](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#1-hour-cache-duration).

247247</Note>

from line 546

546546* If the last block is not eligible as an automatic cache breakpoint target, the system silently walks backward to find the nearest eligible block. If none is found, caching is skipped.

547547

548548<Note>

549 Automatic caching is available on every platform except the legacy [Amazon Bedrock (Opus 4.6 and earlier)](https://platform.claude.com/docs/en/build-with-claude/claude-on-amazon-bedrock-legacy) integration. On that integration, the API returns a 400 error for a top-level `cache_control` field, so use [explicit cache breakpoints](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#explicit-cache-breakpoints) instead.

549 Automatic caching is available on every platform except [Amazon Bedrock (`bedrock-runtime`)](https://platform.claude.com/docs/en/build-with-claude/claude-on-amazon-bedrock-legacy). There, the API returns a 400 error for a top-level `cache_control` field, so use [explicit cache breakpoints](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#explicit-cache-breakpoints) instead.

550550</Note>

551551

552552***

from line 628

628628* 1,024 tokens for Claude Opus 4.8, Claude Sonnet 5, Claude Sonnet 4.6, Claude Sonnet 4.5 ([deprecated](https://platform.claude.com/docs/en/about-claude/model-deprecations)), Claude Opus 4.1 ([retired, except on Claude Models on Google Cloud (Google managed) and Bedrock](https://platform.claude.com/docs/en/about-claude/model-deprecations)), Claude Opus 4 ([retired, except on Claude Models on Google Cloud (Google managed)](https://platform.claude.com/docs/en/about-claude/model-deprecations)), and Claude Sonnet 4 ([retired, except on Claude Models on Google Cloud (Google managed) and Bedrock](https://platform.claude.com/docs/en/about-claude/model-deprecations))

629629* 4,096 tokens for Claude Haiku 4.5

630630

631These minimums apply on every platform where each model is available.

631These minimums apply on each of these platforms where the model is available.

632632

633633Shorter prompts cannot be cached, even if marked with `cache_control`. Any requests to cache fewer than this number of tokens are processed without caching, and no error is returned. To check whether a prompt was cached, look at the [response usage fields](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#tracking-cache-performance): if both `cache_creation_input_tokens` and `cache_read_input_tokens` are 0, the prompt was not cached (likely because it did not meet the minimum length requirement).

634634

from line 635

635635If your prompt falls just short of the minimum for your model and platform, expanding the cached content to reach the threshold is often worthwhile. Cache reads cost significantly less than uncached input tokens, so reaching the minimum can reduce costs for frequently reused prompts.

636636

637637<Note>

638 [Bedrock](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock) is an AWS-operated platform. On Bedrock, see the [Bedrock prompt caching documentation](https://docs.aws.amazon.com/bedrock/latest/userguide/prompt-caching.html) for the per-model minimums, failure behavior, and usage-field names that apply.

638 [Amazon Bedrock (`bedrock-mantle`)](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock) is an AWS-operated platform. On Amazon Bedrock, see the [Bedrock prompt caching documentation](https://docs.aws.amazon.com/bedrock/latest/userguide/prompt-caching.html) for the per-model minimums, failure behavior, and usage-field names that apply.

639639</Note>

640640

641641For concurrent requests, note that a cache entry only becomes available after the first response starts. If you need cache hits for parallel requests, wait for the first response before sending subsequent requests.

642642

643Currently, `ephemeral` is the only supported cache type, which by default has a 5-minute lifetime.

643`ephemeral` is the only supported cache type, which by default has a 5-minute lifetime.

644644

645645### What can be cached

646646

from line 674

674674

675675The following table shows which parts of the cache are invalidated by different types of changes. ✘ indicates that the cache is invalidated, whereas ✓ indicates that the cache remains valid.

