# Models ## List Models `ModelListPage beta().models().list(ModelListParamsparams = ModelListParams.none(), RequestOptionsrequestOptions = RequestOptions.none())` **get** `/v1/models` List available models. The Models API response can be used to determine which models are available for use in the API. More recently released models are listed first. ### Parameters - `ModelListParams params` - `Optional afterId` ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately after this object. - `Optional beforeId` ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately before this object. - `Optional limit` Number of items to return per page. Defaults to `20`. Ranges from `1` to `1000`. - `Optional> betas` Optional header to specify the beta version(s) you want to use. - `MESSAGE_BATCHES_2024_09_24("message-batches-2024-09-24")` - `PROMPT_CACHING_2024_07_31("prompt-caching-2024-07-31")` - `COMPUTER_USE_2024_10_22("computer-use-2024-10-22")` - `COMPUTER_USE_2025_01_24("computer-use-2025-01-24")` - `PDFS_2024_09_25("pdfs-2024-09-25")` - `TOKEN_COUNTING_2024_11_01("token-counting-2024-11-01")` - `TOKEN_EFFICIENT_TOOLS_2025_02_19("token-efficient-tools-2025-02-19")` - `OUTPUT_128K_2025_02_19("output-128k-2025-02-19")` - `FILES_API_2025_04_14("files-api-2025-04-14")` - `MCP_CLIENT_2025_04_04("mcp-client-2025-04-04")` - `MCP_CLIENT_2025_11_20("mcp-client-2025-11-20")` - `DEV_FULL_THINKING_2025_05_14("dev-full-thinking-2025-05-14")` - `INTERLEAVED_THINKING_2025_05_14("interleaved-thinking-2025-05-14")` - `CODE_EXECUTION_2025_05_22("code-execution-2025-05-22")` - `EXTENDED_CACHE_TTL_2025_04_11("extended-cache-ttl-2025-04-11")` - `CONTEXT_1M_2025_08_07("context-1m-2025-08-07")` - `CONTEXT_MANAGEMENT_2025_06_27("context-management-2025-06-27")` - `MODEL_CONTEXT_WINDOW_EXCEEDED_2025_08_26("model-context-window-exceeded-2025-08-26")` - `SKILLS_2025_10_02("skills-2025-10-02")` - `FAST_MODE_2026_02_01("fast-mode-2026-02-01")` - `OUTPUT_300K_2026_03_24("output-300k-2026-03-24")` - `USER_PROFILES_2026_03_24("user-profiles-2026-03-24")` - `ADVISOR_TOOL_2026_03_01("advisor-tool-2026-03-01")` - `MANAGED_AGENTS_2026_04_01("managed-agents-2026-04-01")` - `CACHE_DIAGNOSIS_2026_04_07("cache-diagnosis-2026-04-07")` - `THINKING_TOKEN_COUNT_2026_05_13("thinking-token-count-2026-05-13")` - `SERVER_SIDE_FALLBACK_2026_06_01("server-side-fallback-2026-06-01")` - `FALLBACK_CREDIT_2026_06_01("fallback-credit-2026-06-01")` ### Returns - `class BetaModelInfo:` - `String id` Unique model identifier. - `Optional> allowedFallbackModels` Model IDs this model accepts as `fallbacks[i].model` on the Messages API. An empty list means the `fallbacks` parameter is not supported for this model as primary. - `Optional capabilities` Model capability information. - `BetaCapabilitySupport batch` Whether the model supports the Batch API. - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport citations` Whether the model supports citation generation. - `BetaCapabilitySupport codeExecution` Whether the model supports code execution tools. - `BetaContextManagementCapability contextManagement` Context management support and available strategies. - `Optional clearThinking20251015` Indicates whether a capability is supported. - `Optional clearToolUses20250919` Indicates whether a capability is supported. - `Optional compact20260112` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. - `BetaEffortCapability effort` Effort (reasoning_effort) support and available levels. - `BetaCapabilitySupport high` Whether the model supports high effort level. - `BetaCapabilitySupport low` Whether the model supports low effort level. - `BetaCapabilitySupport max` Whether the model supports max effort level. - `BetaCapabilitySupport medium` Whether the model supports medium effort level. - `boolean supported` Whether this capability is supported by the model. - `Optional xhigh` Indicates whether a capability is supported. - `BetaCapabilitySupport imageInput` Whether the model accepts image content blocks. - `BetaCapabilitySupport pdfInput` Whether the model accepts PDF content blocks. - `BetaCapabilitySupport structuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `BetaThinkingCapability thinking` Thinking capability and supported type configurations. - `boolean supported` Whether this capability is supported by the model. - `BetaThinkingTypes types` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'. - `LocalDateTime createdAt` RFC 3339 datetime string representing the time at which the model was released. May be set to an epoch value if the release date is unknown. - `String displayName` A human-readable