Claude Platform Docs

List Models

beta.models.list(ModelListParams**kwargs) -> SyncPage[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
after_id: Optional[str]

ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately after this object.

before_id: Optional[str]

ID of the object to use as a cursor for pagination. When provided, returns the page of results immediately before this object.

limit: Optional[int]

Number of items to return per page.

Defaults to 20. Ranges from 1 to 1000.

default20
maximum1000
minimum1
betas: Optional[List[AnthropicBetaParam]]

Optional header to specify the beta version(s) you want to use.

One of the following:
str
Literal["message-batches-2024-09-24", "prompt-caching-2024-07-31", "computer-use-2024-10-22", 38 more]
One of the following:
"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"
"user-profiles-2026-08-18"
"advisor-tool-2026-03-01"
"managed-agents-2026-04-01"
"cache-diagnosis-2026-04-07"
"dreaming-2026-04-21"
"thinking-token-count-2026-05-13"
"server-side-fallback-2026-06-01"
"server-side-fallback-2026-07-01"
"fallback-credit-2026-06-01"
"fallback-credit-2026-07-01"
"agent-memory-2026-07-22"
"mid-conversation-tool-changes-2026-07-01"
"compact-2026-01-12"
"computer-use-2025-11-24"
"mcp-tunnels-2026-06-22"
"structured-outputs-2025-11-13"
"task-budgets-2026-03-13"
"thinking-display-updates-2026-08-18"
"ce-user-management-2026-07-13"
Returns
class BetaModelInfo: …
id: str

Unique model identifier.

allowed_fallback_models: Optional[List[str]]

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: Optional[BetaModelCapabilities]

Model capability information.

created_at: datetime

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.

formatdate-time
display_name: str

A human-readable name for the model.

max_input_tokens: Optional[int]

Maximum input context window size in tokens for this model.

max_tokens: Optional[int]

Maximum value for the max_tokens parameter when using this model.

type: Literal["model"]

Object type.

For Models, this is always "model".

defaultmodel

List Models

import os
from anthropic import Anthropic

client = Anthropic(
    api_key=os.environ.get(
        "ANTHROPIC_API_KEY"
    ),  # This is the default and can be omitted
)
page = client.beta.models.list()
page = page.data[0]
print(page.id)
{
  "data": [
    {
      "id": "claude-opus-5",
      "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": "2026-07-24T00:00:00Z",
      "display_name": "Claude Opus 5",
      "max_input_tokens": 0,
      "max_tokens": 0,
      "type": "model"
    }
  ],
  "first_id": "first_id",
  "has_more": true,
  "last_id": "last_id"
}
Returns Examples
{
  "data": [
    {
      "id": "claude-opus-5",
      "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": "2026-07-24T00:00:00Z",
      "display_name": "Claude Opus 5",
      "max_input_tokens": 0,
      "max_tokens": 0,
      "type": "model"
    }
  ],
  "first_id": "first_id",
  "has_more": true,
  "last_id": "last_id"
}