What causes "User must be associated to rubric before LLM generation" in instructure/canvas-lms?

Ensure the rubric is created in a user context so user_id is set before enabling LLM generation.

User must be associated to rubric before LLM generation

Error message

User must be associated to rubric before LLM generation

What it means

validate_rubric_and_association_object asserts @rubric.user is present before allowing LLM generation: the rubric must be owned by (associated to) a user. Rubrics owned by an account or otherwise lacking a user owner cannot use LLM criteria generation.

Solutions

Ensure the rubric is created in a user context so user_id is set before enabling LLM generation.
Hide/disable the LLM generate UI for account-owned rubrics.
Pre-check rubric.user in the controller and return a clear error instead of letting the service raise a bare string.
If an existing rubric lacks an owner, re-create it under the current user rather than mutating ownership directly.

Example fix

// before
RubricLlmService.new(rubric).generate_criteria_via_llm(...)
// after
if rubric.user.nil?
  return render json: { error: 'rubric must be owned by a user for AI generation' }, status: :unprocessable_entity
end
RubricLlmService.new(rubric).generate_criteria_via_llm(...)

Defensive patterns

Strategy: validation

Validate before calling

return head :unprocessable_entity if rubric.user.nil?

Type guard

def user_owned_rubric?(rubric)
  rubric.respond_to?(:user) && rubric.user.present?
end

Try / catch

begin
  service.generate_criteria_via_llm(...)
rescue RuntimeError => e
  raise unless e.message == 'User must be associated to rubric before LLM generation'
  render json: { error: 'rubric has no owning user' }, status: :unprocessable_entity
end

Prevention

Create rubrics in user context so user_id is always populated when AI features are used.
Hide AI generation UI for account-owned rubrics.
Assert rubric.user in specs covering the LLM flow.

When it happens

Trigger: Calling generate_criteria_via_llm or regenerate_criteria_via_llm on a rubric whose user_id is nil — e.g. an account-level rubric, a rubric created without user_context, or a rubric where ownership was never set.

Common situations: Admin/account rubrics opened in an editor that exposes the LLM button; rubrics imported/migrated without an owner; specs or scripts constructing Rubric.new without user assignment.

Related errors

AI-assisted analysis of instructure/canvas-lms@1c9f0bb801 (2026-09-15). Data as JSON: /api/errors/42a9cf34c737c07c. Report an issue: GitHub.

Appendix: source

Thrown at app/services/rubric_llm_service.rb:193

  def resolve_generate_options(generate_options)
    DEFAULT_GENERATE_OPTIONS.merge(generate_options.symbolize_keys)
  end

  def resolve_regenerate_options(generate_options, regenerate_options)
    resolved = resolve_generate_options(generate_options)
    resolved.merge(
      additional_user_prompt: regenerate_options.symbolize_keys[:additional_user_prompt].presence ||
                              resolved[:additional_prompt_info].presence ||
                              "No specific expectations, just improve it."
    )
  end

  def validate_rubric_and_association_object(association_object)
    unless association_object.is_a?(AbstractAssignment)
      raise "LLM generation is only available for rubrics associated with an Assignment"
    end
    raise "User must be associated to rubric before LLM generation" unless @rubric.user
  end

  def call_llm_with_prefill(llm_config, prompt, root_account_uuid)
    response = nil
    time = Benchmark.measure do
      response = CedarClient.conversation(
        messages:
         [{ role: "User", text: prompt },
          { role: "Assistant", text: "{" }],
        model: llm_config.model_id,
        feature_slug: GENERATE_FEATURE_SLUG,
        root_account_uuid:,
        current_user: @rubric.user
      ).response
    end
    [response, time]
  end

View on GitHub (pinned to 1c9f0bb801)