name for the model. - `Optional maxInputTokens` Maximum input context window size in tokens for this model. - `Optional maxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonValue; type "model"constant` Object type. For Models, this is always `"model"`. - `MODEL("model")` ### Example ```java package com.anthropic.example; import com.anthropic.client.AnthropicClient; import com.anthropic.client.okhttp.AnthropicOkHttpClient; import com.anthropic.models.beta.models.ModelListPage; import com.anthropic.models.beta.models.ModelListParams; public final class Main { private Main() {} public static void main(String[] args) { AnthropicClient client = AnthropicOkHttpClient.fromEnv(); ModelListPage page = client.beta().models().list(); } } ``` #### Response ```json { "data": [ { "id": "claude-opus-4-6", "allowed_fallback_models": [ "string" ], "capabilities": { "batch": { "supported": true }, "citations": { "supported": true }, "code_execution": { "supported": true }, "context_management": { "clear_thinking_20251015": { "supported": true }, "clear_tool_uses_20250919": { "supported": true }, "compact_20260112": { "supported": true }, "supported": true }, "effort": { "high": { "supported": true }, "low": { "supported": true }, "max": { "supported": true }, "medium": { "supported": true }, "supported": true, "xhigh": { "supported": true } }, "image_input": { "supported": true }, "pdf_input": { "supported": true }, "structured_outputs": { "supported": true }, "thinking": { "supported": true, "types": { "adaptive": { "supported": true }, "enabled": { "supported": true } } } }, "created_at": "2026-02-04T00:00:00Z", "display_name": "Claude Opus 4.6", "max_input_tokens": 0, "max_tokens": 0, "type": "model" } ], "first_id": "first_id", "has_more": true, "last_id": "last_id" } ``` ## Get a Model `BetaModelInfo beta().models().retrieve(ModelRetrieveParamsparams = ModelRetrieveParams.none(), RequestOptionsrequestOptions = RequestOptions.none())` **get** `/v1/models/{model_id}` Get a specific model. The Models API response can be used to determine information about a specific model or resolve a model alias to a model ID. ### Parameters - `ModelRetrieveParams params` - `Optional modelId` Model identifier or alias. - `Optional> betas` Optional header to specify the beta version(s) you want to use. - `MESSAGE_BATCHES_2024_09_24("message-batches-2024-09-24")` - `PROMPT_CACHING_2024_07_31("prompt-caching-2024-07-31")` - `COMPUTER_USE_2024_10_22("computer-use-2024-10-22")` - `COMPUTER_USE_2025_01_24("computer-use-2025-01-24")` - `PDFS_2024_09_25("pdfs-2024-09-25")` - `TOKEN_COUNTING_2024_11_01("token-counting-2024-11-01")` - `TOKEN_EFFICIENT_TOOLS_2025_02_19("token-efficient-tools-2025-02-19")` - `OUTPUT_128K_2025_02_19("output-128k-2025-02-19")` - `FILES_API_2025_04_14("files-api-2025-04-14")` - `MCP_CLIENT_2025_04_04("mcp-client-2025-04-04")` - `MCP_CLIENT_2025_11_20("mcp-client-2025-11-20")` - `DEV_FULL_THINKING_2025_05_14("dev-full-thinking-2025-05-14")` - `INTERLEAVED_THINKING_2025_05_14("interleaved-thinking-2025-05-14")` - `CODE_EXECUTION_2025_05_22("code-execution-2025-05-22")` - `EXTENDED_CACHE_TTL_2025_04_11("extended-cache-ttl-2025-04-11")` - `CONTEXT_1M_2025_08_07("context-1m-2025-08-07")` - `CONTEXT_MANAGEMENT_2025_06_27("context-management-2025-06-27")` - `MODEL_CONTEXT_WINDOW_EXCEEDED_2025_08_26("model-context-window-exceeded-2025-08-26")` - `SKILLS_2025_10_02("skills-2025-10-02")` - `FAST_MODE_2026_02_01("fast-mode-2026-02-01")` - `OUTPUT_300K_2026_03_24("output-300k-2026-03-24")` - `USER_PROFILES_2026_03_24("user-profiles-2026-03-24")` - `ADVISOR_TOOL_2026_03_01("advisor-tool-2026-03-01")` - `MANAGED_AGENTS_2026_04_01("managed-agents-2026-04-01")` - `CACHE_DIAGNOSIS_2026_04_07("cache-diagnosis-2026-04-07")` - `THINKING_TOKEN_COUNT_2026_05_13("thinking-token-count-2026-05-13")` - `SERVER_SIDE_FALLBACK_2026_06_01("server-side-fallback-2026-06-01")` - `FALLBACK_CREDIT_2026_06_01("fallback-credit-2026-06-01")` ### Returns - `class BetaModelInfo:` - `String id` Unique model identifier. - `Optional> allowedFallbackModels` Model IDs this model accepts as `fallbacks[i].model` on the Messages API. An empty list means the `fallbacks` parameter is not supported for this model as primary. - `Optional capabilities` Model capability information. - `BetaCapabilitySupport batch` Whether the model supports the Batch API. - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport citations` Whether the model supports citation generation. - `BetaCapabilitySupport codeExecution` Whether the model supports code execution tools. - `BetaContextManagementCapability