# Models ## List Models `client.models.list(ModelListParamsparams?, RequestOptionsoptions?): Page` **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 - `params: ModelListParams` - `after_id?: string` Query param: ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately after this object. - `before_id?: string` Query param: ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately before this object. - `limit?: number` Query param: Number of items to return per page. Defaults to `20`. Ranges from `1` to `1000`. - `betas?: Array` Header param: Optional header to specify the beta version(s) you want to use. - `(string & {})` - `"message-batches-2024-09-24" | "prompt-caching-2024-07-31" | "computer-use-2024-10-22" | 25 more` - `"message-batches-2024-09-24"` - `"prompt-caching-2024-07-31"` - `"computer-use-2024-10-22"` - `"computer-use-2025-01-24"` - `"pdfs-2024-09-25"` - `"token-counting-2024-11-01"` - `"token-efficient-tools-2025-02-19"` - `"output-128k-2025-02-19"` - `"files-api-2025-04-14"` - `"mcp-client-2025-04-04"` - `"mcp-client-2025-11-20"` - `"dev-full-thinking-2025-05-14"` - `"interleaved-thinking-2025-05-14"` - `"code-execution-2025-05-22"` - `"extended-cache-ttl-2025-04-11"` - `"context-1m-2025-08-07"` - `"context-management-2025-06-27"` - `"model-context-window-exceeded-2025-08-26"` - `"skills-2025-10-02"` - `"fast-mode-2026-02-01"` - `"output-300k-2026-03-24"` - `"user-profiles-2026-03-24"` - `"advisor-tool-2026-03-01"` - `"managed-agents-2026-04-01"` - `"cache-diagnosis-2026-04-07"` - `"thinking-token-count-2026-05-13"` - `"server-side-fallback-2026-06-01"` - `"fallback-credit-2026-06-01"` ### Returns - `ModelInfo` - `id: string` Unique model identifier. - `capabilities: ModelCapabilities | null` Model capability information. - `batch: CapabilitySupport` Whether the model supports the Batch API. - `supported: boolean` Whether this capability is supported by the model. - `citations: CapabilitySupport` Whether the model supports citation generation. - `code_execution: CapabilitySupport` Whether the model supports code execution tools. - `context_management: ContextManagementCapability` Context management support and available strategies. - `clear_thinking_20251015: CapabilitySupport | null` Indicates whether a capability is supported. - `clear_tool_uses_20250919: CapabilitySupport | null` Indicates whether a capability is supported. - `compact_20260112: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. - `effort: EffortCapability` Effort (reasoning_effort) support and available levels. - `high: CapabilitySupport` Whether the model supports high effort level. - `low: CapabilitySupport` Whether the model supports low effort level. - `max: CapabilitySupport` Whether the model supports max effort level. - `medium: CapabilitySupport` Whether the model supports medium effort level. - `supported: boolean` Whether this capability is supported by the model. - `xhigh: CapabilitySupport | null` Indicates whether a capability is supported. - `image_input: CapabilitySupport` Whether the model accepts image content blocks. - `pdf_input: CapabilitySupport` Whether the model accepts PDF content blocks. - `structured_outputs: CapabilitySupport` Whether the model supports structured output / JSON mode / strict tool schemas. - `thinking: ThinkingCapability` Thinking capability and supported type configurations. - `supported: boolean` Whether this capability is supported by the model. - `types: ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'. - `created_at: string` 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. - `display_name: string` A human-readable name for the model. - `max_input_tokens: number | null` Maximum input context window size in tokens for this model. - `max_tokens: number | null` Maximum value for the `max_tokens` parameter when using this model. - `type: "model"` Object type. For Models, this is always `"model"`. - `"model"` ### Example ```typescript import Anthropic from '@anthropic-ai/sdk'; const client = new Anthropic({ apiKey: process.env['ANTHROPIC_API_KEY'], // This is the default and can be omitted }); // Automatically fetches more pages as needed. for await (const modelInfo of client.models.list()) { console.log(modelInfo.id); } ``` #### 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 `client.models.retrieve(stringmodelID, ModelRetrieveParamsparams?, RequestOptionsoptions?): ModelInfo` **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 - `modelID: string` Model identifier or alias. - `params: ModelRetrieveParams` - `betas?: Array` Optional header to specify the beta version(s) you want to use. - `(string & {})` - `"message-batches-2024-09-24" | "prompt-caching-2024-07-31" | "computer-use-2024-10-22" | 