## Create Agent

`beta.agents.create(**kwargs) -> BetaManagedAgentsAgent`

**post** `/v1/agents`

Create Agent

### Parameters

- `model: BetaManagedAgentsModel | BetaManagedAgentsModelConfigParams`

  Model identifier. Accepts the [model string](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison), e.g. `claude-opus-4-6`, or a `model_config` object for additional configuration control

  - `BetaManagedAgentsModel = :"claude-fable-5" | :"claude-opus-4-8" | :"claude-opus-4-7" | 8 more | String`

    The model that will power your agent.

    See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.

    - `BetaManagedAgentsModel = :"claude-fable-5" | :"claude-opus-4-8" | :"claude-opus-4-7" | 8 more`

      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"`

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

      - `:"claude-opus-4-8"`

        Frontier intelligence for long-running agents and coding

      - `:"claude-opus-4-7"`

        Frontier intelligence for long-running agents and coding

      - `:"claude-opus-4-6"`

        Most intelligent model for building agents and coding

      - `:"claude-sonnet-4-6"`

        Best combination of speed and intelligence

      - `:"claude-haiku-4-5"`

        Fastest model with near-frontier intelligence

      - `:"claude-haiku-4-5-20251001"`

        Fastest model with near-frontier intelligence

      - `:"claude-opus-4-5"`

        Premium model combining maximum intelligence with practical performance

      - `:"claude-opus-4-5-20251101"`

        Premium model combining maximum intelligence with practical performance

      - `:"claude-sonnet-4-5"`

        High-performance model for agents and coding

      - `:"claude-sonnet-4-5-20250929"`

        High-performance model for agents and coding

    - `String = String`

  - `class BetaManagedAgentsModelConfigParams`

    An object that defines additional configuration control over model use

    - `id: BetaManagedAgentsModel`

      The model that will power your agent.

      See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.

    - `speed: :standard | :fast`

      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`

      - `:fast`

- `name: String`

  Human-readable name for the agent.

- `description: String`

  Description of what the agent does.

- `mcp_servers: Array[BetaManagedAgentsURLMCPServerParams]`

  MCP servers this agent connects to. Maximum 20. Names must be unique within the array.

  - `name: String`

    Unique name for this server, referenced by mcp_toolset configurations. 1-255 characters.

  - `type: :url`

    - `:url`

  - `url: String`

    Endpoint URL for the MCP server.

- `metadata: Hash[Symbol, String]`

  Arbitrary key-value metadata. Maximum 16 pairs, keys up to 64 chars, values up to 512 chars.

- `multiagent: BetaManagedAgentsMultiagentParams`

  A coordinator topology: the session's primary thread orchestrates work by spawning session threads, each running an agent drawn from the `agents` roster.

  - `agents: Array[BetaManagedAgentsMultiagentRosterEntryParams]`

    Agents the coordinator may spawn as session threads. 1–20 entries. Each entry is an agent ID string, a versioned `{"type":"agent","id","version"}` reference, or `{"type":"self"}` to allow recursive self-invocation. Entries must reference distinct agents (after resolving `self` and string forms); at most one `self`. Referenced agents must exist, must not be archived, and must not themselves have `multiagent` set (depth limit 1).

    - `String = String`

    - `class BetaManagedAgentsAgentParams`

      Specification for an Agent. Provide a specific `version` or use the short-form `agent="agent_id"` for the most recent version

      - `id: String`

        The `agent` ID.

      - `type: :agent`

        - `:agent`

      - `version: Integer`

        The specific `agent` version to use. Omit to use the latest version. Must be at least 1 if specified.

    - `class BetaManagedAgentsMultiagentSelfParams`

      Sentinel roster entry meaning "the agent that owns this configuration". Resolved server-side to a concrete agent reference.

      - `type: :self`

        - `:self`

  - `type: :coordinator`

    - `:coordinator`

- `skills: Array[BetaManagedAgentsSkillParams]`

  Skills available to the agent.

  - `class BetaManagedAgentsAnthropicSkillParams`

    An Anthropic-managed skill.

    - `skill_id: String`

      Identifier of the Anthropic skill (e.g., "xlsx").

    - `type: :anthropic`

      - `:anthropic`

    - `version: String`

      Version to pin. Defaults to latest if omitted.

  - `class BetaManagedAgentsCustomSkillParams`

    A user-created custom skill.

    - `skill_id: String`

      Tagged ID of the custom skill (e.g., "skill_01XJ5...").

    - `type: :custom`

      - `:custom`

    - `version: String`

      Version to pin. Defaults to latest if omitted.

- `system_: String`

  System prompt for the agent.

- `tools: Array[BetaManagedAgentsAgentToolset20260401Params | BetaManagedAgentsMCPToolsetParams | BetaManagedAgentsCustomToolParams]`

  Tool configurations available to the agent. Maximum of 128 tools across all toolsets allowed.

  - `class BetaManagedAgentsAgentToolset20260401Params`

    Configuration for built-in agent tools. Use this to enable or disable groups of tools available to the agent.

