> ## Documentation Index
> Fetch the complete documentation index at: https://docs.agentvolumes.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Upstream PURL and VERS baselines

> Pinned upstream references used by Agent Volumes PURL and VERS compatibility fixtures.

Agent Volumes records upstream baselines so maintainers can explain which PURL and VERS references informed release-candidate validation fixtures. The artifact does not vendor those projects or turn their behavior into a general package-manager resolution policy.

## Current baselines

| Name               | Upstream                                                                             | Revision                                   | Purpose                                                                                                                                            |
| ------------------ | ------------------------------------------------------------------------------------ | ------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| `package-url-spec` | [https://github.com/package-url/purl-spec](https://github.com/package-url/purl-spec) | `1f8c6f2461cfe8dd3eda85eb6afa30d99b3cc6d0` | Pinned reference for PURL syntax, canonicalization, qualifier, version, and subpath semantics used by external dependency validation fixtures.     |
| `vers-spec`        | [https://github.com/package-url/vers-spec](https://github.com/package-url/vers-spec) | `ee7d8b44f22f1517c75f7229b57b79374c8d34e5` | Pinned reference for VERS syntax, canonical constraints, and scheme-specific comparison semantics used by external dependency validation fixtures. |

## Canonical artifacts

* [`conformance/upstream-baselines.json`](https://github.com/agent-volumes/agent-volumes-spec/blob/main/conformance/upstream-baselines.json)
* [`schemas/upstream-baseline.schema.json`](https://github.com/agent-volumes/agent-volumes-spec/blob/main/schemas/upstream-baseline.schema.json)

## Related sources

* [PURL and VERS compatibility exceptions](/spec/0.1.0-rc.1/uri-publications/purl-vers-compatibility-exceptions)
* [Conformance fixtures](/spec/0.1.0-rc.1/conformance/fixtures)
* [ADR-0126](https://github.com/agent-volumes/agent-volumes-spec/blob/main/docs/decisions/0126-record-upstream-purl-and-vers-baselines-in-a-machine-readable-manifest.md)