# Models ## List Models `ModelListPageResponse Models.List(ModelListParams?parameters, CancellationTokencancellationToken = default)` **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 parameters` - `string afterID` Query param: ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately after this object. - `string beforeID` Query param: ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately before this object. - `Long limit` Query param: Number of items to return per page. Defaults to `20`. Ranges from `1` to `1000`. - `IReadOnlyList betas` Header param: Optional header to specify the beta version(s) you want to use. - `"message-batches-2024-09-24"MessageBatches2024_09_24` - `"prompt-caching-2024-07-31"PromptCaching2024_07_31` - `"computer-use-2024-10-22"ComputerUse2024_10_22` - `"computer-use-2025-01-24"ComputerUse2025_01_24` - `"pdfs-2024-09-25"Pdfs2024_09_25` - `"token-counting-2024-11-01"TokenCounting2024_11_01` - `"token-efficient-tools-2025-02-19"TokenEfficientTools2025_02_19` - `"output-128k-2025-02-19"Output128k2025_02_19` - `"files-api-2025-04-14"FilesApi2025_04_14` - `"mcp-client-2025-04-04"McpClient2025_04_04` - `"mcp-client-2025-11-20"McpClient2025_11_20` - `"dev-full-thinking-2025-05-14"DevFullThinking2025_05_14` - `"interleaved-thinking-2025-05-14"InterleavedThinking2025_05_14` - `"code-execution-2025-05-22"CodeExecution2025_05_22` - `"extended-cache-ttl-2025-04-11"ExtendedCacheTtl2025_04_11` - `"context-1m-2025-08-07"Context1m2025_08_07` - `"context-management-2025-06-27"ContextManagement2025_06_27` - `"model-context-window-exceeded-2025-08-26"ModelContextWindowExceeded2025_08_26` - `"skills-2025-10-02"Skills2025_10_02` - `"fast-mode-2026-02-01"FastMode2026_02_01` - `"output-300k-2026-03-24"Output300k2026_03_24` - `"user-profiles-2026-03-24"UserProfiles2026_03_24` - `"advisor-tool-2026-03-01"AdvisorTool2026_03_01` - `"managed-agents-2026-04-01"ManagedAgents2026_04_01` - `"cache-diagnosis-2026-04-07"CacheDiagnosis2026_04_07` - `"thinking-token-count-2026-05-13"ThinkingTokenCount2026_05_13` - `"server-side-fallback-2026-06-01"ServerSideFallback2026_06_01` - `"fallback-credit-2026-06-01"FallbackCredit2026_06_01` ### Returns - `class ModelListPageResponse:` - `required IReadOnlyList Data` - `required string ID` Unique model identifier. - `required ModelCapabilities? Capabilities` Model capability information. - `required CapabilitySupport Batch` Whether the model supports the Batch API. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Citations` Whether the model supports citation generation. - `required CapabilitySupport CodeExecution` Whether the model supports code execution tools. - `required ContextManagementCapability ContextManagement` Context management support and available strategies. - `required CapabilitySupport? ClearThinking20251015` Indicates whether a capability is supported. - `required CapabilitySupport? ClearToolUses20250919` Indicates whether a capability is supported. - `required CapabilitySupport? Compact20260112` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. - `required EffortCapability Effort` Effort (reasoning_effort) support and available levels. - `required CapabilitySupport High` Whether the model supports high effort level. - `required CapabilitySupport Low` Whether the model supports low effort level. - `required CapabilitySupport Max` Whether the model supports max effort level. - `required CapabilitySupport Medium` Whether the model supports medium effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? Xhigh` Indicates whether a capability is supported. - `required CapabilitySupport ImageInput` Whether the model accepts image content blocks. - `required CapabilitySupport PdfInput` Whether the model accepts PDF content blocks. - `required CapabilitySupport StructuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `required ThinkingCapability Thinking` Thinking capability and supported type configurations. - `required Boolean Supported` Whether this capability is supported by the model. - `required ThinkingTypes Types` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'. - `required DateTimeOffset 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. - `required string DisplayName` A human-readable name for the model. - `required Long? MaxInputTokens` Maximum input context window size in tokens for this model. - `required Long? MaxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonElement Type "model"constant` Object type. For Models, this is always `"model"`. - `required string? FirstID` First ID in the `data` list. Can be used as the `before_id` for the previous page. - `required Boolean HasMore` Indicates if there are more results in the requested page direction. - `required string? LastID` Last ID in the `data` list. Can be used as the `after_id` for the next page. ### Example ```csharp ModelListParams parameters = new(); var page = await client.Models.List(parameters); await foreach (var item in page.Paginate()) { Console.WriteLine(item); } ``` #### Response ```json { "data": [ { "id": "claude-opus-4-6", "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 `ModelInfo