676676

678| ----------------------------------------------------- | -------------- | -------------- | -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |

679| **Tool definitions** | ✘ | ✘ | ✘ | Modifying tool definitions (names, descriptions, parameters) invalidates the entire cache |

680| **Web search toggle** | ✓ | ✘ | ✘ | Enabling/disabling web search modifies the system prompt |

681| **Citations toggle** | ✓ | ✘ | ✘ | Enabling/disabling citations modifies the system prompt |

682| **Speed setting** | ✓ | ✘ | ✘ | Switching between [`speed: "fast"` and standard speed](https://platform.claude.com/docs/en/build-with-claude/fast-mode) invalidates system and message caches |

683| **Tool choice** | ✓ | ✓ | ✘ | Changes to the `tool_choice` parameter only affect message blocks |

684| **Images** | ✓ | ✓ | ✘ | Adding/removing images anywhere in the prompt affects message blocks |

685| **Thinking parameters** | Model-specific | Model-specific | ✘ | The thinking configuration (mode, and `budget_tokens` in extended mode) is rendered into the prompt, so changing it always invalidates message blocks; tool and system caches are also invalidated on models that render the configuration ahead of them. See [Thinking and prompt caching](https://platform.claude.com/docs/en/build-with-claude/thinking#thinking-and-prompt-caching). |

686| **Effort setting** | Model-specific | Model-specific | ✘ | Changing the [`output_config.effort`](https://platform.claude.com/docs/en/build-with-claude/effort) value always invalidates message blocks, with the same model-specific effect on tool and system caches as thinking parameters. Setting effort explicitly to the model’s default is equivalent to omitting it and does not invalidate. On models that support [per-message effort](https://platform.claude.com/docs/en/build-with-claude/effort#change-effort-mid-conversation-beta), an effort change carried in a `role: "system"` message inside `messages` leaves the cached prefix intact. |

687| **Non-tool results passed to requests with thinking** | ✓ | ✓ | Model-specific | On Opus 4.5+, Sonnet 4.6+, and Haiku 5.5, thinking blocks are preserved by default, so the cache remains valid (✓). On earlier Opus/Sonnet models and Haiku models through Claude Haiku 4.5, all previously-cached thinking blocks are stripped from context, and any messages that follow those thinking blocks are removed from the cache (✘). For more details, see [Caching with thinking blocks](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#caching-with-thinking-blocks). |

688| **Dropped thinking blocks** | ✓ | ✓ | ✘ | When the API drops a thinking block that isn’t [preserved](https://platform.claude.com/docs/en/build-with-claude/thinking#preserved-thinking) on that request, the cached prefix changes from that block’s position onward on that request. Blocks the receiving model can read, passed back unchanged, keep the cache intact. |

679| **Tool definitions** | ✘ | ✘ | ✘ | Modifying tool definitions (names, descriptions, parameters) invalidates the entire cache |

680| **Web search toggle** | ✓ | ✘ | ✘ | Enabling/disabling web search modifies the system prompt |

681| **Citations toggle** | ✓ | ✘ | ✘ | Enabling/disabling citations modifies the system prompt |

683| **Tool choice** | ✓ | ✓ | ✘ | Changes to the `tool_choice` parameter only affect message blocks |

684| **Images** | ✓ | ✓ | ✘ | Adding/removing images anywhere in the prompt affects message blocks |

686| **Effort setting** | Model-specific | Model-specific | ✘ | Changing the [`output_config.effort`](https://platform.claude.com/docs/en/build-with-claude/effort) value always invalidates message blocks, with the same model-specific effect on tool and system caches as thinking parameters. Setting effort explicitly to the model’s default is equivalent to omitting it and does not invalidate. On models that support [per-message effort](https://platform.claude.com/docs/en/build-with-claude/effort-per-message), an effort change carried in a `role: "system"` message inside `messages` leaves the cached prefix intact. |

689689

690690On models that support [mid-conversation tool changes](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages#mid-conversation-tool-changes), the `inline-tools-2026-09-15` beta header lets you add a tool, or change a tool’s definition, partway through a conversation without editing `tools`. Send the definition in a `tool_addition` block in a mid-conversation system message and leave `tools` exactly as you first sent it. The cached prefix still matches, so only the appended message is processed as new input. The one exception is a `tools` array with no non-deferred tool, where the first tool defined this way costs one full cache miss on that request. See [Define tools in a message](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages#define-tools-in-a-message-beta).

691691

692692<Note>

693 On Claude Fable 5.2, [Claude Mythos 5.2](https://platform.claude.com/docs/en/models/mythos-5-2/overview), Claude Fable 5.1, [Claude Mythos 5.1](https://platform.claude.com/docs/en/models/mythos-5-1/overview), Claude Fable 5, [Claude Mythos 5](https://platform.claude.com/docs/en/models/mythos-5/overview), Claude Opus 5.5, Claude Opus 4.8, Claude Opus 5, Claude Sonnet 5.5, and Claude Haiku 5.5, you can add a new system instruction partway through a conversation without invalidating the system or message caches. Append a `{"role": "system"}` message to `messages` instead of editing the top-level `system` field, so the cached prefix stays unchanged. This feature is not available on Claude Sonnet 5. Use the top-level `system` field instead. See [Mid-conversation system messages and tool changes](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages).

