## Get Session `BetaManagedAgentsSession Beta.Sessions.Retrieve(SessionRetrieveParamsparameters, CancellationTokencancellationToken = default)` **get** `/v1/sessions/{session_id}` Get Session ### Parameters - `SessionRetrieveParams parameters` - `required string sessionID` Path parameter session_id - `IReadOnlyList betas` Optional header to specify the beta version(s) you want to use. - `"message-batches-2024-09-24"MessageBatches2024_09_24` - `"prompt-caching-2024-07-31"PromptCaching2024_07_31` - `"computer-use-2024-10-22"ComputerUse2024_10_22` - `"computer-use-2025-01-24"ComputerUse2025_01_24` - `"pdfs-2024-09-25"Pdfs2024_09_25` - `"token-counting-2024-11-01"TokenCounting2024_11_01` - `"token-efficient-tools-2025-02-19"TokenEfficientTools2025_02_19` - `"output-128k-2025-02-19"Output128k2025_02_19` - `"files-api-2025-04-14"FilesApi2025_04_14` - `"mcp-client-2025-04-04"McpClient2025_04_04` - `"mcp-client-2025-11-20"McpClient2025_11_20` - `"dev-full-thinking-2025-05-14"DevFullThinking2025_05_14` - `"interleaved-thinking-2025-05-14"InterleavedThinking2025_05_14` - `"code-execution-2025-05-22"CodeExecution2025_05_22` - `"extended-cache-ttl-2025-04-11"ExtendedCacheTtl2025_04_11` - `"context-1m-2025-08-07"Context1m2025_08_07` - `"context-management-2025-06-27"ContextManagement2025_06_27` - `"model-context-window-exceeded-2025-08-26"ModelContextWindowExceeded2025_08_26` - `"skills-2025-10-02"Skills2025_10_02` - `"fast-mode-2026-02-01"FastMode2026_02_01` - `"output-300k-2026-03-24"Output300k2026_03_24` - `"user-profiles-2026-03-24"UserProfiles2026_03_24` - `"advisor-tool-2026-03-01"AdvisorTool2026_03_01` - `"managed-agents-2026-04-01"ManagedAgents2026_04_01` - `"cache-diagnosis-2026-04-07"CacheDiagnosis2026_04_07` - `"thinking-token-count-2026-05-13"ThinkingTokenCount2026_05_13` ### Returns - `class BetaManagedAgentsSession:` A Managed Agents `session`. - `required string ID` - `required BetaManagedAgentsSessionAgent Agent` Resolved `agent` definition for a `session`. Snapshot of the `agent` at `session` creation time. - `required string ID` - `required string? Description` - `required IReadOnlyList McpServers` - `required string Name` - `required Type Type` - `"url"Url` - `required string Url` - `required BetaManagedAgentsModelConfig Model` Model identifier and configuration. - `required BetaManagedAgentsModel ID` The model that will power your agent. See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options. - `"claude-opus-4-8"ClaudeOpus4_8` Frontier intelligence for long-running agents and coding - `"claude-opus-4-7"ClaudeOpus4_7` Frontier intelligence for long-running agents and coding - `"claude-opus-4-6"ClaudeOpus4_6` Most intelligent model for building agents and coding - `"claude-sonnet-4-6"ClaudeSonnet4_6` Best combination of speed and intelligence - `"claude-haiku-4-5"ClaudeHaiku4_5` Fastest model with near-frontier intelligence - `"claude-haiku-4-5-20251001"ClaudeHaiku4_5_20251001` Fastest model with near-frontier intelligence - `"claude-opus-4-5"ClaudeOpus4_5` Premium model combining maximum intelligence with practical performance - `"claude-opus-4-5-20251101"ClaudeOpus4_5_20251101` Premium model combining maximum intelligence with practical performance - `"claude-sonnet-4-5"ClaudeSonnet4_5` High-performance model for agents and coding - `"claude-sonnet-4-5-20250929"ClaudeSonnet4_5_20250929` High-performance model for agents and coding - `Speed Speed` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `"standard"Standard` - `"fast"Fast` - `required BetaManagedAgentsSessionMultiagentCoordinator? Multiagent` Resolved coordinator topology with full agent definitions for each roster member. - `required IReadOnlyList Agents` Full `agent` definitions the coordinator may spawn as session threads. - `required string ID` - `required string? Description` - `required IReadOnlyList McpServers` - `required string Name` - `required Type Type` - `required string Url` - `required BetaManagedAgentsModelConfig Model` Model identifier and configuration. - `required string Name` - `required IReadOnlyList Skills` - `class BetaManagedAgentsAnthropicSkill:` A resolved Anthropic-managed skill. - `required string SkillID` - `required Type Type` - `"anthropic"Anthropic` - `required string Version` - `class BetaManagedAgentsCustomSkill:` A resolved user-created custom skill. - `required string SkillID` - `required Type