> ## Documentation Index
> Fetch the complete documentation index at: https://docs.labelbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# List the caller-defined metadata keys sessions carry

> Returns the distinct caller-defined metadata keys across every session the caller may list, sorted, so a client can offer them as filter choices without knowing them in advance. Sessions the caller's access policy hides contribute nothing. Capped at 200 keys; truncated reports when the cap was hit. Pair with listSessionMetadataValues, then filter listSessions with metadata or metadata_key.



## OpenAPI

````yaml /managed-agents/openapi.yaml get /managed-agents/v1/sessions/metadata-keys
openapi: 3.1.0
info:
  title: Managed Agents API
  version: 0.13.0
  description: >-
    The Recursion Managed Agents REST API. Authenticate with a Recursion API key
    as a bearer token. An organization-scoped key acts in its own organization
    and needs nothing else; a tenant-scoped key must also send
    `x-organization-id` with an organization id or `default`. Field names follow
    each operation's published schema.
servers:
  - url: https://api.recursion.labelbox.com
security:
  - bearerAuth: []
paths:
  /managed-agents/v1/sessions/metadata-keys:
    get:
      tags:
        - Sessions
      summary: List the caller-defined metadata keys sessions carry
      description: >-
        Returns the distinct caller-defined metadata keys across every session
        the caller may list, sorted, so a client can offer them as filter
        choices without knowing them in advance. Sessions the caller's access
        policy hides contribute nothing. Capped at 200 keys; truncated reports
        when the cap was hit. Pair with listSessionMetadataValues, then filter
        listSessions with metadata or metadata_key.
      operationId: managedAgentsListSessionMetadataKeys
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsSessionMetadataKeysResponse'
          description: >-
            Response body of GET /v1/sessions/metadata-keys: the distinct
            caller-defined metadata keys across the sessions the caller may
            list.
        '400':
          description: The request was rejected by schema or semantic validation.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiError'
        '401':
          description: The caller is unauthenticated.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiError'
        '403':
          description: The caller lacks a required permission or capability.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiErrorForbidden'
        '429':
          headers:
            Retry-After:
              description: Seconds the caller should wait before retrying.
              schema:
                type: string
              style: simple
          description: A rate limit is exhausted. Honor `Retry-After`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiError'
        '500':
          description: An unexpected server-side failure.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiError'
        '502':
          description: The service returned an invalid response.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiErrorBadGateway'
        '503':
          headers:
            Retry-After:
              description: Seconds the caller should wait before retrying.
              schema:
                type: string
              style: simple
          description: A dependency is unavailable. Retryable.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiError'
        '504':
          headers:
            Retry-After:
              description: When to retry, as delay seconds or an HTTP date.
              schema:
                type: string
          description: The service did not respond before the timeout. Retryable.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ManagedAgentsApiErrorGatewayTimeout'
components:
  schemas:
    ManagedAgentsSessionMetadataKeysResponse:
      description: >-
        Response body of GET /v1/sessions/metadata-keys: the distinct
        caller-defined metadata keys across the sessions the caller may list.
      properties:
        keys:
          description: >-
            Distinct caller-defined metadata keys carried by sessions the caller
            may list, sorted. Always an array; empty when no listed session
            carries metadata.
          items:
            type: string
          type: array
        truncated:
          description: >-
            True when the organization carries more distinct keys than the
            response holds. The list is sorted, so the missing keys sort after
            the last one returned.
          type: boolean
      required:
        - keys
      type: object
      example:
        keys:
          - example
        truncated: true
    ManagedAgentsApiError:
      type: object
      properties:
        code:
          type: string
          minLength: 1
          description: Stable machine-readable error code.
          enum:
            - analytics
            - analytics_not_ready
            - artifact_fetch_unavailable
            - artifact_generation_mismatch
            - artifact_hash_mismatch
            - artifact_invalid_events
            - artifact_invalid_json
            - artifact_not_allowlisted
            - artifact_size_mismatch
            - atomic_ingest_timeout
            - auth_unavailable
            - automation_event_source_invalid
            - automation_memory_unavailable
            - automation_reference_invalid
            - automation_runs_unconfigured
            - automations_unconfigured
            - bad_gateway
            - built_in_catalog_unavailable
            - built_in_integrations_unconfigured
            - compute_offerings_unavailable
            - conflict
            - content_store_request_canceled
            - content_store_unavailable
            - content_store_upload_timeout
            - credential_encryption_unconfigured
            - delegate_preparation_failed
            - entity_family_not_permitted
            - environment_not_verified
