Three agents, one bank
Thick · LangGraph
Thin · LangGraph
Thin ·
Context
One
Harness
Three agents call one bank. The thick agent calls it directly; both thin agents go through the context layer.
Agents
Context layer
The bank
Thick · LangGraph
Graph and policy file in code
Calls the bank directly
Thin · LangGraph
One loop + workflow document
MCP client, any harness
Thin ·
Context
One
Harness
One loop + workflow document
Rule gates on every tool call
AOS · ontology
Policy, controls, approvers
as entities and edges
SDG · named queries
Versioned, parameterised
lookups over the credit DB
ATI · API tools
The bank’s REST API, with
argument rules
Credit database
limits, exposures,
ratings, notes
Limit system
pre-deal check,
add-on
Booking
trades, excess
requests
every call ledgered
MCP
native