Type` - `"custom"Custom` - `required string Version` - `required string? System` - `required IReadOnlyList Tools` - `class BetaManagedAgentsAgentToolset20260401:` - `required IReadOnlyList Configs` - `required Boolean Enabled` - `required Name Name` Built-in agent tool identifier. - `"bash"Bash` - `"edit"Edit` - `"read"Read` - `"write"Write` - `"glob"Glob` - `"grep"Grep` - `"web_fetch"WebFetch` - `"web_search"WebSearch` - `required PermissionPolicy PermissionPolicy` Permission policy for tool execution. - `class BetaManagedAgentsAlwaysAllowPolicy:` Tool calls are automatically approved without user confirmation. - `required Type Type` - `"always_allow"AlwaysAllow` - `class BetaManagedAgentsAlwaysAskPolicy:` Tool calls require user confirmation before execution. - `required Type Type` - `"always_ask"AlwaysAsk` - `required BetaManagedAgentsAgentToolsetDefaultConfig DefaultConfig` Resolved default configuration for agent tools. - `required Boolean Enabled` - `required PermissionPolicy PermissionPolicy` Permission policy for tool execution. - `class BetaManagedAgentsAlwaysAllowPolicy:` Tool calls are automatically approved without user confirmation. - `class BetaManagedAgentsAlwaysAskPolicy:` Tool calls require user confirmation before execution. - `required Type Type` - `"agent_toolset_20260401"AgentToolset20260401` - `class BetaManagedAgentsMcpToolset:` - `required IReadOnlyList Configs` - `required Boolean Enabled` - `required string Name` - `required PermissionPolicy PermissionPolicy` Permission policy for tool execution. - `class BetaManagedAgentsAlwaysAllowPolicy:` Tool calls are automatically approved without user confirmation. - `class BetaManagedAgentsAlwaysAskPolicy:` Tool calls require user confirmation before execution. - `required BetaManagedAgentsMcpToolsetDefaultConfig DefaultConfig` Resolved default configuration for all tools from an MCP server. - `required Boolean Enabled` - `required PermissionPolicy PermissionPolicy` Permission policy for tool execution. - `class BetaManagedAgentsAlwaysAllowPolicy:` Tool calls are automatically approved without user confirmation. - `class BetaManagedAgentsAlwaysAskPolicy:` Tool calls require user confirmation before execution. - `required string McpServerName` - `required Type Type` - `"mcp_toolset"McpToolset` - `class BetaManagedAgentsCustomTool:` A custom tool as returned in API responses. - `required string Description` - `required BetaManagedAgentsCustomToolInputSchema InputSchema` JSON Schema for custom tool input parameters. - `IReadOnlyDictionary? Properties` JSON Schema properties defining the tool's input parameters. - `IReadOnlyList Required` List of required property names. - `Type Type` Must be 'object' for tool input schemas. - `"object"Object` - `required string Name` - `required Type Type` - `"custom"Custom` - `required Type Type` - `"agent"Agent` - `required Int Version` - `required Type Type` - `"coordinator"Coordinator` - `required string Name` - `required IReadOnlyList Skills` - `class BetaManagedAgentsAnthropicSkill:` A resolved Anthropic-managed skill. - `class BetaManagedAgentsCustomSkill:` A resolved user-created custom skill. - `required string? System` - `required IReadOnlyList Tools` - `class BetaManagedAgentsAgentToolset20260401:` - `class BetaManagedAgentsMcpToolset:` - `class BetaManagedAgentsCustomTool:` A custom tool as returned in API responses. - `required Type Type` - `"agent"Agent` - `required Int Version` - `required DateTimeOffset? ArchivedAt` A timestamp in RFC 3339 format - `required DateTimeOffset CreatedAt` A timestamp in RFC 3339 format - `required string EnvironmentID` - `required IReadOnlyDictionary Metadata` - `required IReadOnlyList OutcomeEvaluations` Per-outcome evaluation state. One entry per define_outcome event sent to the session. - `required DateTimeOffset? CompletedAt` A timestamp in RFC 3339 format - `required string Description` What the agent should produce. - `required string? Explanation` Grader's verdict text from the most recent evaluation. For satisfied, explains why criteria are met; for needs_revision (intermediate), what's missing; for failed, why unrecoverable. - `required Int Iteration` 0-indexed revision cycle the outcome is currently on. - `required string OutcomeID` Server-generated outc_ ID for this outcome. - `required string Result` Current evaluation state. `pending` before the agent