SpreadBench NCSX-IS — AI Infrastructure Bond Issuance Spread Index

com.spreadbenchPublished by spreadbench.comOfficial publisherv0.3.0Updated Nov 6, 2026

AI-infrastructure bond issuance-spread index (NCSX-IS): 13 bonds, 2 tiers, 14 free MCP tools.

VerifiedStreamable HTTPWeb executableFinanceData & Analytics

Overview

AI-generated overview

Read-only MCP server for SpreadBench NCSX-IS, an issuance-spread index of 13 AI-infrastructure (Neocloud) bonds, with 14 keyless tools for levels…

What you can do
  • Read the index level, secured and unsecured sub-indices, and the full index definition
  • List and filter the 13 constituent bonds by issuer, ticker or note keyword, with coupons, maturities and spreads
  • Inspect the Treasury par-yield curve used, US high-yield and investment-grade OAS reference series, and the maturity wall by year
  • Review SEC filing radar for 9 AI-infrastructure issuers and quarterly N-PORT fair-value marks converted to spread
  • Replay the 13 pricing events behind the current level, with per-bond pull attribution
  • Run reverse pricing for a hypothetical coupon and tenor, including rank, peer set and the resulting index level
When to use it
Useful when an assistant needs to answer questions about AI-infrastructure or Neocloud bond issuance spreads, compare them with broader credit indices, check SEC filings and fund marks, or estimate where a new bond would price. It is a point-in-time, event-driven benchmark, not a daily series or a traded CDS level.
Requirements
Remote streamable-HTTP endpoint at spreadbench.com, or a local stdio install via npm (global install of the package, then the ncsx-mcp command). No API key, signup or account is required, and no environment variables or headers are declared. Network access to spreadbench.com is needed.
Before you install
Read-only tools with no write or destructive hints, and no credentials requested. The main risk is misquoting: every payload carries a data_status field, and values marked retired_seed or seed are withdrawn demo numbers that must never be presented as market levels. Some legacy tool names return retirement notices. The provider states it issues no credit ratings or investment advice, so output should not be treated as such.

Installation

In SourceWeft

  1. Open SpreadBench NCSX-IS — AI Infrastructure Bond Issuance Spread Index in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/com.spreadbench%2Fncsx/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "spreadbench-ncsx-is-ai-infrastructure-bo": {
      "type": "http",
      "url": "https://spreadbench.com/mcp"
    }
  }
}

README

SpreadBench NCSX-IS — MCP server

Official Model Context Protocol server for SpreadBench NCSX-IS, an issuance-spread benchmark for AI-infrastructure (Neocloud) bonds.

What NCSX-IS measures. For each constituent bond, the coupon minus the US Treasury yield of matching tenor on that bond's pricing date, weighted by face value. It is a point-in-time issuance spread — event-driven, no daily frequency, and not a traded CDS level or a rating. SpreadBench publishes no credit ratings and no investment advice.

Live data: https://spreadbench.com · Methodology + DOI: https://spreadbench.com/methodology.html · JSON API: https://spreadbench.com/api.html


Two ways to connect

1. Remote (streamable-http, nothing to install)

json
{  "mcpServers": {    "ncsx": {      "type": "streamable-http",      "url": "https://spreadbench.com/mcp"    }  }}

Free, no API key, no signup.

2. Local (stdio, same tool set)

bash
npm install -g github:BrianTian818/spreadbench-ncsx-mcp# or, without npm registry:npm install -g https://spreadbench.com/download/ncsx-mcp-0.3.0.tgz
json
{  "mcpServers": {    "ncsx": { "command": "ncsx-mcp" }  }}

Both transports share one tool definition file (tools.js), so they never drift apart.


Tools

Fourteen read-only tools, all keyless. Every tool declares readOnlyHint: true / destructiveHint: false, so clients do not prompt for write permission.

