/api/v1/public/indices/{id}GETIndex detail enriched with trailing-return/risk stats and constituent-derived composition analytics (state exposure, maturity, weight attribution, and per-constituent return attribution over 1d/7d/30d windows). Composition weights and constituent prices are computed together server-side (weights renormalized over the constituents that actually entered the price, prices being the mids that entered that same cycle; child levels of a composite anchor at the parent's resolved cycle), so attribution reconciles to the published price even for a partial composite basket and a post-compute trade does not move it; an index with no compute cycle yet falls back to its stored base weights and current prices.
Response
200 · Index detail
index_id *string
Stable identifier for the index (for example
red). Use it as the {id} path parameter on the index detail, constituents, and price endpoints.name *string
Full display name of the index.
ticker *string
Short uppercase symbol for the index (for example
RED). This endpoint accepts either this ticker (case-insensitively) or index_id as its path parameter.description *stringnull
Free-text description of what the index tracks.
methodology?stringnull
Registered methodology key used to compute the index. Omitted only when no methodology is stored.
constituents_count *integer
Number of constituents in the index: member markets for a market-basket index, or child sub-indices for a composite. A derived index that inherits its book from a base index reports 0 and names that base in
base_index_id.is_composite *boolean
True for a composite index (its constituents are other indices and its price blends child sub-index values); false for a market-basket index (its constituents are exchange markets). Always present, so a client can branch on index kind even when the index has no constituents yet.
office_category *stringnull
The index's declared office category (lowercase, e.g. "senate"), the input to methodology weighting and composite child-weight derivation. Null for composites and uncategorized indices; always present.
base_index_id?stringnull
For a derived total_return index, the composite index it compounds the returns of; null for the curated families, which have no base. The detail page shows this in place of the constituent count a derived index lacks.
latest_price?numbernull
Most recent index level, on the base-100 index scale (100 is neutral). See
level_interpretation for how this index's methodology frames the level, since a probability family and a total-return family read the same number differently.level_interpretation?object[]
Methodology-resolved rows explaining what latest_price means, formatted server-side (the curated families frame it as a composite probability, total_return as a compounding return). The client renders them verbatim; omitted when the level or the methodology is unavailable.
Show item properties
label *string
value *string
price_change_1d?numbernull
Absolute change in index points (not a percent) from the previous daily close to
latest_price. The baseline is the last completed daily close before the current day in US Eastern time, so this is a change against a settled value rather than a rolling 24-hour window.price_change_7d?numbernull
Absolute change in index points (not a percent) from the daily close seven days before the current day in US Eastern time to
latest_price. Null when the index has no daily close that far back.previous_close_1d?numbernull
The index level at the previous daily close, meaning the last completed daily close before the current day in US Eastern time, not a rolling 24-hour window. Returned by
GET /api/v1/public/indices/{id}; omitted on GET /api/v1/indices/{id}.previous_close_7d?numbernull
The index level at the daily close seven days before the current day in US Eastern time, the baseline
price_change_7d is measured against. Returned by GET /api/v1/public/indices/{id}; omitted on GET /api/v1/indices/{id}.stats?object | null
Trailing returns and risk statistics computed from the index's daily close series over roughly the trailing 400 days. Returned by both index detail endpoints; the values are null individually when the series is too short for that window.
composition?object | null
Breakdown of the index over its flattened constituents: per-state exposure and a maturity profile of when those constituents expire.
halted?boolean
True when the latest index value was carried forward because the index fell below its constituent floor.
halt_valid_constituents?integernull
When halted, the valid (priced, guardrail-passing) constituents at the most recent halt cycle. Omitted when not halted.
halt_min_constituents?integernull
When halted, the category constituent floor the index fell below. Omitted when not halted.
halt_reason?stringnull
When halted, a render-ready human-readable explanation of the halt, composed from the counts above. Omitted when not halted.
404 · Index not found
error?string
Stable, machine-readable code identifying the failure; branch on this rather than on
message. One of bad_request, unauthorized, forbidden, not_found, conflict, service_unavailable, upstream_error, service_error, or internal_error.message?string
Human-readable explanation, safe to show to a user. For client errors it names the specific problem; for server-side failures it is a generic notice and the underlying detail is deliberately withheld.
Request example
curl -X GET "https://api.adjacent.markets/api/v1/public/indices/<id>"
Response example
{ "index_id": "red", "name": "Republican Political Future Index", "ticker": "RED", "description": "Composite of Republican party-line contests across all levels of office in the United States", "office_category": null, "methodology": "upfi", "is_composite": true, "constituents_count": 5, "latest_price": 96.6691, "level_interpretation": [ { "label": "Index level", "value": "96.7" }, { "label": "Composite probability value", "value": "46.7%" }, { "label": "Interpretation", "value": "-3.3 pts" } ], "price_change_1d": -0.0124, "price_change_7d": 0.9173, "previous_close_1d": 96.6815, "previous_close_7d": 95.7518, "stats": { "trailing_returns": [ { "label": "1D", "value": -0.01282561813790593 }, { "label": "1W", "value": 0.9579976564409206 } ] } }