## List Models `beta.models.list(**kwargs) -> 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 - `after_id: String` 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` ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately before this object. - `limit: Integer` Number of items to return per page. Defaults to `20`. Ranges from `1` to `1000`. - `betas: Array[AnthropicBeta]` Optional header to specify the beta version(s) you want to use. - `String = String` - `AnthropicBeta = :"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 - `class BetaModelInfo` - `id: String` Unique model identifier. - `allowed_fallback_models: Array[String]` 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. - `capabilities: BetaModelCapabilities` Model capability information. - `batch: BetaCapabilitySupport` Whether the model supports the Batch API. - `supported: bool` Whether this capability is supported by the model. - `citations: BetaCapabilitySupport` Whether the model supports citation generation. - `code_execution: BetaCapabilitySupport` Whether the model supports code execution tools. - `context_management: BetaContextManagementCapability` Context management support and available strategies. - `clear_thinking_20251015: BetaCapabilitySupport` Indicates whether a capability is supported. - `clear_tool_uses_20250919: BetaCapabilitySupport` Indicates whether a capability is supported. - `compact_20260112: BetaCapabilitySupport` Indicates whether a capability is supported. - `supported: bool` Whether this capability is supported by the model. - `effort: BetaEffortCapability` Effort (reasoning_effort) support and available levels. - `high: BetaCapabilitySupport` Whether the model supports high effort level. - `low: BetaCapabilitySupport` Whether the model supports low effort level. - `max: BetaCapabilitySupport` Whether the model supports max effort level. - `medium: BetaCapabilitySupport` Whether the model supports medium effort level. - `supported: bool` Whether this capability is supported by the model. - `xhigh: BetaCapabilitySupport` Indicates whether a capability is supported. - `image_input: BetaCapabilitySupport` Whether the model accepts image content blocks. - `pdf_input: BetaCapabilitySupport` Whether the model accepts PDF content blocks. - `structured_outputs: BetaCapabilitySupport` Whether the model supports structured output / JSON mode / strict tool schemas. - `thinking: BetaThinkingCapability` Thinking capability and supported type configurations. - `supported: bool` Whether this capability is supported by the model. - `types: BetaThinkingTypes` Supported thinking type configurations. - `adaptive: BetaCapabilitySupport` Whether the model supports thinking with type 'adaptive' (auto). - `enabled: BetaCapabilitySupport` Whether the model supports thinking with type 'enabled'. - `created_at: Time` 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: Integer` Maximum input context window size in tokens for this model. - `max_tokens: Integer` Maximum value for the `max_tokens` parameter when using this model. - `type: :model` Object type. For Models, this is always `"model"`. - `:model` ### Example ```ruby require "anthropic" anthropic = Anthropic::Client.new(api_key: "my-anthropic-api-key") page = anthropic.beta.models.list puts(page) ``` #### 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" } ```