            - evaluation_cancellation_pending
            - evaluation_deletion_pending
            - event_admission_unavailable
            - event_ingress_unavailable
            - event_source_verification_credential_invalid
            - event_sources_unconfigured
            - execution_unconfigured
            - file_quota_exceeded
            - file_storage_unconfigured
            - forbidden
            - gateway_timeout
            - gestalt_unconfigured
            - github_rate_limited
            - github_unavailable
            - handoff_access_invalid
            - handoff_access_unavailable
            - handoff_access_unsupported
            - handoff_capture_unavailable
            - handoff_requires_retest
            - handoff_revoke_unavailable
            - handoff_signal_unavailable
            - idempotency_conflict
            - idempotency_in_progress
            - idempotency_unavailable
            - ingest_policy_changed
            - ingest_policy_not_found
            - ingest_policy_revoked
            - integrations_unconfigured
            - internal_error
            - invalid_json
            - invalid_pull_request_review_result
            - invalid_request
            - invalid_scope
            - invariant_violation
            - live_fleet_unconfigured
            - managed_agents_unavailable
            - missing_dependency
            - model_gateway_metadata_missing
            - model_gateway_unconfigured
            - model_gateway_unreachable
            - mutation_transaction_budget_exceeded
            - not_found
            - page_token_expired
            - payload_too_large
            - persistence_busy
            - precondition_failed
            - precondition_required
            - provider_registration_unsupported
            - provider_selection_unsupported
            - rate_limit_exceeded
            - rate_limited
            - repository_automation_unconfigured
            - request_too_large
            - reserved_source_type
            - revision_conflict
            - run_log_store_unavailable
            - runner_image_resolution_failed
            - sandbox_provider_disabled
            - service_unavailable
            - session_analyst_busy
            - session_analyst_model_unavailable
            - session_analyst_unconfigured
            - session_start_admission_unavailable
            - session_start_not_admitted
            - setup_fallback_environment_unsafe
            - setup_run_finished
            - setup_run_in_progress
            - setup_run_limit
            - setup_run_not_started
            - setup_runs_unavailable
            - skill_storage_unconfigured
            - slack_channels_rejected
            - slack_channels_unavailable
            - slack_channels_unconfigured
            - slack_connection_malformed
            - slack_event_intake_unavailable
            - slack_installation_mismatch
            - slack_missing_scope
            - slack_rate_limited
            - slack_reapproval_required
            - source_ownership_mismatch
            - source_revision_conflict
            - spanner_unavailable
            - streaming_unsupported
            - submission_transaction_budget_exceeded
            - task_version_number_conflict
            - team_board_unconfigured
            - too_many_streams
            - unauthorized
            - unsupported_media_type
            - vault_creation_retired
            - version_content_conflict
            - webhook_delivery_too_large
            - workspace_boundary_denied
        message:
          type: string
          minLength: 1
          description: Human-readable error message.
        details:
          description: Optional structured error details.
          type: object
          propertyNames:
            type: string
          additionalProperties: {}
      required:
        - code
        - message
      additionalProperties: false
      description: Standard flat error response.
    ManagedAgentsApiErrorForbidden:
      type: object
      properties:
        code:
          type: string
          minLength: 1
          description: Stable machine-readable error code.
          enum:
            - forbidden
        message:
          type: string
          minLength: 1
          description: Human-readable error message.
        details:
          description: Optional structured error details.
          type: object
          propertyNames:
            type: string
          additionalProperties: {}
      required:
        - code
        - message
      additionalProperties: false
      description: Standard flat error response.
    ManagedAgentsApiErrorBadGateway:
      type: object
      properties:
        code:
          type: string
          minLength: 1
          description: Stable machine-readable error code.
          enum:
            - bad_gateway
        message:
          type: string
          minLength: 1
          description: Human-readable error message.
        details:
          description: Optional structured error details.
          type: object
          propertyNames:
            type: string
          additionalProperties: {}
      required:
        - code
        - message
      additionalProperties: false
      description: Standard flat error response.
    ManagedAgentsApiErrorGatewayTimeout:
      type: object
      properties:
        code:
          type: string
          minLength: 1
          description: Stable machine-readable error code.
          enum:
            - gateway_timeout
        message:
          type: string
          minLength: 1
          description: Human-readable error message.
        details:
          description: Optional structured error details.
          type: object
          propertyNames:
            type: string
          additionalProperties: {}
      required:
        - code
        - message
      additionalProperties: false
      description: Standard flat error response.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: A Recursion API key, created in the console under API keys.

````