Vespa is an open-source AI search engine, big-data serving engine, and vector database originally developed inside Yahoo and spun out as Vespa.ai AS. Vespa combines vector search, text search (BM25), structured filtering, and machine-learned ranking — including native tensor inference — into a single distributed serving engine that scales to billions of documents with sub-100ms latency. Vespa Cloud is the fully managed commercial offering operated by the Vespa.ai team across AWS and GCP, with Startup, Basic, Commercial, and Enterprise plans plus a Self-Managed option for customers running the open-source engine on their own infrastructure. Vespa is widely used at Spotify, Perplexity, Yahoo, Farfetch, and Elicit for search, recommendation, personalization, and Retrieval-Augmented Generation (RAG).
Vespa publishes 9 APIs on the APIs.io network, including Query API, Documents API, Visit API, and 6 more. Tagged areas include Artificial Intelligence, Search, Vector Database, Big Data, and Machine Learning.
The Vespa catalog on APIs.io includes 1 JSON-LD context and 2 Spectral governance rulesets.
Vespa’s developer surface includes authentication, documentation, getting-started guide, engineering blog, pricing, developer console, support, and 35 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
Horizontal (data, software, accessibility, platform) regime, so
Regulatory Posture carries 15 points of the composite.
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provider repo — the
applicability map is public and we will correct it.
Open Source Surface applies to this provider. This product is open source and we
read its repository directly, so Open Source Surface carries
10 points of the composite. It is scored from what the repository actually
publishes — a security policy, a contribution guide, a release history, a code of conduct — read live from the
provider rather than inferred from our own catalog pointers.
This facet adds; nothing was taken away to make room for it. An open-source project is not excused from
the commercial facets, because exemption would strip it of the points it does earn.
If we have the wrong repository, or this product is not open source, say so on your
provider repo and we
will drop the facet rather than have you publish against it.
Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it
carries 10 points of the composite. It is scored from the published contracts
themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already
holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in
front of it, and the first time that check is skipped a duplicate record is created.
Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet,
not penalised by it.
The six quality facets above are damped to 65 points between them,
because both conditional facets apply and carry
35 points together. That is why each facet's contribution is shown against a damped
maximum: raising a quality facet moves the composite by 65% of its nominal
weight, not 100%. The full arithmetic is at apis.io/rating/.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/vespa-ai: open an issue to ask a question, or submit a pull request to add artifacts.
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The Vespa Deploy API (/application/v2) manages application packages on a Vespa configuration server. It supports preparing, activating, and tearing down application packages, se...
The Vespa Tenant API (/application/v2/tenant) manages tenants and applications hosted on a Vespa configuration server or Vespa Cloud control plane. It exposes operations for cre...
The Vespa Config API (/config/v2) lets services in a Vespa application retrieve their configuration from a Vespa configuration server using the config-server / config-proxy prot...
The Vespa Cluster Controller API (/cluster/v2) exposes runtime state and management endpoints for a Vespa content cluster — including node state queries, maintenance-mode transi...
The Vespa State API (/state/v1) exposes per-service health, version, and metrics endpoints for any Vespa node — used by orchestration tooling, monitoring agents, and load balanc...
Vespa exposes a family of metrics endpoints (/metrics/v1, /metrics/v2, /prometheus/v1) that publish Vespa engine and application metrics in JSON or Prometheus exposition format ...
Combine BM25 text relevance with vector similarity and structured filters in a single query executed by Vespa's multi-phase ranking pipeline.
Retrieval Augmented Generation
Serve grounded context to large language models by indexing documents, chunks, and embeddings in Vespa and retrieving them with hybrid search at sub-100ms latency.
Recommendation and Personalization
Power recommendation systems with machine-learned ranking, real-time feature updates, and tensor inference over user and item embeddings.
Ad Targeting and Real-Time Bidding
Match candidate ads against user context and serve ranked impressions within tight latency budgets using Vespa's distributed serving engine.
E-Commerce Search and Browse
Combine faceted navigation, structured filters, text relevance, and learned ranking for large product catalogs with frequent updates.
Streaming Search for Personal Data
Run "streaming search" mode that scans a user's personal corpus on demand — ideal for mail, messaging, and document search where each user has their own private index.
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