Omni is the plugin’s default orchestration layer. It runs the standalone gepa==0.1.4 PyPI reflective engine beside the plugin-native AutoResearch and Meta-Harness engines, picks the strongest Phase 1 candidate, and starts a fresh Phase 2 continuation. The plugin-native best_of_n engine is the independent comparison baseline for standalone runs.
omni is a preflight target and workflow mode, not a public PyPI engine= value.
Phases
All Phase 1 branches share the same seed, objective, evaluator, dataset, and selection valset. test_set is removed from every Phase 1 task and used only for final held-out scoring by the continuation or wrapper. Phase 2 starts a new external run_dir and output_dir rather than resuming a Phase 1 branch.
Launch
Budget partitioning
The total evaluation and token budgets are divided into three exploration slices and one continuation slice. Evaluation remainders go to the continuation.
- An explicit positive
max_evals and/or max_token_cost is required.
- When
max_evals is the only bound, at least four evaluations are needed so every phase receives a positive slice.
- Use a standalone engine when the budget cannot support four phases.
Continuation choices
The default continuation is gepa, which uses the PyPI reflective engine and the read-only Chat Completions proposer. Set continuation_engine="autoresearch" or continuation_engine="meta_harness" to use a plugin-native agent continuation.
Standalone run_optimization(..., engine=...) bypasses Omni and receives the full supplied budget.
Backend and model selection
agent_backend remains a compatibility label for codex, pi, or claude. OPENAI_MODEL is authoritative for every branch. There is no provider-specific model or CLI login resolution.
The wrapper also preserves codex_command, pi_command, codex_timeout_seconds, codex_input_cost_per_million, codex_output_cost_per_million, max_concurrency, gepa_parallel_proposals, and stop_at_score. Codex input and output rates are required together when a Codex token cap is configured.
Runtime prerequisites
Run the local preflight before a real Omni run:
Preflight verifies the published GEPA API, plugin-native runtime primitives, and the three OPENAI_* variables. sandbox=False is rejected at the wrapper boundary, and the Chat Completions model receives no local tools.
Keep every run_dir and output_dir absolute and outside the checkout. Native evaluation artifacts include per-evaluation JSON, eval_trace.jsonl, progress, and a serializable result.json. Last modified on September 7, 2026
