Promotion Decision: provider-agnostic-llm-facade

Decision

Status: accepted Date: 2026-09-26

Rationale

Foundational architectural pattern decoupling autonomous orchestration workflows from vendor-specific model APIs, implemented robustly in LiteLLMClient with symmetrical offline test doubles.

Evidence Summary

• Recurring Implementation Across Flowrunner And Agenticmerger Modules
• Current Architecture State Ast Support In Src/Cas Runner/Llm/Litellm Client.Py
• Cross-Project Applicability For Llm-Driven Orchestration Runtimes
• Governance Model Alignment With Deterministic Ci Test Double Capabilities

Governance Assessment

Criteria Met

• [x] Significance
• [x] Reusability
• [x] Recurrence
• [x] Evidence Quality
• [x] Governance Maturity
• [x] Strategic Alignment

Governance Risks

• Vendor abstraction leakage if vendor-specific parameters or error structures are not normalized

Traceability

• Pattern Proposal: provider-agnostic-llm-facade
• Promotion Recommendation: recommendation-provider-agnostic-llm-facade

Next Step: Adr Generation