# Helious Treasury auctions API

**Canonical:** https://apis.io/apis/helious-io/helious-io-treasury-auctions-api/  
**Provider:** Helious — https://apis.io/providers/helious-io/  
**Base URL:** https://api.helious.io  
**Documentation:** https://helious.io/developers/

Helious Treasury auctions API is one of 12 APIs that [Helious](https://apis.io/providers/helious-io/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. This API exposes 2 JSON Schema definitions. Tagged areas include Treasury auctions. The published artifact set on APIs.io includes an OpenAPI specification and 2 JSON Schemas.

Auction results by tenor, with the tail against the when-issued yield.

## Operations (6)

| Method | Path | Summary |
|---|---|---|
| GET | `/v1/auctions` | Treasury auction results with the tail, in context |
| GET | `/api/seo/tenor-index` | All tracked Treasury auction tenors |
| GET | `/api/seo/tenor/{slug}` | Auction history for one tenor |
| GET | `/api/seo/csv/tenor/{slug}` | CSV sample: recent auctions for one tenor |
| GET | `/api/seo/auction-tails` | Treasury auction tails sample (JSON) |
| GET | `/api/seo/auction-tails.csv` | Treasury auction tails sample (CSV) |

## Machine-readable artifacts (3)

- **OpenAPI** — https://artifacts.apis.io/helious-io/openapi/helious-io-treasury-auctions-api-openapi.yml
- **JSONSchema** — https://artifacts.apis.io/helious-io/json-schema/helious-io-feed-item-schema.json
- **JSONSchema** — https://artifacts.apis.io/helious-io/json-schema/helious-io-envelope-schema.json

## Other Helious APIs (11)

- [Helious Agent sign-in and A2A API](https://apis.io/apis/helious-io/helious-io-agent-sign-in-and-a2a-api/)
- [Helious Ask Helious API](https://apis.io/apis/helious-io/helious-io-ask-helious-api/)
- [Helious Boards API](https://apis.io/apis/helious-io/helious-io-boards-api/)
- [Helious Economic data API](https://apis.io/apis/helious-io/helious-io-economic-data-api/)
- [Helious News and feed API](https://apis.io/apis/helious-io/helious-io-news-and-feed-api/)
- [Helious Rates and curve API](https://apis.io/apis/helious-io/helious-io-rates-and-curve-api/)
- [Helious Reference API](https://apis.io/apis/helious-io/helious-io-reference-api/)
- [Helious Series API](https://apis.io/apis/helious-io/helious-io-series-api/)
- [Helious The Fed API](https://apis.io/apis/helious-io/helious-io-the-fed-api/)
- [Helious The squawk API](https://apis.io/apis/helious-io/helious-io-the-squawk-api/)
- [Helious Your key API](https://apis.io/apis/helious-io/helious-io-your-key-api/)

## Tags

Treasury auctions

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/helious-io/helious-io-treasury-auctions-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/helious-io/.