## List Models

`client.beta.models.list(ModelListParamsparams?, RequestOptionsoptions?): Page<BetaModelInfo>`

**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<AnthropicBeta>`

    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

- `BetaModelInfo`

  - `id: string`

    Unique model identifier.

  - `allowed_fallback_models: Array<string> | null`

    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 | null`

    Model capability information.

    - `batch: BetaCapabilitySupport`

      Whether the model supports the Batch API.

      - `supported: boolean`

        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 | null`

        Indicates whether a capability is supported.

      - `clear_tool_uses_20250919: BetaCapabilitySupport | null`

        Indicates whether a capability is supported.

      - `compact_20260112: BetaCapabilitySupport | null`

        Indicates whether a capability is supported.

      - `supported: boolean`

        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: boolean`

        Whether this capability is supported by the model.

      - `xhigh: BetaCapabilitySupport | null`

        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: boolean`

        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: 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 betaModelInfo of client.beta.models.list()) {
  console.log(betaModelInfo.id);
}
```

#### 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"
}
```
