0008. LangGraph as the agent runtime

Status

Accepted. Date: 2026-11-04.

Context

Karani and future products run agents that need checkpointing, tool use, budgets and human approval. Writing an agent runtime is not where NeoForge has an edge.

Decision

ai.agents uses LangGraph as the runtime. Hephaestus supplies the Postgres checkpointer, tool registry, budget ceilings, human-approval interrupts and tracing. The module is rebuilt from Karani, not copied from DataQRL’s LangGraph orchestration, which stays DataQRL’s.

Consequences

We get a maintained runtime and put our work into the wrapper that enforces budgets, approvals and tracing. We track LangGraph’s API changes. ai.agents is Tier 3 and enters as experimental on demand.