Skip to main content

AgentBuilderOptions

AgentBuilderOptions configures the Agent Builder. Pass it as MastraEditor.builder to enable the Builder UI, toggle visible surfaces, pin admin defaults, and opt into skill registries.

See the Configuration page for concepts and worked examples.

Usage example
Direct link to Usage example

src/mastra/index.ts
import { MastraEditor } from '@mastra/editor'

new MastraEditor({
  builder: {
    enabled: true,
    features: {
      agent: { browser: false },
    },
    configuration: {
      agent: {
        memory: { observationalMemory: true },
        models: {
          allowed: [
            { provider: 'openai', modelId: 'gpt-5.4-mini' },
            { provider: 'openai', modelId: 'gpt-5.4' },
            { provider: 'anthropic', modelId: 'claude-opus-4-7' },
          ],
        },
      },
    },
    registries: {
      skillsSh: { enabled: true },
    },
  },
})

Properties
Direct link to Properties

enabled?:

boolean
= true
Master switch. When false, the Builder UI is disabled and `MastraEditor.resolveBuilder()` returns undefined.

features?:

{ agent?: AgentFeatures }
UI toggles. Each key on `features.agent` defaults to true when omitted.
AgentFeatures

agent.tools?:

boolean
Show the tools tab in the agent editor.

agent.agents?:

boolean
Show the sub-agents picker in the agent editor.

agent.workflows?:

boolean
Show the workflows picker in the agent editor.

agent.skills?:

boolean
Show the skills tab and library for the agent.

agent.memory?:

boolean
Show the memory configuration in the agent editor.

agent.model?:

boolean
Show the model picker in the agent editor. When false, the admin-pinned default model applies.

agent.browser?:

boolean
Show the browser tab. Resolves to true only when a valid browser provider is registered on `MastraEditor.browsers`; otherwise it is downgraded to false and a warning is logged.

agent.avatarUpload?:

boolean
Allow end users to upload an avatar for stored agents.

agent.favorites?:

boolean
Show favorite agents and skills with per-user state and aggregate counts.

configuration?:

{ agent?: BuilderAgentDefaults }
Admin-pinned defaults applied to every Builder-created agent. End users cannot override these values. See the BuilderAgentDefaults reference for the full schema.

registries?:

{ skillsSh?: { enabled: boolean } }
Opt-in third-party skill registries. When no registry is enabled, the Builder hides registry browse UI.
{ skillsSh?: { enabled: boolean } }

skillsSh?:

{ enabled: boolean }
Enable the skills.sh registry. When enabled, the Builder shows registry browse UI for skills.sh skills.
{ enabled: boolean }

enabled:

boolean
Set to `true` to opt in. Defaults to `false`.
On this page