ToolReturns
ncsx_latestStart here for "what is the level". Latest NCSX-IS reading, secured / unsecured sub-indices, constituent and issuer counts, notional, as-of date, methodology version, DOI, data_status
ncsx_indexStructural, not a single number. Full index definition, sub-index notionals, coverage notes
ncsx_constituentsThe whole universe, no filter. All 13 constituent bonds: issuer, ticker, coupon, maturity, size, seniority, pricing date, matched Treasury, issuance spread in bp
ncsx_bondFiltered lookup for one issuer — matches issuer / ticker / note keyword and returns only matching bonds
ncsx_curveThe Treasury par-yield curve used on the pricing date (14 tenors, linear interpolation, no extrapolation) plus recent history
ncsx_sectorUS high-yield / investment-grade OAS reference series for comparison
ncsx_filingsSEC filing radar for 9 AI-infrastructure issuers, last 45 days, noise forms filtered; pricing-chain forms (FWP / 424B* / S-3*) flagged pricing_signal
ncsx_marksSecond, independent layer: quarterly fair-value marks from SEC Form N-PORT filings, converted to spread
ncsx_wallMaturity wall by year with secured / unsecured split; pass year to drill into one cohort
ncsx_storiesCitable data stories recomputed live, each with headline numbers, bilingual page and a 1200x630 share card
ncsx_facts16 quotable numbers, each with value, unit, as_of, a human-readable calc and a source; filter by id or q
ncsx_eventsHistory as an event replay. 13 pricing events in order, level after each, change in bp and per-bond pull attribution (pull_bp), so pulls sum to the event delta; filter by since or ticker
ncsx_rulerReverse pricing. Given a coupon and a tenor: interpolated Treasury (never extrapolated), issuance spread, rank among the 13, gap to the index level and to the same-structure tier, and the index level after adding the bond at a given size. Pass issuer to get that issuer's own bonds already in the index as a pricing history. Recomputed on every call — nothing is stored. Also returns a like-for-like comparable set (peer_set: median / notional-weighted / range / rank inside the set; peer_window_years defaults to ±1y, and when the window is empty it falls back to the nearest tenor band with the distance stated).
ncsx_methodologyMethodology version, DOI, license, data sources and their licensing status, full formula chain

Three names from the demo-era server — ncsx_levels, ncsx_attribution, ncsx_weekly — are not listed any more, but still answer if an old client calls them: they return a structured retirement notice rather than an error.


Read data_status before you quote anything

Every payload carries a data_status field. This is the single most important field in the schema:

data_statusMeaning
real_issuanceObserved public issuance data. Safe to quote; reproducible from SEC filings.
retired_seed / seedA withdrawn demo series. Numbers were generated for layout testing. Never quote as market levels.

If a tool returns status: "retired", the endpoint was withdrawn — read the replacement field and move on. Nothing in this server will silently hand you demo numbers.


Example prompts

  • "What is the current NCSX-IS spread, and how does the unsecured cohort differ from the secured one?"
  • "Which CoreWeave bonds are in the index and what spread did each price at?"
  • "Compare NCSX-IS against the US high-yield OAS over the last 90 days."
  • "Which Treasury tenors does the index lean on most?"
  • "Is the NCSX-IS level consistent with the latest SEC N-PORT marks?"
  • "A $1.5bn 5-year note at 8.25% — where does that price relative to this market, and what would it do to NCSX-IS?"
  • "How did NCSX-IS get from 517.7bp to 432.3bp, and which issuer pulled it the most?"

Conventions

  • Identifier: constituents are identified by issuer + coupon + maturity. They do not carry CUSIPs — do not query by CUSIP.
  • Units: spreads in basis points over the Treasury at pricing. Notionals in USD millions.
  • Frequency: event-driven. There is no T+1 update and no daily change field.
  • Reproducibility: every number is derived from public filings (SEC EDGAR) and the US Treasury par-yield curve. The methodology page states the exact formula and the interpolation rule.

Notes on naming

Older versions of this server exposed Composite / HY / IG tiers and 90-day daily series. Those came from a demo dataset and were withdrawn on 2026-11-04 in favour of the issuance-spread methodology (v0.2.0-real). The three retired names listed above remain callable only so that old clients receive an explicit notice instead of an error; they are hidden from tools/list.