693 On Claude Fable 5.2, [Claude Mythos 5.2](https://platform.claude.com/docs/en/models/mythos-5-2/overview), Claude Fable 5.1, [Claude Mythos 5.1](https://platform.claude.com/docs/en/models/mythos-5-1/overview), Claude Fable 5, [Claude Mythos 5](https://platform.claude.com/docs/en/models/mythos-5/overview), Claude Opus 5.5, Claude Opus 5, Claude Opus 4.8, Claude Sonnet 5.5, and Claude Haiku 5.5, you can add a new system instruction partway through a conversation without invalidating the system or message caches. Append a `{"role": "system"}` message to `messages` instead of editing the top-level `system` field, so the cached prefix stays unchanged. This feature is not available on Claude Sonnet 5. Use the top-level `system` field instead. See [Mid-conversation system messages and tool changes](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages).

694694</Note>

695695

696696### Tracking cache performance

from line 831

831831

832832## 1-hour cache duration

833833

834If you find that 5 minutes is too short, Anthropic also offers a 1-hour cache duration [at additional cost](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#pricing).

834If you find that 5 minutes is too short, Anthropic also offers a 1-hour cache duration at additional cost (see [Pricing](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#pricing)).

835835

836836<Note>

837 The 1-hour cache duration is available on the Claude API, [Amazon Bedrock](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock), [Amazon Bedrock (Opus 4.6 and earlier)](https://platform.claude.com/docs/en/build-with-claude/claude-on-amazon-bedrock-legacy), [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws), [Claude Models on Google Cloud (Google managed)](https://platform.claude.com/docs/en/build-with-claude/claude-models-on-google-cloud/google-managed), and [Microsoft Foundry](https://platform.claude.com/docs/en/build-with-claude/claude-in-microsoft-foundry).

837 The 1-hour cache duration is available on the Claude API, [Amazon Bedrock (`bedrock-mantle`)](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock), [Amazon Bedrock (`bedrock-runtime`)](https://platform.claude.com/docs/en/build-with-claude/claude-on-amazon-bedrock-legacy), [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws), [Claude Models on Google Cloud (Google managed)](https://platform.claude.com/docs/en/build-with-claude/claude-models-on-google-cloud/google-managed), and [Microsoft Foundry](https://platform.claude.com/docs/en/build-with-claude/claude-in-microsoft-foundry).

838838</Note>

839839

840840To use the extended cache, include `ttl` in the `cache_control` definition like this:

from line 2493

24932493 system=[

24942494 {

24952495 "type": "text",

2496 "text": "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

2496 "text": """You are a helpful research assistant with access to a document knowledge base.

2497

2498 # Instructions

2499 - Always search for relevant documents before answering

2500 - Provide citations for your sources

2501 - Be objective and accurate in your responses

2502 - If multiple documents contain relevant information, synthesize them

2503 - Acknowledge when information is not available in the knowledge base""",

24972504 "cache_control": {"type": "ephemeral"},

24982505 },

24992506 {

25002507 "type": "text",

2501 "text": "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

2508 "text": """# Knowledge Base Context

2509

2510 Here are the relevant documents for this conversation:

2511

2512 ## Document 1: Solar System Overview

2513 The solar system consists of the Sun and all objects that orbit it...

2514

2515 ## Document 2: Planetary Characteristics

2516 Each planet has unique features. Mercury is the smallest planet...

2517

2518 ## Document 3: Mars Exploration

2519 Mars has been a target of exploration for decades...

2520

2521 [Additional documents...]""",

25022522 "cache_control": {"type": "ephemeral"},

25032523 },

25042524 ],

from line 2612

25922612 system: [

25932613 {

25942614 type: "text",

2595 text: "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

2615 text: `You are a helpful research assistant with access to a document knowledge base.

