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MCP server · Code & DevOps

SpreadBench NCSX-IS — AI Infrastructure Bond Issuance Spread Index

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

Checks passed
14 / 22

1 failed · 7 not measured

Median response
1212 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
14

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
410
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 1253 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-03-26, serverInfo.name ncsx.

  • Pass
    Lists tools

    tools/list returned 14 tools.

  • Fail
    Current protocol

    Negotiated 2025-03-26. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 1212 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 1249 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    14 of 14 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-06T06:22:30.270328Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using SpreadBench NCSX-IS — AI Infrastructure Bond Issuance Spread Index

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http spreadbench-ncsx-is-ai-infrastructure-bond-issuance-spread-index https://spreadbench.com/mcp

Capabilities

Tools 14

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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected1253 ms14
Connected1170 ms14