25 more` - `"message-batches-2024-09-24"` - `"prompt-caching-2024-07-31"` - `"computer-use-2024-10-22"` - `"computer-use-2025-01-24"` - `"pdfs-2024-09-25"` - `"token-counting-2024-11-01"` - `"token-efficient-tools-2025-02-19"` - `"output-128k-2025-02-19"` - `"files-api-2025-04-14"` - `"mcp-client-2025-04-04"` - `"mcp-client-2025-11-20"` - `"dev-full-thinking-2025-05-14"` - `"interleaved-thinking-2025-05-14"` - `"code-execution-2025-05-22"` - `"extended-cache-ttl-2025-04-11"` - `"context-1m-2025-08-07"` - `"context-management-2025-06-27"` - `"model-context-window-exceeded-2025-08-26"` - `"skills-2025-10-02"` - `"fast-mode-2026-02-01"` - `"output-300k-2026-03-24"` - `"user-profiles-2026-03-24"` - `"advisor-tool-2026-03-01"` - `"managed-agents-2026-04-01"` - `"cache-diagnosis-2026-04-07"` - `"thinking-token-count-2026-05-13"` - `"server-side-fallback-2026-06-01"` - `"fallback-credit-2026-06-01"` ### Returns - `ModelInfo` - `id: string` Unique model identifier. - `capabilities: ModelCapabilities | null` Model capability information. - `batch: CapabilitySupport` Whether the model supports the Batch API. - `supported: boolean` Whether this capability is supported by the model. - `citations: CapabilitySupport` Whether the model supports citation generation. - `code_execution: CapabilitySupport` Whether the model supports code execution tools. - `context_management: ContextManagementCapability` Context management support and available strategies. - `clear_thinking_20251015: CapabilitySupport | null` Indicates whether a capability is supported. - `clear_tool_uses_20250919: CapabilitySupport | null` Indicates whether a capability is supported. - `compact_20260112: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. - `effort: EffortCapability` Effort (reasoning_effort) support and available levels. - `high: CapabilitySupport` Whether the model supports high effort level. - `low: CapabilitySupport` Whether the model supports low effort level. - `max: CapabilitySupport` Whether the model supports max effort level. - `medium: CapabilitySupport` Whether the model supports medium effort level. - `supported: boolean` Whether this capability is supported by the model. - `xhigh: CapabilitySupport | null` Indicates whether a capability is supported. - `image_input: CapabilitySupport` Whether the model accepts image content blocks. - `pdf_input: CapabilitySupport` Whether the model accepts PDF content blocks. - `structured_outputs: CapabilitySupport` Whether the model supports structured output / JSON mode / strict tool schemas. - `thinking: ThinkingCapability` Thinking capability and supported type configurations. - `supported: boolean` Whether this capability is supported by the model. - `types: ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'. - `created_at: string` 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. - `display_name: string` A human-readable name for the model. - `max_input_tokens: number | null` Maximum input context window size in tokens for this model. - `max_tokens: number | null` Maximum value for the `max_tokens` parameter when using this model. - `type: "model"` Object type. For Models, this is always `"model"`. - `"model"` ### Example ```typescript import Anthropic from '@anthropic-ai/sdk'; const client = new Anthropic({ apiKey: process.env['ANTHROPIC_API_KEY'], // This is the default and can be omitted }); const modelInfo = await client.models.retrieve('model_id'); console.log(modelInfo.id); ``` #### 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 - `CapabilitySupport` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. ### Context Management Capability - `ContextManagementCapability` Context management capability details. - `clear_thinking_20251015: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. - `clear_tool_uses_20250919: CapabilitySupport | null` Indicates whether a capability is supported. - `compact_20260112: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. ### Effort Capability - `EffortCapability` Effort (reasoning_effort) capability details. - `high: CapabilitySupport` Whether the model supports high effort level. - `supported: boolean` Whether this capability is supported by the model. - `low: CapabilitySupport` Whether the model supports low effort level. - `max: CapabilitySupport` Whether the model supports max effort level. - `medium: CapabilitySupport` Whether the model supports medium effort level. - `supported: boolean` Whether this capability is supported by the model. - `xhigh: CapabilitySupport | null` Indicates whether a capability is supported. ### Model Capabilities - `ModelCapabilities` Model capability information. - `batch: CapabilitySupport` Whether the model