[bot] RubyLLM content moderation (`RubyLLM.moderate`) not instrumented

[braintrust-bot]

Summary

The ruby_llm gem provides RubyLLM.moderate(input, ...) for AI-powered content moderation. This API is not instrumented by this SDK. The current RubyLLM integration only instruments RubyLLM::Chat. Content moderation uses an AI classification model to screen text and images for harmful content, and is a distinct execution surface from chat completions.

This is a cross-library parity gap: the Braintrust Ruby SDK already instruments OpenAI's moderation API for both the openai gem (OpenAI::Resources::Moderations) and the ruby-openai gem (ModerationsPatcher). The equivalent ruby_llm surface has no instrumentation.

What is missing

RubyLLM.moderate(input, model:, with:, provider:, ...) / RubyLLM::Moderation.moderate(input, ...) — invokes a provider moderation model (e.g., OpenAI's omni-moderation-latest) and returns a RubyLLM::Moderation object containing:

• id — provider-assigned identifier
• model — model ID used for moderation
• results — array of Result objects with category flags and scores

What a span should capture

• Input: text string(s) and/or image attachments being moderated
• Metadata: model, provider, endpoint
• Output: flagged status (flagged?), flagged categories, per-category scores
• Metrics: time_to_first_token (latency)

The implementation pattern is established: ModerationsPatcher for openai and ruby-openai gems both wrap a single create-style method. A new ModerationPatcher for ruby_llm would wrap Moderation.moderate.

Braintrust docs status

not_found — The Braintrust RubyLLM integration docs at https://www.braintrust.dev/docs/integrations/sdk-integrations/ruby-llm document only chat completions, tool calls, token usage, and streaming. Moderation is not mentioned. The OpenAI integration page does describe moderation support for the openai gem.

Upstream sources

• RubyLLM Moderation class: https://github.com/crmne/ruby_llm/blob/main/lib/ruby_llm/moderation.rb
• RubyLLM module moderate method: https://github.com/crmne/ruby_llm/blob/main/lib/ruby_llm.rb

Local repo files inspected

• lib/braintrust/contrib/ruby_llm/patcher.rb — defines only ChatPatcher; no ModerationPatcher
• lib/braintrust/contrib/ruby_llm/integration.rb — registers [ChatPatcher] only
• lib/braintrust/contrib/openai/instrumentation/moderations.rb — existing OpenAI moderation instrumentation (pattern to follow)
• lib/braintrust/contrib/openai/patcher.rb — ModerationsPatcher demonstrates the patcher pattern
• lib/braintrust/contrib/ruby_openai/instrumentation/moderations.rb — ruby-openai moderation instrumentation
• Grep for moderate, Moderation, ModerationPatcher across lib/braintrust/contrib/ruby_llm/ returns zero matches