2616

2617 # Instructions

2618 - Always search for relevant documents before answering

2619 - Provide citations for your sources

2620 - Be objective and accurate in your responses

2621 - If multiple documents contain relevant information, synthesize them

2622 - Acknowledge when information is not available in the knowledge base`,

25962623 cache_control: { type: "ephemeral" }

25972624 },

25982625 {

25992626 type: "text",

2600 text: "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

2627 text: `# Knowledge Base Context

2628

2629 Here are the relevant documents for this conversation:

2630

2631 ## Document 1: Solar System Overview

2632 The solar system consists of the Sun and all objects that orbit it...

2633

2634 ## Document 2: Planetary Characteristics

2635 Each planet has unique features. Mercury is the smallest planet...

2636

2637 ## Document 3: Mars Exploration

2638 Mars has been a target of exploration for decades...

2639

2640 [Additional documents...]`,

26012641 cache_control: { type: "ephemeral" }

26022642 }

26032643 ],

from line 2736

26962736 {

26972737 new TextBlockParam()

26982738 {

2699 Text = "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

2739 Text = """

2740 You are a helpful research assistant with access to a document knowledge base.

2741

2742 # Instructions

2743 - Always search for relevant documents before answering

2744 - Provide citations for your sources

2745 - Be objective and accurate in your responses

2746 - If multiple documents contain relevant information, synthesize them

2747 - Acknowledge when information is not available in the knowledge base

2748 """,

27002749 CacheControl = new CacheControlEphemeral(),

27012750 },

27022751 new TextBlockParam()

27032752 {

2704 Text = "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

2753 Text = """

2754 # Knowledge Base Context

2755

2756 Here are the relevant documents for this conversation:

2757

2758 ## Document 1: Solar System Overview

2759 The solar system consists of the Sun and all objects that orbit it...

2760

2761 ## Document 2: Planetary Characteristics

2762 Each planet has unique features. Mercury is the smallest planet...

2763

2764 ## Document 3: Mars Exploration

2765 Mars has been a target of exploration for decades...

2766

2767 [Additional documents...]

2768 """,

27052769 CacheControl = new CacheControlEphemeral(),

27062770 },

27072771 }),

from line 2821

27572821 ```

27582822

27592823 ```go Go

2760 client := anthropic.NewClient()

2824 client := anthropic.NewClient()

