Storage
Nobody ratified S3 as the object-storage standard. It became one because vendor after vendor implemented Amazon's interface on their own hardware, and an application written against one now runs against dozens by changing an endpoint. This is also the profile with the weakest evidence behind its adoption numbers, and it says so rather than presenting a confident table.
| Cohort | reimplementation — independent servers built against a published interface |
|---|---|
| Status | Published — 116 operations graded, 46 adopters recorded, none testable |
| Repository | https://github.com/api-commons/storage |
| Profiles | 1 in this domain |
The S3 Interface
8 core operations — the CRUD primitives and nothing else. Multipart upload does not reach core, and the deprecated ListObjects outpolls ListObjectsV2 five to one.
| Identifier | s3-2006-03-01 |
|---|---|
| Originator | Amazon Web Services |
| Source of truth |
boto/botocore — botocore/data/s3/2006-03-01/service-2.json
Apache-2.0
Pinned at aeb03fc4ae530e0b3f47d588b6021581db870c8c
116 operations, 722 shapes, protocol rest-xml, API version 2006-03-01. The catalog's own S3 spec carried 15 paths against these 116, which is why this was generated fresh. |
| How it was measured | 58 providers claim S3 compatibility and 12 publish a spec declaring an S3 operation — the thinnest evidence base of the five standards here, and every share should be read as a signal rather than a census. There is no tested grade and that was tested rather than assumed: an S3 server validates the signature before it routes the operation, so MinIO's public endpoint answers AccessDenied to a supported and an unsupported subresource alike, and AWS returns 307 to everything. The vendor compatibility matrices that would have been the natural evidence render client-side or mark support in no parseable structure, so they are recorded as claims and nothing is synthesised from them. |
| Tier | What it covers |
|---|---|
| Core 8 operations |
ListBuckets and ListObjects at 83.3%, then DeleteBucket, DeleteObject and GetObject at 75%, CreateBucket at 66.7%, HeadObject and PutObject at 58.3%. ListObjects — the version AWS has recommended against for years — outpolls ListObjectsV2 by five to one. What an ecosystem implements and what its originator recommends are different things. |
| Extended 8 operations |
Multipart upload (41.7% for CreateMultipartUpload), HeadBucket, CopyObject and ListObjectsV2 at 16.7%. The threshold here is a count rather than a percentage: with a cohort of 12, one declaration is 8.3% and a single provider is not corroboration. |
| Vendor 100 operations |
Declared by at most one provider. Nearly all of the bucket configuration surface — ?acl, ?cors, ?lifecycle, ?versioning, ?replication, Storage Lens, Access Grants. |
46 implementations recorded · as of 2026-09-13
| Evidence | Count | Meaning |
|---|---|---|
declared | 12 | Publishes an OpenAPI declaring S3 operations. This is the whole measurement. |
vendor-matrix | 2 | MinIO and Cloudflare R2 publish compatibility tables, recorded here as their claim with a URL and a date. No per-operation support is read from them. |
prose | 32 | Says S3-compatible and nothing a reader can check. |
tested | 0 | Structurally unavailable. Authorization precedes routing, so an anonymous caller learns nothing about which operations exist. |
The full adopter registry · the adopter matrix — every entry carries the URL it was read from and the date it was read.
Artifacts
-
Model
— Model
The artifact of record — tier-stamped, with the query subresources that identify 99 of the 116 operations intact. -
OpenAPI
— OpenAPI
A labelled convenience. The API collapses to 12 method and path pairs, so each keeps one operation and lists the rest in x-s3-operations. -
Profile
— Profile
All 116 operations with tier, evidence and subresource. -
Spectral Ruleset
— SpectralRules
8 core-operation rules plus one that warns on JSON-only responses, because S3 is rest-xml. It matches path shape rather than parameter spelling. -
Arazzo
— Arazzo
Create, put, get, list, delete, delete. The only conformance flow in this programme that cannot be run anonymously. -
MCP Tools
— MCP
MCP tool definitions for the core tier.
Licensing
Derived from botocore's service-2.json under Apache-2.0, with its NOTICE carried in the repository. API Commons artifacts are CC BY-NC-SA 4.0 and code is Apache-2.0. Not published by, affiliated with, or endorsed by Amazon Web Services; the name S3 appears as a factual reference to the interface described.
Tags
Object StorageStorageCloud Storage
Further reading
- Why OpenAPI cannot describe S3 — 99 of 116 operations are identified by a query subresource and the API collapses to 12 method and path pairs. The profile records every collision.
- The adopters building block — The schema behind the registry, and the evidence grades it enforces.