supports the Batch API. - `supported: boolean` Whether this capability is supported by the model. - `citations: CapabilitySupport` Whether the model supports citation generation. - `code_execution: CapabilitySupport` Whether the model supports code execution tools. - `context_management: ContextManagementCapability` Context management support and available strategies. - `clear_thinking_20251015: CapabilitySupport | null` Indicates whether a capability is supported. - `clear_tool_uses_20250919: CapabilitySupport | null` Indicates whether a capability is supported. - `compact_20260112: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. - `effort: EffortCapability` Effort (reasoning_effort) support and available levels. - `high: CapabilitySupport` Whether the model supports high effort level. - `low: CapabilitySupport` Whether the model supports low effort level. - `max: CapabilitySupport` Whether the model supports max effort level. - `medium: CapabilitySupport` Whether the model supports medium effort level. - `supported: boolean` Whether this capability is supported by the model. - `xhigh: CapabilitySupport | null` Indicates whether a capability is supported. - `image_input: CapabilitySupport` Whether the model accepts image content blocks. - `pdf_input: CapabilitySupport` Whether the model accepts PDF content blocks. - `structured_outputs: CapabilitySupport` Whether the model supports structured output / JSON mode / strict tool schemas. - `thinking: ThinkingCapability` Thinking capability and supported type configurations. - `supported: boolean` Whether this capability is supported by the model. - `types: ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'. ### Model Info - `ModelInfo` - `id: string` Unique model identifier. - `capabilities: ModelCapabilities | null` Model capability information. - `batch: CapabilitySupport` Whether the model supports the Batch API. - `supported: boolean` Whether this capability is supported by the model. - `citations: CapabilitySupport` Whether the model supports citation generation. - `code_execution: CapabilitySupport` Whether the model supports code execution tools. - `context_management: ContextManagementCapability` Context management support and available strategies. - `clear_thinking_20251015: CapabilitySupport | null` Indicates whether a capability is supported. - `clear_tool_uses_20250919: CapabilitySupport | null` Indicates whether a capability is supported. - `compact_20260112: CapabilitySupport | null` Indicates whether a capability is supported. - `supported: boolean` Whether this capability is supported by the model. - `effort: EffortCapability` Effort (reasoning_effort) support and available levels. - `high: CapabilitySupport` Whether the model supports high effort level. - `low: CapabilitySupport` Whether the model supports low effort level. - `max: CapabilitySupport` Whether the model supports max effort level. - `medium: CapabilitySupport` Whether the model supports medium effort level. - `supported: boolean` Whether this capability is supported by the model. - `xhigh: CapabilitySupport | null` Indicates whether a capability is supported. - `image_input: CapabilitySupport` Whether the model accepts image content blocks. - `pdf_input: CapabilitySupport` Whether the model accepts PDF content blocks. - `structured_outputs: CapabilitySupport` Whether the model supports structured output / JSON mode / strict tool schemas. - `thinking: ThinkingCapability` Thinking capability and supported type configurations. - `supported: boolean` Whether this capability is supported by the model. - `types: ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'. - `created_at: string` 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. - `display_name: string` A human-readable name for the model. - `max_input_tokens: number | null` Maximum input context window size in tokens for this model. - `max_tokens: number | null` Maximum value for the `max_tokens` parameter when using this model. - `type: "model"` Object type. For Models, this is always `"model"`. - `"model"` ### Thinking Capability - `ThinkingCapability` Thinking capability details. - `supported: boolean` Whether this capability is supported by the model. - `types: ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `supported: boolean` Whether this capability is supported by the model. - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'. ### Thinking Types - `ThinkingTypes` Supported thinking type configurations. - `adaptive: CapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `supported: boolean` Whether this capability is supported by the model. - `enabled: CapabilitySupport` Whether the model supports thinking with type 'enabled'.