27612825

2762 response, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{

2763 Model: anthropic.ModelClaudeOpus5_5,

2764 MaxTokens: 1024,

2765 Tools: []anthropic.ToolUnionParam{

2766 {OfTool: &anthropic.ToolParam{

2767 Name: "search_documents",

2768 Description: anthropic.String("Search through the knowledge base"),

2769 InputSchema: anthropic.ToolInputSchemaParam{

2770 Properties: map[string]any{

2771 "query": map[string]any{

2772 "type": "string",

2773 "description": "Search query",

2826 response, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{

2827 Model: anthropic.ModelClaudeOpus5_5,

2828 MaxTokens: 1024,

2829 Tools: []anthropic.ToolUnionParam{

2830 {OfTool: &anthropic.ToolParam{

2831 Name: "search_documents",

2832 Description: anthropic.String("Search through the knowledge base"),

2833 InputSchema: anthropic.ToolInputSchemaParam{

2834 Properties: map[string]any{

2835 "query": map[string]any{

2836 "type": "string",

2837 "description": "Search query",

2838 },

27742839 },

2840 Required: []string{"query"},

27752841 },

2776 Required: []string{"query"},

2777 },

2778 }},

2779 {OfTool: &anthropic.ToolParam{

2780 Name: "get_document",

2781 Description: anthropic.String("Retrieve a specific document by ID"),

2782 InputSchema: anthropic.ToolInputSchemaParam{

2783 Properties: map[string]any{

2784 "doc_id": map[string]any{

2785 "type": "string",

2786 "description": "Document ID",

2842 }},

2843 {OfTool: &anthropic.ToolParam{

2844 Name: "get_document",

2845 Description: anthropic.String("Retrieve a specific document by ID"),

2846 InputSchema: anthropic.ToolInputSchemaParam{

2847 Properties: map[string]any{

2848 "doc_id": map[string]any{

2849 "type": "string",

2850 "description": "Document ID",

2851 },

27872852 },

2853 Required: []string{"doc_id"},

27882854 },

2789 Required: []string{"doc_id"},

2855 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2856 }},

2857 },

2858 System: []anthropic.TextBlockParam{

2859 {

2860 Text: `You are a helpful research assistant with access to a document knowledge base.

2861

2862 # Instructions

2863 - Always search for relevant documents before answering

2864 - Provide citations for your sources

2865 - Be objective and accurate in your responses

2866 - If multiple documents contain relevant information, synthesize them

2867 - Acknowledge when information is not available in the knowledge base`,

2868 CacheControl: anthropic.NewCacheControlEphemeralParam(),

27902869 },

2791 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2792 }},

2793 },

2794 System: []anthropic.TextBlockParam{

2795 {

2796 Text: "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

2797 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2870 {

2871 Text: `# Knowledge Base Context

2872

2873 Here are the relevant documents for this conversation:

2874

2875 ## Document 1: Solar System Overview

2876 The solar system consists of the Sun and all objects that orbit it...

2877

2878 ## Document 2: Planetary Characteristics

2879 Each planet has unique features. Mercury is the smallest planet...

2880

2881 ## Document 3: Mars Exploration

2882 Mars has been a target of exploration for decades...

2883

2884 [Additional documents...]`,

2885 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2886 },

27982887 },

2799 {

2800 Text: "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

2801 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2888 Messages: []anthropic.MessageParam{

2889 anthropic.NewUserMessage(anthropic.NewTextBlock("Can you search for information about Mars rovers?")),

2890 anthropic.NewAssistantMessage(anthropic.NewToolUseBlock(

2891 "tool_1",

2892 map[string]any{"query": "Mars rovers"},

2893 "search_documents",

2894 )),

2895 anthropic.NewUserMessage(anthropic.NewToolResultBlock(

2896 "tool_1",

2897 "Found 3 relevant documents: Document 3 (Mars Exploration), Document 7 (Rover Technology), Document 9 (Mission History)",

2898 false,

2899 )),

2900 anthropic.NewAssistantMessage(anthropic.NewTextBlock("I found 3 relevant documents about Mars rovers. Let me get more details from the Mars Exploration document.")),

2901 anthropic.NewUserMessage(anthropic.ContentBlockParamUnion{OfText: &anthropic.TextBlockParam{

2902 Text: "Yes, please tell me about the Perseverance rover specifically.",

2903 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2904 }}),

28022905 },

2803 },

2804 Messages: []anthropic.MessageParam{

2805 anthropic.NewUserMessage(anthropic.NewTextBlock("Can you search for information about Mars rovers?")),

2806 anthropic.NewAssistantMessage(anthropic.NewToolUseBlock(

2807 "tool_1",

2808 map[string]any{"query": "Mars rovers"},

2809 "search_documents",

2810 )),

2811 anthropic.NewUserMessage(anthropic.NewToolResultBlock(

2812 "tool_1",

2813 "Found 3 relevant documents: Document 3 (Mars Exploration), Document 7 (Rover Technology), Document 9 (Mission History)",

2814 false,

2815 )),

2816 anthropic.NewAssistantMessage(anthropic.NewTextBlock("I found 3 relevant documents about Mars rovers. Let me get more details from the Mars Exploration document.")),

2817 anthropic.NewUserMessage(anthropic.ContentBlockParamUnion{OfText: &anthropic.TextBlockParam{

2818 Text: "Yes, please tell me about the Perseverance rover specifically.",

2819 CacheControl: anthropic.NewCacheControlEphemeralParam(),

2820 }}),

2821 },

2822 })

2823 if err != nil {

2824 log.Fatal(err)

2825 }

2826 fmt.Println(response.Usage.RawJSON())

2906 })

2907 if err != nil {

2908 log.Fatal(err)

2909 }

2910 fmt.Println(response.Usage.RawJSON())

28272911 ```

28282912

28292913 ```java Java

from line 2960

28762960 List.of(

28772961 TextBlockParam.builder()

28782962 .text(

2879 "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base"

2963 """

2964 You are a helpful research assistant with access to a document knowledge base.

2965

2966 # Instructions

2967 - Always search for relevant documents before answering

2968 - Provide citations for your sources

2969 - Be objective and accurate in your responses

2970 - If multiple documents contain relevant information, synthesize them

2971 - Acknowledge when information is not available in the knowledge base"""

28802972 )

28812973 .cacheControl(CacheControlEphemeral.builder().build())

28822974 .build(),

28832975 TextBlockParam.builder()

28842976 .text(

2885 "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]"

2977 """

2978 # Knowledge Base Context

2979

2980 Here are the relevant documents for this conversation:

2981

2982 ## Document 1: Solar System Overview

2983 The solar system consists of the Sun and all objects that orbit it...

2984

2985 ## Document 2: Planetary Characteristics

2986 Each planet has unique features. Mercury is the smallest planet...

2987

2988 ## Document 3: Mars Exploration

2989 Mars has been a target of exploration for decades...

2990

2991 [Additional documents...]"""

