Claude Platform Docs

List Session Threads

beta.sessions.threads.list(session_id, **kwargs) -> PageCursor<BetaManagedAgentsSessionThread>
GET/v1/sessions/{session_id}/threads

List Session Threads

Parameters
session_id: String
limit: Integer

Maximum results per page. Defaults to 1000.

formatint32
page: String

Opaque pagination cursor from a previous response's next_page. Forward-only.

betas: Array[AnthropicBeta]

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

One of the following:
String = String
AnthropicBeta = :"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 BetaManagedAgentsSessionThread { id, agent, archived_at, 8 more }

An execution thread within a session. Each session has one primary thread plus zero or more child threads spawned by the coordinator.

List Session Threads

require "anthropic"

anthropic = Anthropic::Client.new(api_key: "my-anthropic-api-key")

page = anthropic.beta.sessions.threads.list("sesn_011CZkZAtmR3yMPDzynEDxu7")

puts(page)
{
  "data": [
    {
      "id": "sthr_011CZkZVWa6oIjw0rgXZpnBt",
      "agent": {
        "id": "agent_011CZkYqphY8vELVzwCUpqiQ",
        "description": "A focused research subagent.",
        "mcp_servers": [
          {
            "name": "example-mcp",
            "type": "url",
            "url": "https://example-server.modelcontextprotocol.io/sse"
          }
        ],
        "model": {
          "id": "claude-opus-5",
          "effort": {
            "type": "low"
          },
          "inference_geo": "inference_geo",
          "speed": "standard"
        },
        "name": "Researcher",
        "skills": [
          {
            "skill_id": "xlsx",
            "type": "anthropic",
            "version": "1"
          }
        ],
        "system": "You are a research subagent that gathers and summarises sources for the coordinating agent.",
        "tools": [
          {
            "configs": [
              {
                "enabled": true,
                "name": "bash",
                "permission_policy": {
                  "type": "always_allow"
                },
                "type": "bash"
              }
            ],
            "default_config": {
              "enabled": true,
              "permission_policy": {
                "type": "always_ask"
              }
            },
            "type": "agent_toolset_20260401"
          }
        ],
        "type": "agent",
        "version": 1
      },
      "archived_at": null,
      "created_at": "2026-03-15T10:00:00Z",
      "parent_thread_id": null,
      "session_id": "sesn_011CZkZAtmR3yMPDzynEDxu7",
      "stats": {
        "active_seconds": 0,
        "duration_seconds": 0,
        "startup_seconds": 0
      },
      "status": "idle",
      "type": "session_thread",
      "updated_at": "2026-03-15T10:00:00Z",
      "usage": {
        "active_seconds": 0,
        "cache_creation": {
          "ephemeral_1h_input_tokens": 0,
          "ephemeral_5m_input_tokens": 0
        },
        "cache_read_input_tokens": 0,
        "input_tokens": 0,
        "list_cost": {
          "amount": "2500",
          "currency": "USD"
        },
        "output_tokens": 0,
        "server_tool_use": {
          "web_fetch_requests": 0,
          "web_search_requests": 3
        }
      }
    }
  ],
  "next_page": "page_MjAyNS0wNS0xNFQwMDowMDowMFo="
}
Returns Examples
{
  "data": [
    {
      "id": "sthr_011CZkZVWa6oIjw0rgXZpnBt",
      "agent": {
        "id": "agent_011CZkYqphY8vELVzwCUpqiQ",
        "description": "A focused research subagent.",
        "mcp_servers": [
          {
            "name": "example-mcp",
            "type": "url",
            "url": "https://example-server.modelcontextprotocol.io/sse"
          }
        ],
        "model": {
          "id": "claude-opus-5",
          "effort": {
            "type": "low"
          },
          "inference_geo": "inference_geo",
          "speed": "standard"
        },
        "name": "Researcher",
        "skills": [
          {
            "skill_id": "xlsx",
            "type": "anthropic",
            "version": "1"
          }
        ],
        "system": "You are a research subagent that gathers and summarises sources for the coordinating agent.",
        "tools": [
          {
            "configs": [
              {
                "enabled": true,
                "name": "bash",
                "permission_policy": {
                  "type": "always_allow"
                },
                "type": "bash"
              }
            ],
            "default_config": {
              "enabled": true,
              "permission_policy": {
                "type": "always_ask"
              }
            },
            "type": "agent_toolset_20260401"
          }
        ],
        "type": "agent",
        "version": 1
      },
      "archived_at": null,
      "created_at": "2026-03-15T10:00:00Z",
      "parent_thread_id": null,
      "session_id": "sesn_011CZkZAtmR3yMPDzynEDxu7",
      "stats": {
        "active_seconds": 0,
        "duration_seconds": 0,
        "startup_seconds": 0
      },
      "status": "idle",
      "type": "session_thread",
      "updated_at": "2026-03-15T10:00:00Z",
      "usage": {
        "active_seconds": 0,
        "cache_creation": {
          "ephemeral_1h_input_tokens": 0,
          "ephemeral_5m_input_tokens": 0
        },
        "cache_read_input_tokens": 0,
        "input_tokens": 0,
        "list_cost": {
          "amount": "2500",
          "currency": "USD"
        },
        "output_tokens": 0,
        "server_tool_use": {
          "web_fetch_requests": 0,
          "web_search_requests": 3
        }
      }
    }
  ],
  "next_page": "page_MjAyNS0wNS0xNFQwMDowMDowMFo="
}