spec/v0.3.0 v0.3.0
microsoft/agent-host-protocolJun 6, 2026 → Jun 6, 20260 days between releases
What's New
Both releases declare spec 0.3.0; the newer one is a re-publication with expanded notes and no protocol delta.
New Features
- Newer notes add a `ChangesetOperationStatus.disabled` case to the changeset operation status enum.
- Newer notes document an optional `changes` aggregate (`ChangesSummary` with additions/deletions) on `SessionSummary`.
- Newer notes surface an `AgentCustomization._meta` provider metadata field.
- Newer notes name the `changeset/operationStatusChanged` action explicitly for tracking operation lifecycle transitions.
Improvements
- Reducer support for the MCP server state-changed action is described as wired through both `Reducers.swift` and the protocol-based `NativeReducer.swift`.
- Release notes were expanded with more concrete field-level detail and well-known `changeKind` values.
- Client capability declaration during handshake is spelled out as a `ClientCapabilities` struct rather than an inline bag.
Upgrade Notes
Treat these as the same spec version: the breaking changes listed (contributor replacing toolClientId, ChangesetSummary renamed to Changeset, changesets moved to SessionState) apply to anyone coming from a pre-0.3.0 pin, not to this pair. If you already pin spec/v0.3.0, no code or schema changes are required. Re-read the newer notes only for the extra field details (disabled status, SessionSummary.changes, _meta).
The Two Releases
AHP Spec v0.3.0
Jun 6, 2026· 5 months ago
Core protocol update regarding MCP servers as first-class customizations and tool attribution.
Full release notesAHP Swift Package v0.3.0
Jun 6, 2026· 5 months ago
Adds full MCP server lifecycle management and changeset operation status tracking.
Full release notes