contextManagement` Context management support and available strategies. - `Optional clearThinking20251015` Indicates whether a capability is supported. - `Optional clearToolUses20250919` Indicates whether a capability is supported. - `Optional compact20260112` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. - `BetaEffortCapability effort` Effort (reasoning_effort) support and available levels. - `BetaCapabilitySupport high` Whether the model supports high effort level. - `BetaCapabilitySupport low` Whether the model supports low effort level. - `BetaCapabilitySupport max` Whether the model supports max effort level. - `BetaCapabilitySupport medium` Whether the model supports medium effort level. - `boolean supported` Whether this capability is supported by the model. - `Optional xhigh` Indicates whether a capability is supported. - `BetaCapabilitySupport imageInput` Whether the model accepts image content blocks. - `BetaCapabilitySupport pdfInput` Whether the model accepts PDF content blocks. - `BetaCapabilitySupport structuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `BetaThinkingCapability thinking` Thinking capability and supported type configurations. - `boolean supported` Whether this capability is supported by the model. - `BetaThinkingTypes types` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'. - `LocalDateTime createdAt` RFC 3339 datetime string representing the time at which the model was released. May be set to an epoch value if the release date is unknown. - `String displayName` A human-readable name for the model. - `Optional maxInputTokens` Maximum input context window size in tokens for this model. - `Optional maxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonValue; type "model"constant` Object type. For Models, this is always `"model"`. - `MODEL("model")` ### Example ```java package com.anthropic.example; import com.anthropic.client.AnthropicClient; import com.anthropic.client.okhttp.AnthropicOkHttpClient; import com.anthropic.models.beta.models.BetaModelInfo; import com.anthropic.models.beta.models.ModelRetrieveParams; public final class Main { private Main() {} public static void main(String[] args) { AnthropicClient client = AnthropicOkHttpClient.fromEnv(); BetaModelInfo betaModelInfo = client.beta().models().retrieve("model_id"); } } ``` #### Response ```json { "id": "claude-opus-4-6", "allowed_fallback_models": [ "string" ], "capabilities": { "batch": { "supported": true }, "citations": { "supported": true }, "code_execution": { "supported": true }, "context_management": { "clear_thinking_20251015": { "supported": true }, "clear_tool_uses_20250919": { "supported": true }, "compact_20260112": { "supported": true }, "supported": true }, "effort": { "high": { "supported": true }, "low": { "supported": true }, "max": { "supported": true }, "medium": { "supported": true }, "supported": true, "xhigh": { "supported": true } }, "image_input": { "supported": true }, "pdf_input": { "supported": true }, "structured_outputs": { "supported": true }, "thinking": { "supported": true, "types": { "adaptive": { "supported": true }, "enabled": { "supported": true } } } }, "created_at": "2026-02-04T00:00:00Z", "display_name": "Claude Opus 4.6", "max_input_tokens": 0, "max_tokens": 0, "type": "model" } ``` ## Domain Types ### Beta Capability Support - `class BetaCapabilitySupport:` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. ### Beta Context Management Capability - `class BetaContextManagementCapability:` Context management capability details. - `Optional clearThinking20251015` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. - `Optional clearToolUses20250919` Indicates whether a capability is supported. - `Optional compact20260112` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. ### Beta Effort Capability - `class BetaEffortCapability:` Effort (reasoning_effort) capability details. - `BetaCapabilitySupport high` Whether the model supports high effort level. - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport low` Whether the model supports low effort level. - `BetaCapabilitySupport max` Whether the model supports max effort level. - `BetaCapabilitySupport medium` Whether the model supports medium effort level. - `boolean supported` Whether this capability is supported by the model. - `Optional xhigh` Indicates whether a capability is supported. ### Beta Model Capabilities - `class BetaModelCapabilities:` Model capability information. - `BetaCapabilitySupport batch` Whether the model supports the Batch API. - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport citations` Whether the model