Directory listings

This server is listed in the official MCP Registry as com.spreadbench/ncsx, and is indexed by Glama (A tier) and brick.blue. glama.json in this repo claims the listing for its maintainer.

License

MIT. Data is published for research and citation; SpreadBench does not provide credit ratings or investment advice.

Source: README.md at commit 200df58

Tools

14

ncsx_latest

ncsx latest

The one number to quote — use this first for "what is NCSX-IS / what is the spread right now". Returns a compact record: headline issuance spread (coupon minus the Treasury yield of matching tenor on the pricing date, weighted by face value), the secured and unsecured sub-indices, constituent/issuer counts, notional, as-of date, methodology version, DOI and data_status. This is a point-in-time issuance spread, not a traded level: there is no daily change. Read data_status before quoting — "real_issuance" means observed public issuance data; anything marked "retired_seed" or "seed" is a demo series and must not be quoted.

Takes no parameters.

ncsx_index

ncsx index

The full index definition, not a single number — use when the question is structural ("how is NCSX-IS built", "show all tiers") rather than "what is the level". Returns the NCSX-IS / secured / unsecured tiers side by side with each tier's notional and constituent count, plus index-level coverage notes and data_status. For a quick headline reading use ncsx_latest instead.

Takes no parameters.

ncsx_constituents

ncsx constituents

The whole universe in one response — all 13 constituent bonds, no filter: issuer, ticker, coupon, maturity, size, seniority, pricing date, tenor, the matched Treasury yield on that date, and the resulting issuance spread in bp. Use it to list the index or to compute weights; if the user named one issuer, use ncsx_bond instead so you do not pull 13 rows to answer about one.

Takes no parameters.

ncsx_bond

ncsx bond

Filtered lookup for one issuer, ticker or note keyword (e.g. "CoreWeave", "GLXY", "Helios", "2031") — returns only the matching constituent bonds, not the whole universe. Constituents are identified by issuer + coupon + maturity; they do NOT carry CUSIPs, so never query by CUSIP. Use ncsx_constituents when you need every bond.

Parametersqrequired

ncsx_curve

ncsx curve

The US Treasury par-yield curve used on the pricing date (14 tenors, interpolated linearly, never extrapolated) plus its recent history. Every constituent spread is measured against this curve.

Takes no parameters.

ncsx_sector

ncsx sector

Context series for the AI-infrastructure credit complex: US high-yield OAS, US investment-grade OAS and related ICE BofA indices, with 30-day change and daily history — use these to compare NCSX-IS against the broader market.

Takes no parameters.

ncsx_filings

ncsx filings

SEC filing radar for the 9 AI-infrastructure issuers covered by SpreadBench (6 in NCSX-IS plus Nebius, IREN and Hut 8 on the watchlist): every filing from the last 45 days, noise forms (ownership, routine) filtered out, pricing-chain forms (FWP, 424B*, S-3*, F-10) flagged with pricing_signal=true, each row linked to the EDGAR original. NCSX-IS is event-driven, so a new pricing-chain filing is what triggers an index re-version — use this to check whether a re-version is coming.

Parametersformissuer

ncsx_marks

ncsx marks

Second, independent layer: quarterly fair-value marks for AI-infrastructure bonds as reported by US registered funds on SEC Form N-PORT (Level 2), converted to spread over the matched Treasury. Compare with NCSX-IS to see issuance spread vs. mark spread.

Takes no parameters.

ncsx_wall

ncsx wall

Maturity wall for AI-infrastructure bonds: outstanding face value by maturity year, split secured / unsecured, with the full bond list per year. As of 2026-11-04, $17.86B (63.6% of the index) matures in 2031, and 7 of those 8 bonds priced within 2026 — a single issuance window produced a same-maturity wall. Pass year (e.g. 2030) to get just that year: its face value, share of the index, secured/unsecured split and every bond maturing in it. Use for refinancing-concentration and supply-schedule questions. Terms and maturity dates are facts from SEC filings; this is not a refinancing forecast or credit judgement.

