List Session Threads

$ ant beta:sessions:threads list

GET/v1/sessions/{session_id}/threads

Parameters

--session-id: string

Path param: Path parameter session_id

--limit: optional number

Query param: Maximum results per page. Defaults to 1000.

formatint32

--page: optional string

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

--beta: optional array of AnthropicBeta

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

Returns

BetaManagedAgentsListSessionThreads: object{ data, next_page }

Paginated list of threads within a session.

data: optional array of BetaManagedAgentsSessionThread { id, agent, archived_at, 8 more }

Threads in the session, primary first then children in spawn order.

id: string

Unique identifier for this thread.

agent: BetaManagedAgentsSessionThreadAgent { id, description, mcp_servers, 7 more } or BetaManagedAgentsAdvisor { model, type }

The resolved agent a session thread runs: a saved-agent snapshot, the platform advisor entry, or an inline-defined (ephemeral) agent snapshot.

One of the following:

beta_managed_agents_session_thread_agent: object{ id, description, mcp_servers, 7 more }

Resolved agent definition for a single session_thread. Snapshot of the agent at thread creation time. The multiagent roster is not repeated here; read it from Session.agent.

beta_managed_agents_advisor: object{ model, type }

Platform advisor roster entry: a model the session's primary thread may consult mid-turn.

model: string

The advisor model id.

type: "advisor"

archived_at: string

A timestamp in RFC 3339 format

formatdate-time

created_at: string

A timestamp in RFC 3339 format

formatdate-time

parent_thread_id: string

Parent thread that spawned this thread. Null for the primary thread.

session_id: string

The session this thread belongs to.

stats: object{ active_seconds, duration_seconds, startup_seconds }

Timing statistics for a session thread.

active_seconds: optional number

Cumulative time in seconds the thread spent actively running. Excludes idle time.

formatdouble

duration_seconds: optional number

Elapsed time since thread creation in seconds. For archived threads, frozen at the final update.

formatdouble

startup_seconds: optional number

Time in seconds for the thread to begin running. Zero for child threads, which start immediately.

formatdouble

status: "running" or "idle" or "rescheduling" or "terminated"

SessionThreadStatus enum

One of the following:

"running"

"idle"

"rescheduling"

"terminated"

type: "session_thread"

updated_at: string

A timestamp in RFC 3339 format

formatdate-time

usage: object{ active_seconds, cache_creation, cache_read_input_tokens, 4 more }

Cumulative token usage for a session thread across all turns.

active_seconds: optional number

Cumulative time in seconds this thread spent in running status. Equal to stats.active_seconds; surfaced here so a thread's usage carries every quantity its cost is priced on.

formatdouble

cache_creation: optional object{ ephemeral_1h_input_tokens, ephemeral_5m_input_tokens }

Prompt-cache creation token usage broken down by cache lifetime.

ephemeral_1h_input_tokens: optional number

Tokens used to create 1-hour ephemeral cache entries.

formatint32

ephemeral_5m_input_tokens: optional number

Tokens used to create 5-minute ephemeral cache entries.

formatint32

cache_read_input_tokens: optional number

Total tokens read from prompt cache.

formatint32

input_tokens: optional number

Total input tokens consumed across all turns.

formatint32

list_cost: optional object{ amount, currency }

A monetary amount in a specific currency.

amount: string

Amount in minor units of the currency, as an integer decimal string with no leading zeros: "2500" is $25.00 and "50" is fifty cents. A string rather than a number so no float rounding is ever applied.

currency: "USD"

Uppercase ISO-4217 currency code. USD is the only currency currently supported; the accepted set is closed and grows only when a new currency is priced.

output_tokens: optional number

Total output tokens generated across all turns.

formatint32

server_tool_use: optional object{ web_fetch_requests, web_search_requests }

Cumulative count of server-executed tool invocations, broken down by tool.

web_fetch_requests: optional number

Number of server-executed web fetch requests.

formatint32

web_search_requests: optional number

Number of server-executed web search requests.

formatint32

next_page: optional string

Opaque cursor for the next page. Null when no more results.

List Session Threads

ant beta:sessions:threads list \
  --api-key my-anthropic-api-key \
  --session-id sesn_011CZkZAtmR3yMPDzynEDxu7

{
  "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="
}