supports citation generation. - `BetaCapabilitySupport codeExecution` Whether the model supports code execution tools. - `BetaContextManagementCapability contextManagement` Context management support and available strategies. - `Optional clearThinking20251015` Indicates whether a capability is supported. - `Optional clearToolUses20250919` Indicates whether a capability is supported. - `Optional compact20260112` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. - `BetaEffortCapability effort` Effort (reasoning_effort) support and available levels. - `BetaCapabilitySupport high` Whether the model supports high effort level. - `BetaCapabilitySupport low` Whether the model supports low effort level. - `BetaCapabilitySupport max` Whether the model supports max effort level. - `BetaCapabilitySupport medium` Whether the model supports medium effort level. - `boolean supported` Whether this capability is supported by the model. - `Optional xhigh` Indicates whether a capability is supported. - `BetaCapabilitySupport imageInput` Whether the model accepts image content blocks. - `BetaCapabilitySupport pdfInput` Whether the model accepts PDF content blocks. - `BetaCapabilitySupport structuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `BetaThinkingCapability thinking` Thinking capability and supported type configurations. - `boolean supported` Whether this capability is supported by the model. - `BetaThinkingTypes types` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'. ### Beta Model Info - `class BetaModelInfo:` - `String id` Unique model identifier. - `Optional> allowedFallbackModels` Model IDs this model accepts as `fallbacks[i].model` on the Messages API. An empty list means the `fallbacks` parameter is not supported for this model as primary. - `Optional capabilities` Model capability information. - `BetaCapabilitySupport batch` Whether the model supports the Batch API. - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport citations` Whether the model supports citation generation. - `BetaCapabilitySupport codeExecution` Whether the model supports code execution tools. - `BetaContextManagementCapability contextManagement` Context management support and available strategies. - `Optional clearThinking20251015` Indicates whether a capability is supported. - `Optional clearToolUses20250919` Indicates whether a capability is supported. - `Optional compact20260112` Indicates whether a capability is supported. - `boolean supported` Whether this capability is supported by the model. - `BetaEffortCapability effort` Effort (reasoning_effort) support and available levels. - `BetaCapabilitySupport high` Whether the model supports high effort level. - `BetaCapabilitySupport low` Whether the model supports low effort level. - `BetaCapabilitySupport max` Whether the model supports max effort level. - `BetaCapabilitySupport medium` Whether the model supports medium effort level. - `boolean supported` Whether this capability is supported by the model. - `Optional xhigh` Indicates whether a capability is supported. - `BetaCapabilitySupport imageInput` Whether the model accepts image content blocks. - `BetaCapabilitySupport pdfInput` Whether the model accepts PDF content blocks. - `BetaCapabilitySupport structuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `BetaThinkingCapability thinking` Thinking capability and supported type configurations. - `boolean supported` Whether this capability is supported by the model. - `BetaThinkingTypes types` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'. - `LocalDateTime createdAt` RFC 3339 datetime string representing the time at which the model was released. May be set to an epoch value if the release date is unknown. - `String displayName` A human-readable name for the model. - `Optional maxInputTokens` Maximum input context window size in tokens for this model. - `Optional maxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonValue; type "model"constant` Object type. For Models, this is always `"model"`. - `MODEL("model")` ### Beta Thinking Capability - `class BetaThinkingCapability:` Thinking capability details. - `boolean supported` Whether this capability is supported by the model. - `BetaThinkingTypes types` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'. ### Beta Thinking Types - `class BetaThinkingTypes:` Supported thinking type configurations. - `BetaCapabilitySupport adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `boolean supported` Whether this capability is supported by the model. - `BetaCapabilitySupport enabled` Whether the model supports thinking with type 'enabled'.