begins work; `running` while producing or revising; `evaluating` while the grader scores; `satisfied`/`max_iterations_reached`/`failed`/`interrupted` are terminal. - `required Type Type` - `"outcome_evaluation"OutcomeEvaluation` - `required IReadOnlyList Resources` - `class BetaManagedAgentsGitHubRepositoryResource:` - `required string ID` - `required DateTimeOffset CreatedAt` A timestamp in RFC 3339 format - `required string MountPath` - `required Type Type` - `"github_repository"GitHubRepository` - `required DateTimeOffset UpdatedAt` A timestamp in RFC 3339 format - `required string Url` - `Checkout? Checkout` - `class BetaManagedAgentsBranchCheckout:` - `required string Name` Branch name to check out. - `required Type Type` - `"branch"Branch` - `class BetaManagedAgentsCommitCheckout:` - `required string Sha` Full commit SHA to check out. - `required Type Type` - `"commit"Commit` - `class BetaManagedAgentsFileResource:` - `required string ID` - `required DateTimeOffset CreatedAt` A timestamp in RFC 3339 format - `required string FileID` - `required string MountPath` - `required Type Type` - `"file"File` - `required DateTimeOffset UpdatedAt` A timestamp in RFC 3339 format - `class BetaManagedAgentsMemoryStoreResource:` A memory store attached to an agent session. - `required string MemoryStoreID` The memory store ID (memstore_...). Must belong to the caller's organization and workspace. - `required Type Type` - `"memory_store"MemoryStore` - `Access? Access` Access mode for an attached memory store. - `"read_write"ReadWrite` - `"read_only"ReadOnly` - `string Description` Description of the memory store, snapshotted at attach time. Rendered into the agent's system prompt. Empty string when the store has no description. - `string? Instructions` Per-attachment guidance for the agent on how to use this store. Rendered into the memory section of the system prompt. Max 4096 chars. - `string? MountPath` Filesystem path where the store is mounted in the session container, e.g. /mnt/memory/user-preferences. Derived from the store's name. Output-only. - `string? Name` Display name of the memory store, snapshotted at attach time. Later edits to the store's name do not propagate to this resource. - `required BetaManagedAgentsSessionStats Stats` Timing statistics for a session. - `Double ActiveSeconds` Cumulative time in seconds the session spent in running status. Excludes idle time. - `Double DurationSeconds` Elapsed time since session creation in seconds. For terminated sessions, frozen at the final update. - `required Status Status` SessionStatus enum - `"rescheduling"Rescheduling` - `"running"Running` - `"idle"Idle` - `"terminated"Terminated` - `required string? Title` - `required Type Type` - `"session"Session` - `required DateTimeOffset UpdatedAt` A timestamp in RFC 3339 format - `required BetaManagedAgentsSessionUsage Usage` Cumulative token usage for a session across all turns. - `BetaManagedAgentsCacheCreationUsage CacheCreation` Prompt-cache creation token usage broken down by cache lifetime. - `Int Ephemeral1hInputTokens` Tokens used to create 1-hour ephemeral cache entries. - `Int Ephemeral5mInputTokens` Tokens used to create 5-minute ephemeral cache entries. - `Int CacheReadInputTokens` Total tokens read from prompt cache. - `Int InputTokens` Total input tokens consumed across all turns. - `Int OutputTokens` Total output tokens generated across all turns. - `required IReadOnlyList VaultIds` Vault IDs attached to the session at creation. Empty when no vaults were supplied. ### Example ```csharp SessionRetrieveParams parameters = new() { SessionID = "sesn_011CZkZAtmR3yMPDzynEDxu7" }; var betaManagedAgentsSession = await client.Beta.Sessions.Retrieve(parameters); Console.WriteLine(betaManagedAgentsSession); ``` #### Response ```json { "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-sonnet-4-6", "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-sonnet-4-6", "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" } } ], "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" } } ], "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", "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": { "cache_creation": { "ephemeral_1h_input_tokens": 0, "ephemeral_5m_input_tokens": 0 }, "cache_read_input_tokens": 0, "input_tokens": 0, "output_tokens": 0 }, "vault_ids": [ "vlt_011CZkZDLs7fYzm1hXNPeRjv" ] } ```