Framework-Fit Decision Tree at Project Kickoff · SOP (ENHANCE overlay)

Overlay posture: this is the capstone Phase-D skill — the most-cited entry at any project kickoff. It decides which layer(s) you need and which framework owns each layer. It does not teach any framework's API; for that, descend to the per-framework SOPs (langgraph-sop, llamaindex-sop, dspy-sop, crewai-sop, vllm-sop, aider-sop, dify-sop). Every load-bearing claim carries an inline source tag resolving in references/R1-decision-tree.md.

Neutrality note: vendor pages each claim the center of the universe (LangChain: "use LangGraph for production"; LlamaIndex: "the document agent platform"; Dify: "scaffolding is the bottleneck"). This skill quotes those claims but does not adopt any of them. The 7 SOPs disagree on the crossover points; we surface the disagreements rather than papering over them.

1. 何时激活 (When to Activate)