Claude Platform Docs

Update Session

client.Beta.Sessions.Update(ctx, sessionID, params) (*BetaManagedAgentsSession, error)
POST/v1/sessions/{session_id}

Update Session

Parameters
sessionID string
params BetaSessionUpdateParams
Agent param.Field[BetaManagedAgentsSessionAgentUpdate] Optional

Body param: Mid-session agent configuration update. Only tools and mcp_servers are updatable. Full replacement: the provided array becomes the new value. To preserve existing entries, GET the session, modify the array, and POST it back.

Budget param.Field[BetaManagedAgentsBudgetLimit] Optional

Body param: A hard spend ceiling. The session stops issuing new model requests once the tracked list cost reaches max_list_cost.

Metadata param.Field[map[string, string]] Optional

Body param: Metadata patch. Set a key to a string to upsert it, or to null to delete it. Omit the field to preserve.

Title param.Field[string] Optional

Body param: Human-readable session title.

minLength1
maxLength500
VaultIDs param.Field[[]string] Optional

Body param: Vault IDs (vlt_*) to attach to the session. Not yet supported; requests setting this field are rejected. Reserved for future use.

Betas param.Field[[]AnthropicBeta] Optional

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

string
type AnthropicBeta string
One of the following:
const AnthropicBetaMessageBatches2024_09_24 AnthropicBeta = "message-batches-2024-09-24"
const AnthropicBetaPromptCaching2024_07_31 AnthropicBeta = "prompt-caching-2024-07-31"
const AnthropicBetaComputerUse2024_10_22 AnthropicBeta = "computer-use-2024-10-22"
const AnthropicBetaComputerUse2025_01_24 AnthropicBeta = "computer-use-2025-01-24"
const AnthropicBetaPDFs2024_09_25 AnthropicBeta = "pdfs-2024-09-25"
const AnthropicBetaTokenCounting2024_11_01 AnthropicBeta = "token-counting-2024-11-01"
const AnthropicBetaTokenEfficientTools2025_02_19 AnthropicBeta = "token-efficient-tools-2025-02-19"
const AnthropicBetaOutput128k2025_02_19 AnthropicBeta = "output-128k-2025-02-19"
const AnthropicBetaFilesAPI2025_04_14 AnthropicBeta = "files-api-2025-04-14"
const AnthropicBetaMCPClient2025_04_04 AnthropicBeta = "mcp-client-2025-04-04"
const AnthropicBetaMCPClient2025_11_20 AnthropicBeta = "mcp-client-2025-11-20"
const AnthropicBetaDevFullThinking2025_05_14 AnthropicBeta = "dev-full-thinking-2025-05-14"
const AnthropicBetaInterleavedThinking2025_05_14 AnthropicBeta = "interleaved-thinking-2025-05-14"
const AnthropicBetaCodeExecution2025_05_22 AnthropicBeta = "code-execution-2025-05-22"