Parametersyear

ncsx_stories

ncsx stories

Citable data stories (editorial layer) recomputed live from the same public data as the index, each with headline numbers, bilingual page URLs and a ready-to-post 1200x630 share card: (1) the maturity wall of the peak year; (2) the CoreWeave repricing — every CoreWeave bond widened 191-258bp between issuance and the latest N-PORT fund marks (2026-08-31) while same-sector peers (GLXY / CORZ / CIFR) moved only 17.6-40.7bp. Returns numbers computed from current universe + marks data, not cached text. Facts only — no ratings, no investment advice.

Takes no parameters.

ncsx_facts

ncsx facts

The quotable-facts layer: 16 pre-computed, individually sourced numbers covering the whole index — index and sub-index levels, the secured-vs-unsecured structure premium, universe size, per-bond spread range, peak maturity year and its share, the 2030 window, N-PORT marks coverage and implied delta, the CoreWeave repricing, peer repricing, and NCSX vs US HY OAS with rating-bucket reads. Every fact carries value, unit, as_of, a human-readable calc (so you can restate how it was derived) and a source URL. Use this when the user wants a number to cite, a comparison, or several figures at once — instead of stitching five endpoints together. Filter with id (exact, comma-separated) or q (substring on the label). Pass nothing to get all 16.

Parametersqid

ncsx_events

ncsx events

The index history — use this when the question is "how did NCSX-IS get to its current level" rather than "what is the level". NCSX-IS is event-driven: it only moves when a new bond prices, so the history is a replay of 13 pricing events from 2025-05-19 to 2026-07-24. Each event returns the date, the index level after the event, the change in bp, notional added, and the per-bond pull attribution (pull_bp = that bond's post-add weight × its spread minus the pre-add index level, so pulls sum to the event delta). Headline: 517.7bp at inception, trough 410.0bp (2026-06-16), 432.3bp now, net -85.4bp over 431 days across 13 events (4 up / 8 down). Filter with since ("2026" or "2026-02-05") or ticker ("CRWV") to see only that window or that issuer's pricing events. There is no daily series and no traded level — do not describe these as closes or weekly moves.

Parameterssinceticker

ncsx_ruler

ncsx ruler

Reverse pricing — the question every other tool cannot answer: given a coupon and a tenor, where would a new AI-infrastructure bond land? Returns the matched Treasury yield (linear interpolation between the two adjacent curve tenors, never extrapolated), the resulting issuance spread in bp using the same formula as every constituent ((coupon - UST) x 100), how it compares with the index level and with the same-structure tier, its rank among the 13 constituents, a like-for-like comparable set (same structure, tenor within ±1y, with median / weighted / rank), and — if you pass a size — the index level after adding it (face-value weighted: the same arithmetic as the pull_bp attribution in ncsx_events). Pass issuer to also get that issuer's own bonds already in the index (coupon, tenor, spread at pricing, gap to the hypothetical new bond) — the first thing an underwriter checks is what the same name paid last time. Nothing is stored: it is recomputed on every call from the current curve, universe and index, so it can never go stale. Use it for "is 9.5% for 5 years tight or wide for this market", "what does an 8% coupon imply", "what happens to NCSX-IS if another $2bn prices at this spread", "how would a new CoreWeave bond compare with its existing stack". Facts and arithmetic only: it does not recommend a coupon and issues no rating or investment advice.

Parametersissuersize_mmsenioritycoupon_pctrequiredtenor_yearsrequiredpeer_window_years

ncsx_methodology

ncsx methodology

Methodology metadata and full formula chain: version, DOI, license, data sources and their licensing status, the exact spread and weighting formulas, and what is explicitly NOT measured.

Takes no parameters.

Version history

5
  1. v0.3.0LatestNov 6, 2026
  2. v0.2.9Nov 6, 2026
  3. v0.2.4Nov 5, 2026
  4. v0.2.2Nov 5, 2026
  5. v0.1.0Nov 4, 2026

Score

100% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts

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