Changelog | Opik Documentation

Ask Ollie to Explain Trace Cells

Error, duration, and cost cells across the Traces, Spans, and Threads tables now have an “Explain” button (the Ollie owl icon) that streams a plain-language explanation of that specific value without leaving the table — no need to open the trace panel and dig through raw payloads to understand why a call errored, took as long as it did, or cost what it did.

Online Evaluation Runs Are Now Traced

LLM-as-a-judge scoring runs (on traces, spans, and threads) are now recorded as monitoring traces automatically, with a prepare_evaluation span and one span per scoring call, including token usage and cost. They’re hidden from the main Logs view by default, and each rule on the Online Evaluation page now has a Go to traces action that opens a scoped, filtered view of that rule’s evaluation activity — useful for confirming a rule is running, checking what it cost, or debugging why it errored. This is on by default for all workspaces.

Bug Fixes & Improvements

• Diagnostics now explains why a run failed — Previously, a Diagnostics run that crashed or never started (for example, from exhausted LLM credits) just spun until it timed out, with no indication of what went wrong. Failed runs now show a specific reason (out of credits, rate limited, provider error, or never started) with a “Try again” action, and the failure timeout was cut from 12 minutes to 5.
• Playground and online scoring: Sonnet 5 and Fable 5 no longer error out — These models were missing from the capability list, so the Playground kept showing temperature/Top P sliders and sending those parameters, which the models reject. The sliders are now hidden and the parameters are no longer sent, matching the behavior already in place for Opus 4.7/4.8.
• Azure-hosted OpenAI model prices now load correctly — Model prices for the azure/* model family (gpt-4o, gpt-5, codex-mini, and others) were silently failing to load because of a provider-mapping gap, causing cost to show as unavailable for these models.
• Experiment and Playground traces now show up in scoped “Go to logs” views — Traces created by experiment runs and Playground runs were sometimes missing from their respective “Go to logs” tables even though the traces existed, due to a visibility-filter mismatch. These views now correctly scope by the experiment or run itself.
• Playground: dataset and metric selection redesigned — The “Run experiment” dialog is replaced by inline dataset and metrics dropdowns in the Playground header, so you can change either independently without reopening a modal. Metrics can also be created and edited in place.
• Permission gating extended to more pages — Users with the Annotator workspace role no longer see Agent Playground, Online Evaluation, or Alerts in the sidebar. Prompt Library view/edit access is now governed by the same permission system, at both the UI and API level.
• opik import --to-workspace for cross-workspace imports — The opik import CLI command accepts a --to-workspace option to import exported data into a different workspace than the one it was exported from, without needing to restructure the export directory as a workaround.
• opik migrate dataset --exclude-experiments — This flag skips migrating a dataset’s experiments and optimizations, migrating only the dataset and its version history. Useful for large datasets where the experiment/optimization cascade isn’t needed.
• Fixed intermittent errors loading prompt and dataset versions under load — A query pattern that caused MySQL to materialize large temporary tables could fail outright under load. Prompt and dataset version lookups are now rewritten to avoid the issue.

Performance Improvements

• Faster trace ingestion — Removed a redundant ClickHouse lookup that ran on every trace ingestion just to check the trace’s last-updated timestamp, reducing ingestion latency and ClickHouse load.
• SDK: shared connection resources across Opik() clients — Code that creates multiple Opik() clients (for example, one per task or request) now shares the underlying connection pool and background threads across clients with matching configuration instead of creating a full new stack each time, reducing thread and connection overhead.
• Self-hosted: ClickHouse FINAL reads no longer over-read on skip-indexed tables — Disabled the new ClickHouse 25.x default for use_skip_indexes_if_final_exact_mode, which was causing skip-indexed queries to read far more data than necessary; Opik’s queries already prune by primary key and project ID, so the exact mode isn’t needed.