# Versions

## List Agent Versions

`VersionListPageResponse Beta.Agents.Versions.List(VersionListParamsparameters, CancellationTokencancellationToken = default)`

**get** `/v1/agents/{agent_id}/versions`

List Agent Versions

### Parameters

- `VersionListParams parameters`

  - `required string agentID`

    Path param: Path parameter agent_id

  - `Int limit`

    Query param: Maximum results per page. Default 20, maximum 100.

  - `string page`

    Query param: Opaque pagination cursor.

  - `IReadOnlyList<AnthropicBeta> betas`

    Header param: 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`

    - `"server-side-fallback-2026-06-01"ServerSideFallback2026_06_01`

    - `"fallback-credit-2026-06-01"FallbackCredit2026_06_01`

### Returns

- `class VersionListPageResponse:`

  Paginated list of agent versions.

  - `required IReadOnlyList<BetaManagedAgentsAgent> Data`

    Agent versions.

    - `required string ID`

    - `required DateTimeOffset? ArchivedAt`

      A timestamp in RFC 3339 format

    - `required DateTimeOffset CreatedAt`

      A timestamp in RFC 3339 format

    - `required string? Description`

    - `required IReadOnlyList<BetaManagedAgentsMcpServerUrlDefinition> McpServers`

      - `required string Name`

      - `required Type Type`

        - `"url"Url`

      - `required string Url`

    - `required IReadOnlyDictionary<string, string> Metadata`

    - `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-fable-5"ClaudeFable5`

          Next generation of intelligence for the hardest knowledge work and coding problems

        - `"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 BetaManagedAgentsMultiagent? Multiagent`

      Resolved coordinator topology with a concrete agent roster.

      - `required IReadOnlyList<BetaManagedAgentsAgentReference> Agents`

        Agents the coordinator may spawn as session threads, each resolved to a specific version.

        - `required string ID`

        - `required Type Type`

          - `"agent"Agent`

        - `required Int Version`

      - `required Type Type`

        - `"coordinator"Coordinator`

    - `required string Name`

    - `required IReadOnlyList<Skill> 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<Tool> Tools`

      - `class BetaManagedAgentsAgentToolset20260401:`

        - `required IReadOnlyList<BetaManagedAgentsAgentToolConfig> 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<BetaManagedAgentsMcpToolConfig> 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.

          - `JsonElement Type "object"constant`

          - `IReadOnlyDictionary<string, JsonElement>? Properties`

          - `IReadOnlyList<string>? Required`

        - `required string Name`

        - `required Type Type`

          - `"custom"Custom`

    - `required Type Type`

      - `"agent"Agent`

    - `required DateTimeOffset UpdatedAt`

      A timestamp in RFC 3339 format

    - `required Int Version`

      The agent's current version. Starts at 1 and increments when the agent is modified.

  - `string? NextPage`

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

### Example

```csharp
VersionListParams parameters = new()
{
    AgentID = "agent_011CZkYpogX7uDKUyvBTophP"
};

var page = await client.Beta.Agents.Versions.List(parameters);
await foreach (var item in page.Paginate())
{
    Console.WriteLine(item);
}
```

#### Response

```json
{
  "data": [
    {
      "id": "agent_011CZkYpogX7uDKUyvBTophP",
      "archived_at": null,
      "created_at": "2026-03-15T10:00:00Z",
      "description": "A general-purpose starter agent.",
      "mcp_servers": [
        {
          "name": "example-mcp",
          "type": "url",
          "url": "https://example-server.modelcontextprotocol.io/sse"
        }
      ],
      "metadata": {
        "foo": "bar"
      },
      "model": {
        "id": "claude-sonnet-4-6",
        "speed": "standard"
      },
      "multiagent": {
        "agents": [
          {
            "id": "agent_011CZkYqphY8vELVzwCUpqiQ",
            "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",
      "updated_at": "2026-03-15T10:00:00Z",
      "version": 1
    }
  ],
  "next_page": "next_page"
}
```
