---
title: "Compute Index Weights"
method: POST
path: "/v1/tools/compute_index_weights"
tags: ["TODO_TAGS_REVIEW"]
---

# Compute Index Weights

`POST /v1/tools/compute_index_weights`

## Request

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

Computes (or receipts an externally-declared) weight per constituent from a stated methodology (market-cap, float-adjusted-market-cap, equal-weight, price-weight, or factor-tilted) and caller-supplied inputs, giving the weight set its own citable execution_hash separate from the constituent-membership fact in art-557. HARD FENCE: every input row (market_cap/price/float_factor/factor_score) is supplied and asserted, never fetched (zero-egress); this attests THAT a weight set was computed exactly as stated from the declared inputs, never whether those inputs are accurate. weight_sum_check is a hard local check (sum of weights within 1e-9 of 1.0), not a re-fetch. constituents_ref is optional and backward-compatible: a caller with no art-557 artifact yet still gets a valid weighting receipt over its declared constituent list. Second entry of the Financial Index/Benchmark Administrator Lineage family. Not fund NAV recomputation (art-373) or any benchmark-publisher scorecard. EU Benchmark Regulation (BMR, Regulation (EU) 2016/1011) Art 12(1) and SEBI (Index Providers) Regulations, 2024 Reg 18(1)/18(3) citations informative only.

**Tool URL:** https://ainumbers.co/chaingraph/art-645-compute-index-weights.html

## Request body

- object
  - `as_of_date` unknown
  - `constituents_ref` unknown, required
  - `index_id` unknown
  - `inputs` unknown[], required
    - unknown
  - `weighting_methodology` unknown

## Response `200`

Successful tool execution result

- object
  - `as_of_date` string
  - `constituents_ref` object
    - `execution_hash` string
    - `tool_id` string
  - `fence` string
  - `index_id` string
  - `methodology_notes` string
  - `not_proven` object[]
    - `detail` string
    - `item` string
  - `regulatory_framework` string
  - `structural_error` string
  - `weight_sum_check` integer
  - `weight_sum_within_tolerance` boolean
  - `weighting_methodology` string
  - `weights` object[]
    - `security_id` string
    - `weight` 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)