The Agentic Bank

Underwriting Agent

⬡ Plumb Derives the underwriting decision; a chief-credit agent gates it.
◆ Supervised Specialist

Runs the loan through automated underwriting, checks the file against agency guidelines and investor overlays, builds the conditions and exceptions, and derives a cited decision. Every approve / deny passes to an independent chief-credit agent that re-derives it before the file commits.

Memory

Working The file, the AUS findings, and the conditions list being built.
Episodic Prior conditions cleared on this borrower's file.
Semantic Agency (Fannie/Freddie/FHA) guidelines, investor overlays, ECOA rules.
Procedural Condition-clearing playbooks per loan program.
Store Guideline corpus (RAG) + case store

Orchestration

pipeline MCPA2A

Harness · Managed Agents … case session with a guideline-retrieval toolset.

Tools

{ } Automated underwriting system (AUS) API Agency guidelines + overlays (RAG) Retrieval Document file (from intake) A2A Chief-credit agent approval A2A

Evals & guardrails

  • Fair-lending guardrail: outcomes monitored for disparate impact across segments.
  • Final approve / deny is NEVER auto-committed … a chief-credit agent re-derives every decision.
  • Citation discipline: every condition links to the specific guideline.
  • Agent-as-judge review of guideline application vs. the file.

Frontier edge

  • Causal reasoning: counterfactual condition analysis ('which single condition, if cleared, flips this file to approvable?'), so the borrower is asked for the thing that matters, not a blanket list.
  • Self-improving fleet: newly-learned guideline-overlay interpretations are shared across the underwriting population between runs, so one agent's clearing pattern lifts them all.
  • Formal action-gating: the decision is signed and replayable but provably cannot self-commit, so the final approve / deny passes through an independent chief-credit agent that re-derives it, with the full reasoning chain attached.

A sample run

Trigger Reconciled file arrives from the document agent (A2A).
  1. 1Run the AUS; pull findings and required conditions.
  2. 2Check the file against agency guidelines + investor overlays.
  3. 3Derive the decision with conditions, each cited to a guideline.
Output An approve-with-conditions decision handed to the chief-credit agent to re-derive and gate; two conditions auto-cleared from the file, three left for the borrower.

In numbers

5,400
Files cleared to UW / day
58%
Conditions auto-cleared

Handoffs

Across ⇢ Risk → Credit Risk for portfolio-level oversight

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