At a glance
Choosing today: new production integrations should use 3.1 with wire pin "3.1". Existing 3.0 integrations can remain pinned to "3.0" while they migrate.
| Status | Versions | Wire pin | What it means |
|---|
| Active | 3.1 (current stable: 3.1.0) | "3.1" | Current production minor release. See What’s New in AdCP 3.1 for the feature set. |
| Maintained | 3.0 (current stable: 3.0.19) | "3.0" | Supported previous minor for existing production integrations. Receives compatibility and security patches. |
| Security-only | 2.5.0, 2.5.1, 2.5.3 | "2.5" | Security patches through August 1, 2026 (UTC). Not safe for AAO-network production — see v2 sunset. |
| End of life | 2.0.0, 2.1.0 | — | No patches. Migrate to 3.0. |
| Planned | 3.2, 4.0 | — | Targets in planned releases. |
"3.1" for the stable 3.1 line or "3.0" for the maintained 3.0 line. Do not send patch components like "3.0.19" or full semver pre-release values like "3.1.0-rc.15". Historical prerelease pins such as "3.1-rc.15" remain valid only for agents that explicitly advertise those prerelease values. See patches are not negotiated.
Status legend: Active = current stable generation. Maintained = supported previous minor. Security-only = patches for security issues only, no features. End of life = no patches. Planned = not yet released.
All published versions
3.x — current generation
| Version | Released | Notes |
|---|
| 3.0.0 | 2026-04-22 | GA — stable baseline for the 3.x cycle. |
| 3.0.1 through 3.0.10 | 2026-04-28 to 2026-05-10 | Patches. Wire-compatible with 3.0.0. |
| 3.0.11 through 3.0.15 | 2026-05-11 to 2026-05-31 | Patches. Wire-compatible with 3.0.0. |
| 3.0.16 through 3.0.19 | 2026-06-14 to 2026-06-17 | Patches. 3.0.19 is the latest stable patch. Wire-compatible with 3.0.0. |
| 3.1.0 | 2026-06-18 | GA — current production minor release. Use wire pin "3.1". |
Prereleases (superseded)
| Version | Released | Notes |
|---|
| 3.1.0-rc.1 through 3.1.0-rc.15 | 2026-05-29 to 2026-06-16 | Superseded by 3.1.0 GA. These artifacts remain available for pinned prerelease adopters and release forensics. |
| 3.0.0-beta.1 through rc.2 | 2026-01-26 to 2026-03-15 | Superseded. |
| 3.0.0-rc.3 | 2026-04-01 | Superseded by GA. See prerelease upgrade notes if you adopted rc.3. |
2.x — sunsetting
| Version | Released | Notes |
|---|
| 2.0.0 | 2025-10-15 | End of life. No patches. Migrate to 3.0. |
| 2.1.0 | 2025-10-19 | End of life. No patches. Migrate to 3.0. |
| 2.5.0 | 2025-11-22 | Security-only through Aug 1, 2026 (UTC). |
| 2.5.1 | 2025-12-24 | Security-only through Aug 1, 2026 (UTC). |
| 2.5.3 | January 2026 | Security-only through Aug 1, 2026 (UTC). Last 2.x release. |
FAQ
What’s “current”?
For new production integrations, 3.1.0 is current; pin your integration to "3.1" (not "3.1.0"). Existing 3.0 integrations can remain pinned to "3.0" while they migrate. See Version negotiation.
What happened to 2.2, 2.3, 2.4, 2.6?
The 2.x line skipped version numbers during its working-group cycle. Some appear as in-flight changelog entries but were never released — the changes were rolled forward into the next published version or deferred to 3.0. The five published 2.x releases are 2.0.0, 2.1.0, 2.5.0, 2.5.1, and 2.5.3.
Can I still register a v2 agent?
Yes — v2 agents can be registered in the AAO registry but cannot be AAO Verified. Certification and verified-default discovery require v3.x. See v2 Sunset → If you use the AAO registry.
How long will 3.0 be supported?
At least 12 months after 4.0 GA. See Versioning → Support window for previous major.
Where is 4.0?
Targeted for early 2027. 3.x is mid-cycle — see the planned releases table.
Choosing a version
| If you are… | Use |
|---|
| Building a new production integration today | 3.1. Pin "3.1" on the wire. |
| Running an existing 3.0 integration | Stay on 3.0 while you migrate, or move to 3.1 when your SDK and validation are ready. |
| Running a 2.5.x integration | Migrate to 3.0 before Aug 1, 2026 (UTC). Start with the migration guide. |
| Running a 2.0 or 2.1 integration | Upgrade now — out of support. |
| Trying a post-3.1 unreleased feature | See Release Notes, Versioning & Governance, and experimental status. |