const AnthropicBetaExtendedCacheTTL2025_04_11 AnthropicBeta = "extended-cache-ttl-2025-04-11"
const AnthropicBetaContext1m2025_08_07 AnthropicBeta = "context-1m-2025-08-07"
const AnthropicBetaContextManagement2025_06_27 AnthropicBeta = "context-management-2025-06-27"
const AnthropicBetaModelContextWindowExceeded2025_08_26 AnthropicBeta = "model-context-window-exceeded-2025-08-26"
const AnthropicBetaSkills2025_10_02 AnthropicBeta = "skills-2025-10-02"
const AnthropicBetaFastMode2026_02_01 AnthropicBeta = "fast-mode-2026-02-01"
const AnthropicBetaOutput300k2026_03_24 AnthropicBeta = "output-300k-2026-03-24"
const AnthropicBetaUserProfiles2026_03_24 AnthropicBeta = "user-profiles-2026-03-24"
const AnthropicBetaUserProfiles2026_08_18 AnthropicBeta = "user-profiles-2026-08-18"
const AnthropicBetaAdvisorTool2026_03_01 AnthropicBeta = "advisor-tool-2026-03-01"
const AnthropicBetaManagedAgents2026_04_01 AnthropicBeta = "managed-agents-2026-04-01"
const AnthropicBetaCacheDiagnosis2026_04_07 AnthropicBeta = "cache-diagnosis-2026-04-07"
const AnthropicBetaDreaming2026_04_21 AnthropicBeta = "dreaming-2026-04-21"
const AnthropicBetaThinkingTokenCount2026_05_13 AnthropicBeta = "thinking-token-count-2026-05-13"
const AnthropicBetaServerSideFallback2026_06_01 AnthropicBeta = "server-side-fallback-2026-06-01"
const AnthropicBetaServerSideFallback2026_07_01 AnthropicBeta = "server-side-fallback-2026-07-01"
const AnthropicBetaFallbackCredit2026_06_01 AnthropicBeta = "fallback-credit-2026-06-01"
const AnthropicBetaFallbackCredit2026_07_01 AnthropicBeta = "fallback-credit-2026-07-01"
const AnthropicBetaAgentMemory2026_07_22 AnthropicBeta = "agent-memory-2026-07-22"
const AnthropicBetaMidConversationToolChanges2026_07_01 AnthropicBeta = "mid-conversation-tool-changes-2026-07-01"
const AnthropicBetaCompact2026_01_12 AnthropicBeta = "compact-2026-01-12"
const AnthropicBetaComputerUse2025_11_24 AnthropicBeta = "computer-use-2025-11-24"
const AnthropicBetaMCPTunnels2026_06_22 AnthropicBeta = "mcp-tunnels-2026-06-22"
const AnthropicBetaStructuredOutputs2025_11_13 AnthropicBeta = "structured-outputs-2025-11-13"
const AnthropicBetaTaskBudgets2026_03_13 AnthropicBeta = "task-budgets-2026-03-13"
const AnthropicBetaThinkingDisplayUpdates2026_08_18 AnthropicBeta = "thinking-display-updates-2026-08-18"
const AnthropicBetaCEUserManagement2026_07_13 AnthropicBeta = "ce-user-management-2026-07-13"
Returns
type BetaManagedAgentsSession struct{…}