    - `type: :agent_toolset_20260401`

      - `:agent_toolset_20260401`

    - `configs: Array[BetaManagedAgentsAgentToolConfigParams]`

      Per-tool configuration overrides.

      - `name: :bash | :edit | :read | 5 more`

        Built-in agent tool identifier.

        - `:bash`

        - `:edit`

        - `:read`

        - `:write`

        - `:glob`

        - `:grep`

        - `:web_fetch`

        - `:web_search`

      - `enabled: bool`

        Whether this tool is enabled and available to Claude. Overrides the default_config setting.

      - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

        Permission policy for tool execution.

        - `class BetaManagedAgentsAlwaysAllowPolicy`

          Tool calls are automatically approved without user confirmation.

          - `type: :always_allow`

            - `:always_allow`

        - `class BetaManagedAgentsAlwaysAskPolicy`

          Tool calls require user confirmation before execution.

          - `type: :always_ask`

            - `:always_ask`

    - `default_config: BetaManagedAgentsAgentToolsetDefaultConfigParams`

      Default configuration for all tools in a toolset.

      - `enabled: bool`

        Whether tools are enabled and available to Claude by default. Defaults to true if not specified.

      - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

        Permission policy for tool execution.

        - `class BetaManagedAgentsAlwaysAllowPolicy`

          Tool calls are automatically approved without user confirmation.

        - `class BetaManagedAgentsAlwaysAskPolicy`

          Tool calls require user confirmation before execution.

  - `class BetaManagedAgentsMCPToolsetParams`

    Configuration for tools from an MCP server defined in `mcp_servers`.

    - `mcp_server_name: String`

      Name of the MCP server. Must match a server name from the mcp_servers array. 1-255 characters.

    - `type: :mcp_toolset`

      - `:mcp_toolset`

    - `configs: Array[BetaManagedAgentsMCPToolConfigParams]`

      Per-tool configuration overrides.

      - `name: String`

        Name of the MCP tool to configure. 1-128 characters.

      - `enabled: bool`

        Whether this tool is enabled. Overrides the `default_config` setting.

      - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

        Permission policy for tool execution.

        - `class BetaManagedAgentsAlwaysAllowPolicy`

          Tool calls are automatically approved without user confirmation.

        - `class BetaManagedAgentsAlwaysAskPolicy`

          Tool calls require user confirmation before execution.

    - `default_config: BetaManagedAgentsMCPToolsetDefaultConfigParams`

      Default configuration for all tools from an MCP server.

      - `enabled: bool`

        Whether tools are enabled by default. Defaults to true if not specified.

      - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

        Permission policy for tool execution.

        - `class BetaManagedAgentsAlwaysAllowPolicy`

          Tool calls are automatically approved without user confirmation.

        - `class BetaManagedAgentsAlwaysAskPolicy`

          Tool calls require user confirmation before execution.

  - `class BetaManagedAgentsCustomToolParams`

    A custom tool that is executed by the API client rather than the agent. When the agent calls this tool, an `agent.custom_tool_use` event is emitted and the session goes idle, waiting for the client to provide the result via a `user.custom_tool_result` event.

    - `description: String`

      Description of what the tool does, shown to the agent to help it decide when to use the tool. 1-1024 characters.

    - `input_schema: BetaManagedAgentsCustomToolInputSchema`

      JSON Schema for custom tool input parameters.

      - `type: :object`

        - `:object`

      - `properties: Hash[Symbol, untyped]`

      - `required: Array[String]`

    - `name: String`

      Unique name for the tool. 1-128 characters; letters, digits, underscores, and hyphens.

    - `type: :custom`

      - `:custom`

- `betas: Array[AnthropicBeta]`

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

  - `String = String`

  - `AnthropicBeta = :"message-batches-2024-09-24" | :"prompt-caching-2024-07-31" | :"computer-use-2024-10-22" | 25 more`

    - `:"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"`

    - `:"advisor-tool-2026-03-01"`

    - `:"managed-agents-2026-04-01"`

    - `:"cache-diagnosis-2026-04-07"`

    - `:"thinking-token-count-2026-05-13"`

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

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

### Returns

- `class BetaManagedAgentsAgent`

  A Managed Agents `agent`.

  - `id: String`

  - `archived_at: Time`

    A timestamp in RFC 3339 format

  - `created_at: Time`

    A timestamp in RFC 3339 format

  - `description: String`

  - `mcp_servers: Array[BetaManagedAgentsMCPServerURLDefinition]`

    - `name: String`

    - `type: :url`

      - `:url`

    - `url: String`

  - `metadata: Hash[Symbol, String]`

  - `model: BetaManagedAgentsModelConfig`

    Model identifier and configuration.

    - `id: BetaManagedAgentsModel`

      The model that will power your agent.

      See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.