Models.Retrieve(ModelRetrieveParamsparameters, CancellationTokencancellationToken = default)` **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 parameters` - `required string modelID` Model identifier or alias. - `IReadOnlyList betas` Optional header to specify the beta version(s) you want to use. - `"message-batches-2024-09-24"MessageBatches2024_09_24` - `"prompt-caching-2024-07-31"PromptCaching2024_07_31` - `"computer-use-2024-10-22"ComputerUse2024_10_22` - `"computer-use-2025-01-24"ComputerUse2025_01_24` - `"pdfs-2024-09-25"Pdfs2024_09_25` - `"token-counting-2024-11-01"TokenCounting2024_11_01` - `"token-efficient-tools-2025-02-19"TokenEfficientTools2025_02_19` - `"output-128k-2025-02-19"Output128k2025_02_19` - `"files-api-2025-04-14"FilesApi2025_04_14` - `"mcp-client-2025-04-04"McpClient2025_04_04` - `"mcp-client-2025-11-20"McpClient2025_11_20` - `"dev-full-thinking-2025-05-14"DevFullThinking2025_05_14` - `"interleaved-thinking-2025-05-14"InterleavedThinking2025_05_14` - `"code-execution-2025-05-22"CodeExecution2025_05_22` - `"extended-cache-ttl-2025-04-11"ExtendedCacheTtl2025_04_11` - `"context-1m-2025-08-07"Context1m2025_08_07` - `"context-management-2025-06-27"ContextManagement2025_06_27` - `"model-context-window-exceeded-2025-08-26"ModelContextWindowExceeded2025_08_26` - `"skills-2025-10-02"Skills2025_10_02` - `"fast-mode-2026-02-01"FastMode2026_02_01` - `"output-300k-2026-03-24"Output300k2026_03_24` - `"user-profiles-2026-03-24"UserProfiles2026_03_24` - `"advisor-tool-2026-03-01"AdvisorTool2026_03_01` - `"managed-agents-2026-04-01"ManagedAgents2026_04_01` - `"cache-diagnosis-2026-04-07"CacheDiagnosis2026_04_07` - `"thinking-token-count-2026-05-13"ThinkingTokenCount2026_05_13` - `"server-side-fallback-2026-06-01"ServerSideFallback2026_06_01` - `"fallback-credit-2026-06-01"FallbackCredit2026_06_01` ### Returns - `class ModelInfo:` - `required string ID` Unique model identifier. - `required ModelCapabilities? Capabilities` Model capability information. - `required CapabilitySupport Batch` Whether the model supports the Batch API. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Citations` Whether the model supports citation generation. - `required CapabilitySupport CodeExecution` Whether the model supports code execution tools. - `required ContextManagementCapability ContextManagement` Context management support and available strategies. - `required CapabilitySupport? ClearThinking20251015` Indicates whether a capability is supported. - `required CapabilitySupport? ClearToolUses20250919` Indicates whether a capability is supported. - `required CapabilitySupport? Compact20260112` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. - `required EffortCapability Effort` Effort (reasoning_effort) support and available levels. - `required CapabilitySupport High` Whether the model supports high effort level. - `required CapabilitySupport Low` Whether the model supports low effort level. - `required CapabilitySupport Max` Whether the model supports max effort level. - `required CapabilitySupport Medium` Whether the model supports medium effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? Xhigh` Indicates whether a capability is supported. - `required CapabilitySupport ImageInput` Whether the model accepts image content blocks. - `required CapabilitySupport PdfInput` Whether the model accepts PDF content blocks. - `required CapabilitySupport StructuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `required ThinkingCapability Thinking` Thinking capability and supported type configurations. - `required Boolean Supported` Whether this capability is supported by the model. - `required ThinkingTypes Types` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'. - `required DateTimeOffset 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. - `required string DisplayName` A human-readable name for the model. - `required Long? MaxInputTokens` Maximum input context window size in tokens for this model. - `required Long? MaxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonElement Type "model"constant` Object type. For Models, this is always `"model"`. ### Example ```csharp ModelRetrieveParams parameters = new() { ModelID = "model_id" }; var modelInfo = await client.Models.Retrieve(parameters); Console.WriteLine(modelInfo); ``` #### Response ```json { "id": "claude-opus-4-6", "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 ### Capability Support - `class CapabilitySupport:` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. ### Context Management Capability - `class ContextManagementCapability:` Context management capability details. - `required CapabilitySupport? ClearThinking20251015` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? ClearToolUses20250919` Indicates whether a capability is supported. - `required CapabilitySupport? Compact20260112` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. ### Effort Capability - `class EffortCapability:` Effort (reasoning_effort) capability details. - `required CapabilitySupport High` Whether the model supports high effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Low` Whether the model supports low effort level. - `required CapabilitySupport Max` Whether the model supports max effort level. - `required CapabilitySupport Medium` Whether the model supports medium effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? Xhigh` Indicates whether a capability is supported. ### Model Capabilities - `class ModelCapabilities:` Model capability information. - `required CapabilitySupport Batch` Whether the model supports the Batch API. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Citations` Whether the model supports citation generation. - `required CapabilitySupport CodeExecution` Whether the model supports code execution tools. - `required ContextManagementCapability ContextManagement` Context management support and available strategies. - `required CapabilitySupport? ClearThinking20251015` Indicates whether a capability is supported. - `required CapabilitySupport? ClearToolUses20250919` Indicates whether a capability is supported. - `required CapabilitySupport? Compact20260112` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. - `required EffortCapability Effort` Effort (reasoning_effort) support and available levels. - `required CapabilitySupport High` Whether the model supports high effort level. - `required CapabilitySupport Low` Whether the model supports low effort level. - `required CapabilitySupport Max` Whether the model supports max effort level. - `required CapabilitySupport Medium` Whether the model supports medium effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? Xhigh` Indicates whether a capability is supported. - `required CapabilitySupport ImageInput` Whether the model accepts image content blocks. - `required CapabilitySupport PdfInput` Whether the model accepts PDF content blocks. - `required CapabilitySupport StructuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `required ThinkingCapability Thinking` Thinking capability and supported type configurations. - `required Boolean Supported` Whether this capability is supported by the model. - `required ThinkingTypes Types` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'. ### Model Info - `class ModelInfo:` - `required string ID` Unique model identifier. - `required ModelCapabilities? Capabilities` Model capability information. - `required CapabilitySupport Batch` Whether the model supports the Batch API. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Citations` Whether the model supports citation generation. - `required CapabilitySupport CodeExecution` Whether the model supports code execution tools. - `required ContextManagementCapability ContextManagement` Context management support and available strategies. - `required CapabilitySupport? ClearThinking20251015` Indicates whether a capability is supported. - `required CapabilitySupport? ClearToolUses20250919` Indicates whether a capability is supported. - `required CapabilitySupport? Compact20260112` Indicates whether a capability is supported. - `required Boolean Supported` Whether this capability is supported by the model. - `required EffortCapability Effort` Effort (reasoning_effort) support and available levels. - `required CapabilitySupport High` Whether the model supports high effort level. - `required CapabilitySupport Low` Whether the model supports low effort level. - `required CapabilitySupport Max` Whether the model supports max effort level. - `required CapabilitySupport Medium` Whether the model supports medium effort level. - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport? Xhigh` Indicates whether a capability is supported. - `required CapabilitySupport ImageInput` Whether the model accepts image content blocks. - `required CapabilitySupport PdfInput` Whether the model accepts PDF content blocks. - `required CapabilitySupport StructuredOutputs` Whether the model supports structured output / JSON mode / strict tool schemas. - `required ThinkingCapability Thinking` Thinking capability and supported type configurations. - `required Boolean Supported` Whether this capability is supported by the model. - `required ThinkingTypes Types` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'. - `required DateTimeOffset 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. - `required string DisplayName` A human-readable name for the model. - `required Long? MaxInputTokens` Maximum input context window size in tokens for this model. - `required Long? MaxTokens` Maximum value for the `max_tokens` parameter when using this model. - `JsonElement Type "model"constant` Object type. For Models, this is always `"model"`. ### Thinking Capability - `class ThinkingCapability:` Thinking capability details. - `required Boolean Supported` Whether this capability is supported by the model. - `required ThinkingTypes Types` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'. ### Thinking Types - `class ThinkingTypes:` Supported thinking type configurations. - `required CapabilitySupport Adaptive` Whether the model supports thinking with type 'adaptive' (auto). - `required Boolean Supported` Whether this capability is supported by the model. - `required CapabilitySupport Enabled` Whether the model supports thinking with type 'enabled'.