A Managed Agents session.

Update Session

package main

import (
	"context"
	"fmt"

	"github.com/anthropics/anthropic-sdk-go"
	"github.com/anthropics/anthropic-sdk-go/option"
)

func main() {
	client := anthropic.NewClient(
		option.WithAPIKey("my-anthropic-api-key"),
	)
	betaManagedAgentsSession, err := client.Beta.Sessions.Update(
		context.TODO(),
		"sesn_011CZkZAtmR3yMPDzynEDxu7",
		anthropic.BetaSessionUpdateParams{},
	)
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("%+v\n", betaManagedAgentsSession.ID)
}
{
  "id": "sesn_011CZkZAtmR3yMPDzynEDxu7",
  "agent": {
    "id": "agent_011CZkYpogX7uDKUyvBTophP",
    "description": "A general-purpose starter agent.",
    "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"
    },
    "multiagent": {
      "agents": [
        {
          "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
        }
      ],
      "type": "coordinator"
    },
    "name": "My First Agent",
    "skills": [
      {
        "skill_id": "xlsx",
        "type": "anthropic",
        "version": "1"
      },
      {
        "skill_id": "skill_011CZkZFNu9hAbo3jZPRgTlx",
        "type": "custom",
        "version": "2"
      }
    ],
    "system": "You are a general-purpose agent that can research, write code, run commands, and use connected tools to complete the user's task end to end.",
    "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,
  "budget": {
    "max_list_cost": {
      "amount": "2500",
      "currency": "USD"
    },
    "type": "limit"
  },
  "created_at": "2026-03-15T10:00:00Z",
  "environment_id": "env_011CZkZ9X2dpNyB7HsEFoRfW",
  "metadata": {},
  "outcome_evaluations": [
    {
      "completed_at": "2026-03-15T10:02:31Z",
      "description": "Produce a 2-page summary as summary.md",
      "explanation": "All five sections present with inline citations.",
      "iteration": 0,
      "outcome_id": "outc_011CZkZRSw2kEfs6ncTVljxP",
      "result": "satisfied",
      "type": "outcome_evaluation"
    }
  ],
  "resources": [
    {
      "id": "sesrsc_011CZkZBJq5dWxk9fVLNcPht",
      "created_at": "2026-03-15T10:00:00Z",
      "file_id": "file_011CNha8iCJcU1wXNR6q4V8w",
      "mount_path": "/uploads/receipt.pdf",
      "type": "file",
      "updated_at": "2026-03-15T10:00:00Z"
    },
    {
      "id": "sesrsc_011CZkZCKr6eXyl0gWMOdQiu",
      "created_at": "2026-03-15T10:00:00Z",
      "mount_path": "/workspace/example-repo",
      "type": "github_repository",
      "updated_at": "2026-03-15T10:00:00Z",
      "url": "https://github.com/example-org/example-repo",
      "checkout": {
        "name": "main",
        "type": "branch"
      }
    }
  ],
  "stats": {
    "active_seconds": 0,
    "duration_seconds": 0
  },
  "status": "idle",
  "title": "Order #1234 inquiry",
  "type": "session",
  "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
    }
  },
  "vault_ids": [
    "vlt_011CZkZDLs7fYzm1hXNPeRjv"
  ],
  "deployment_id": "deployment_id"
}
Returns Examples
{
  "id": "sesn_011CZkZAtmR3yMPDzynEDxu7",
  "agent": {
    "id": "agent_011CZkYpogX7uDKUyvBTophP",
    "description": "A general-purpose starter agent.",
    "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"
    },
    "multiagent": {
      "agents": [
        {
          "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
        }
      ],
      "type": "coordinator"
    },
    "name": "My First Agent",
    "skills": [
      {
        "skill_id": "xlsx",
        "type": "anthropic",
        "version": "1"
      },
      {
        "skill_id": "skill_011CZkZFNu9hAbo3jZPRgTlx",
        "type": "custom",
        "version": "2"
      }
    ],
    "system": "You are a general-purpose agent that can research, write code, run commands, and use connected tools to complete the user's task end to end.",
    "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,
  "budget": {
    "max_list_cost": {
      "amount": "2500",
      "currency": "USD"
    },
    "type": "limit"
  },
  "created_at": "2026-03-15T10:00:00Z",
  "environment_id": "env_011CZkZ9X2dpNyB7HsEFoRfW",
  "metadata": {},
  "outcome_evaluations": [
    {
      "completed_at": "2026-03-15T10:02:31Z",
      "description": "Produce a 2-page summary as summary.md",
      "explanation": "All five sections present with inline citations.",
      "iteration": 0,
      "outcome_id": "outc_011CZkZRSw2kEfs6ncTVljxP",
      "result": "satisfied",
      "type": "outcome_evaluation"
    }
  ],
  "resources": [
    {
      "id": "sesrsc_011CZkZBJq5dWxk9fVLNcPht",
      "created_at": "2026-03-15T10:00:00Z",
      "file_id": "file_011CNha8iCJcU1wXNR6q4V8w",
      "mount_path": "/uploads/receipt.pdf",
      "type": "file",
      "updated_at": "2026-03-15T10:00:00Z"
    },
    {
      "id": "sesrsc_011CZkZCKr6eXyl0gWMOdQiu",
      "created_at": "2026-03-15T10:00:00Z",
      "mount_path": "/workspace/example-repo",
      "type": "github_repository",
      "updated_at": "2026-03-15T10:00:00Z",
      "url": "https://github.com/example-org/example-repo",
      "checkout": {
        "name": "main",
        "type": "branch"
      }
    }
  ],
  "stats": {
    "active_seconds": 0,
    "duration_seconds": 0
  },
  "status": "idle",
  "title": "Order #1234 inquiry",
  "type": "session",
  "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
    }
  },
  "vault_ids": [
    "vlt_011CZkZDLs7fYzm1hXNPeRjv"
  ],
  "deployment_id": "deployment_id"
}