      - `BetaManagedAgentsModel = :"claude-fable-5" | :"claude-opus-4-8" | :"claude-opus-4-7" | 8 more`

        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"`

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

        - `:"claude-opus-4-8"`

          Frontier intelligence for long-running agents and coding

        - `:"claude-opus-4-7"`

          Frontier intelligence for long-running agents and coding

        - `:"claude-opus-4-6"`

          Most intelligent model for building agents and coding

        - `:"claude-sonnet-4-6"`

          Best combination of speed and intelligence

        - `:"claude-haiku-4-5"`

          Fastest model with near-frontier intelligence

        - `:"claude-haiku-4-5-20251001"`

          Fastest model with near-frontier intelligence

        - `:"claude-opus-4-5"`

          Premium model combining maximum intelligence with practical performance

        - `:"claude-opus-4-5-20251101"`

          Premium model combining maximum intelligence with practical performance

        - `:"claude-sonnet-4-5"`

          High-performance model for agents and coding

        - `:"claude-sonnet-4-5-20250929"`

          High-performance model for agents and coding

      - `String = String`

    - `speed: :standard | :fast`

      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`

      - `:fast`

  - `multiagent: BetaManagedAgentsMultiagent`

    Resolved coordinator topology with a concrete agent roster.

    - `agents: Array[BetaManagedAgentsAgentReference]`

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

      - `id: String`

      - `type: :agent`

        - `:agent`

      - `version: Integer`

    - `type: :coordinator`

      - `:coordinator`

  - `name: String`

  - `skills: Array[BetaManagedAgentsAnthropicSkill | BetaManagedAgentsCustomSkill]`

    - `class BetaManagedAgentsAnthropicSkill`

      A resolved Anthropic-managed skill.

      - `skill_id: String`

      - `type: :anthropic`

        - `:anthropic`

      - `version: String`

    - `class BetaManagedAgentsCustomSkill`

      A resolved user-created custom skill.

      - `skill_id: String`

      - `type: :custom`

        - `:custom`

      - `version: String`

  - `system_: String`

  - `tools: Array[BetaManagedAgentsAgentToolset20260401 | BetaManagedAgentsMCPToolset | BetaManagedAgentsCustomTool]`

    - `class BetaManagedAgentsAgentToolset20260401`

      - `configs: Array[BetaManagedAgentsAgentToolConfig]`

        - `enabled: bool`

        - `name: :bash | :edit | :read | 5 more`

          Built-in agent tool identifier.

          - `:bash`

          - `:edit`

          - `:read`

          - `:write`

          - `:glob`

          - `:grep`

          - `:web_fetch`

          - `:web_search`

        - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

          Permission policy for tool execution.

          - `class BetaManagedAgentsAlwaysAllowPolicy`

            Tool calls are automatically approved without user confirmation.

            - `type: :always_allow`

              - `:always_allow`

          - `class BetaManagedAgentsAlwaysAskPolicy`

            Tool calls require user confirmation before execution.

            - `type: :always_ask`

              - `:always_ask`

      - `default_config: BetaManagedAgentsAgentToolsetDefaultConfig`

        Resolved default configuration for agent tools.

        - `enabled: bool`

        - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

          Permission policy for tool execution.

          - `class BetaManagedAgentsAlwaysAllowPolicy`

            Tool calls are automatically approved without user confirmation.

          - `class BetaManagedAgentsAlwaysAskPolicy`

            Tool calls require user confirmation before execution.

      - `type: :agent_toolset_20260401`

        - `:agent_toolset_20260401`

    - `class BetaManagedAgentsMCPToolset`

      - `configs: Array[BetaManagedAgentsMCPToolConfig]`

        - `enabled: bool`

        - `name: String`

        - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

          Permission policy for tool execution.

          - `class BetaManagedAgentsAlwaysAllowPolicy`

            Tool calls are automatically approved without user confirmation.

          - `class BetaManagedAgentsAlwaysAskPolicy`

            Tool calls require user confirmation before execution.

      - `default_config: BetaManagedAgentsMCPToolsetDefaultConfig`

        Resolved default configuration for all tools from an MCP server.

        - `enabled: bool`

        - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy | BetaManagedAgentsAlwaysAskPolicy`

          Permission policy for tool execution.

          - `class BetaManagedAgentsAlwaysAllowPolicy`

            Tool calls are automatically approved without user confirmation.

          - `class BetaManagedAgentsAlwaysAskPolicy`

            Tool calls require user confirmation before execution.

      - `mcp_server_name: String`

      - `type: :mcp_toolset`

        - `:mcp_toolset`

    - `class BetaManagedAgentsCustomTool`

      A custom tool as returned in API responses.

      - `description: String`

      - `input_schema: BetaManagedAgentsCustomToolInputSchema`

        JSON Schema for custom tool input parameters.

        - `type: :object`

          - `:object`

        - `properties: Hash[Symbol, untyped]`

        - `required: Array[String]`

      - `name: String`

      - `type: :custom`

        - `:custom`

  - `type: :agent`

    - `:agent`

  - `updated_at: Time`

    A timestamp in RFC 3339 format

  - `version: Integer`

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

### Example

```ruby
require "anthropic"

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

beta_managed_agents_agent = anthropic.beta.agents.create(model: :"claude-sonnet-4-6", name: "My First Agent")

puts(beta_managed_agents_agent)
```

#### Response

```json
{
  "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
}
```
