---
title: "Claims Reserve Adequacy Checker — Chain Ladder + Bornhuetter-Ferguson"
method: POST
path: "/v1/tools/check_claims_reserve_adequacy"
tags: ["reserving", "chain-ladder", "bornhuetter-ferguson", "loss-triangle", "IBNR", "LDF", "loss-development-factor", "reserve-adequacy", "actuarial", "CAS", "Friedland-2010", "Zero-PII"]
---

# Claims Reserve Adequacy Checker — Chain Ladder + Bornhuetter-Ferguson

`POST /v1/tools/check_claims_reserve_adequacy`

## Request

- Base URL: `https://ainumbers.co`
- URL: `https://ainumbers.co/v1/tools/check_claims_reserve_adequacy`
- Auth: none declared

Run the Chain Ladder (development) and Bornhuetter-Ferguson reserving methods on a loss development triangle. Computes age-to-age factors, loss development factors to ultimate, chain-ladder and B-F ultimate losses, IBNR by accident year, a selected (blended) IBNR, and a reserve adequacy signal versus a booked reserve. Flags >15% method divergence and low-credibility triangles. Client-side. Works offline. Zero PII.

**Tool URL:** https://ainumbers.co/tools/462-claims-reserve-adequacy-checker.html
**AP2/Policy Mandate export:** yes

## Request body

- object
  - `triangle` array[], required
    - number[]
  - `ldfMethod` 'vw' | 'simple' | 'vw3' | 'vw5' | 'manual', required
  - `tailFactor` number
  - `excludeDiag` boolean
  - `elr` number
  - `clWeight` number
  - `earnedPremium` number[]
  - `bookedReserve` number
  - `priorReserve` number

## Response `200`

Successful tool execution result

- object
  - `selected_ibnr` number
  - `chain_ladder_ibnr` number
  - `bornhuetter_ferguson_ibnr` number
  - `booked_reserve` number
  - `redundancy_deficiency` number
  - `redundancy_deficiency_pct` number
  - `adequacy_signal` 'ADEQUATE' | 'DEFICIENT'
  - `method_divergence_pct` number
  - `selected_ldfs_to_ultimate` number[]

---

[API](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite.md) · [All operations](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/llms.txt) · [OpenAPI document](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/revisions/b462e4f5bb28?raw)