28862992 )

28872993 .cacheControl(CacheControlEphemeral.builder().build())

28882994 .build()

from line 3102

29963102 system: [

29973103 [

29983104 'type' => 'text',

2999 'text' => "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

3105 'text' => <<<'TEXT'

3106 You are a helpful research assistant with access to a document knowledge base.

3107

3108 # Instructions

3109 - Always search for relevant documents before answering

3110 - Provide citations for your sources

3111 - Be objective and accurate in your responses

3112 - If multiple documents contain relevant information, synthesize them

3113 - Acknowledge when information is not available in the knowledge base

3114 TEXT,

30003115 'cache_control' => ['type' => 'ephemeral']

30013116 ],

30023117 [

30033118 'type' => 'text',

3004 'text' => "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

3119 'text' => <<<'TEXT'

3120 # Knowledge Base Context

3121

3122 Here are the relevant documents for this conversation:

3123

3124 ## Document 1: Solar System Overview

3125 The solar system consists of the Sun and all objects that orbit it...

3126

3127 ## Document 2: Planetary Characteristics

3128 Each planet has unique features. Mercury is the smallest planet...

3129

3130 ## Document 3: Mars Exploration

3131 Mars has been a target of exploration for decades...

3132

3133 [Additional documents...]

3134 TEXT,

30053135 'cache_control' => ['type' => 'ephemeral']

30063136 ]

30073137 ],

from line 3211

30813211 system_: [

30823212 {

30833213 type: "text",

3084 text: "You are a helpful research assistant with access to a document knowledge base.\n\n# Instructions\n- Always search for relevant documents before answering\n- Provide citations for your sources\n- Be objective and accurate in your responses\n- If multiple documents contain relevant information, synthesize them\n- Acknowledge when information is not available in the knowledge base",

3214 text: <<~TEXT.chomp,

3215 You are a helpful research assistant with access to a document knowledge base.

3216

3217 # Instructions

3218 - Always search for relevant documents before answering

3219 - Provide citations for your sources

3220 - Be objective and accurate in your responses

3221 - If multiple documents contain relevant information, synthesize them

3222 - Acknowledge when information is not available in the knowledge base

3223 TEXT

30853224 cache_control: { type: "ephemeral" }

30863225 },

30873226 {

30883227 type: "text",

3089 text: "# Knowledge Base Context\n\nHere are the relevant documents for this conversation:\n\n## Document 1: Solar System Overview\nThe solar system consists of the Sun and all objects that orbit it...\n\n## Document 2: Planetary Characteristics\nEach planet has unique features. Mercury is the smallest planet...\n\n## Document 3: Mars Exploration\nMars has been a target of exploration for decades...\n\n[Additional documents...]",

3228 text: <<~TEXT.chomp,

3229 # Knowledge Base Context

3230

3231 Here are the relevant documents for this conversation:

3232

3233 ## Document 1: Solar System Overview

3234 The solar system consists of the Sun and all objects that orbit it...

3235

3236 ## Document 2: Planetary Characteristics

3237 Each planet has unique features. Mercury is the smallest planet...

3238

3239 ## Document 3: Mars Exploration

3240 Mars has been a target of exploration for decades...

3241

3242 [Additional documents...]

3243 TEXT

30903244 cache_control: { type: "ephemeral" }

30913245 }

30923246 ],

from line 3432

32783432 </Accordion>

32793433

32803434 <Accordion title="Can I manually clear the cache?">

3281 Currently, there’s no way to manually clear the cache. Cached prefixes automatically expire after a minimum of 5 minutes of inactivity.

3435 There’s no way to manually clear the cache. Cached prefixes automatically expire after a minimum of 5 minutes of inactivity.

32823436 </Accordion>

32833437

32843438 <Accordion title="How can I track the effectiveness of my caching strategy?">

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