[0.3.0] — 2026年06月05日

Implements AHP 0.3.0.

Added

• McpServerCustomization now exposes the full MCP lifecycle: enabled,
  the discriminated McpServerState enum
  (.starting/.ready/.authRequired/.error/.stopped), optional
  channel URI for the mcp:// side-channel, and optional mcpApp
  block carrying AhpMcpUiHostCapabilities for MCP Apps.
• McpServerAuthRequiredState carries ProtectedResourceMetadata
  plus reason / requiredScopes / description so the existing
  authenticate command can drive per-server auth.
• Customization.mcpServer top-level case — hosts MAY surface bare
  MCP servers directly rather than only inside a plugin or directory.
• SessionMcpServerStateChangedAction and matching reducer arm —
  narrow upsert of state + channel on an existing MCP
  server customization by id. Wired through both Reducers.swift and
  the protocol-based NativeReducer.swift.
• ClientCapabilities struct on InitializeParams.capabilities with
  first entry mcpApps.
• changeKind field on Changeset (well-known values: 'session',
  'branch', 'uncommitted', 'turn', 'compare-turns').
• status and error fields on ChangesetOperation and the
  changeset/operationStatusChanged action, tracking the
  idle → running → error lifecycle of a changeset operation.
• AgentCustomization._meta provider metadata field.
• Optional changes field on SessionSummary (ChangesSummary with optional additions, deletions, and files counts) summarising a session's file-change footprint.

Changed

• Renamed the ChangesetSummary type to Changeset. The on-the-wire shape is unchanged.
• Moved the changesets catalogue from SessionSummary to SessionState. The session/changesetsChanged action now updates state.changesets directly instead of state.summary.changesets.

Removed

• Removed the additions, deletions, and files fields from ChangesetSummary. Aggregate counts now live on SessionSummary.changes; per-changeset views derive their own totals from ChangesetState.files.

Changed

• ToolCallBase.toolClientId: String? replaced by
  ToolCallBase.contributor: ToolCallContributor? (enum with
  .client(ToolCallClientContributor) and .mcp(ToolCallMcpContributor)
  cases). SessionToolCallStartAction carries the new contributor
  field as well. Reducers.swift, NativeReducer.swift, and
  ToolCallStateExtensions.swift follow the rename.

[0.3.0] — 2026年06月05日

Spec version: 0.3.0

Added

• McpServerCustomization now models MCP servers as first-class session
  customizations: enabled, state (a discriminated
  McpServerState union covering starting, ready, authRequired,
  error, stopped), an optional channel URI for an mcp://
  side-channel into the upstream server, and an optional mcpApp block
  carrying AhpMcpUiHostCapabilities so clients can render
  MCP Apps.
• McpServerAuthRequiredState carries ProtectedResourceMetadata plus
  reason / requiredScopes / description, letting clients drive the
  existing authenticate command for per-MCP-server auth challenges.
• Customization now includes McpServerCustomization at the top level
  (hosts MAY surface globally-configured MCP servers directly rather
  than only inside a plugin or directory). MCP servers remain valid as
  children of a container.
• New session/mcpServerStateChanged action — narrow upsert of
  state + channel on an existing McpServerCustomization
  by id, intended for the high-frequency
  starting/ready/authRequired transitions. Other customization
  fields stay in session/customizationUpdated territory.
• InitializeParams.capabilities — optional client-capability bag
  declared during the handshake. First entry is mcpApps?: {}; hosts
  SHOULD only populate McpServerCustomization.mcpApp / channel for
  clients that declared it.
• New guide page docs/guide/mcp.md (with an MCP Apps subsection) and
  new spec page docs/specification/mcp-channel.md.
• Added changeKind to Changeset (well-known values: 'session',
  'branch', 'uncommitted', 'turn', 'compare-turns') so clients can
  group, sort, or pick an icon without parsing uriTemplate.
• Added status and error to ChangesetOperation and a new
  changeset/operationStatusChanged action so servers can reflect an
  operation's execution lifecycle (idle → running → error) back into
  changeset state.

Changed

• Replaced ToolCallBase.toolClientId?: string with a discriminated
  ToolCallBase.contributor?: ToolCallContributor union
  (ToolCallClientContributor / ToolCallMcpContributor) so MCP-served
  tool calls can be attributed back to their originating
  McpServerCustomization. session/toolCallStart carries the new
  contributor? field in place of toolClientId?.

• Added optional _meta provider metadata to AgentCustomization.

• Added optional changes field of type ChangesSummary to SessionSummary,
  carrying optional additions, deletions, and files counts so servers
  can advertise an at-a-glance view of a session's file-change footprint.

• Removed the additions, deletions, and files fields from
  ChangesetSummary. Aggregate counts now live on SessionSummary.changes;
  per-changeset views derive their own totals from ChangesetState.files.

• Moved the changesets catalogue from SessionSummary to
  SessionState. The session/changesetsChanged action now updates
  state.changesets directly instead of state.summary.changesets.

• Renamed the ChangesetSummary interface to Changeset. The
  on-the-wire shape is unchanged.

• Renamed the UserMessage type to Message and surfaced it consistently
  across turn state (Turn.message, ActiveTurn.message, PendingMessage.message)
  and the actions that carry it (session/turnStarted,
  session/pendingMessageSet). The type now carries an origin field and an
  optional _meta object.

[0.2.0] — 2026年05月28日

Spec version: 0.2.0

This is the first version released through the unified spec release pipeline
(spec/v* git tags → GitHub Release with attached schema artifacts). Changes
to the protocol shape that landed under this version are tracked in the
commits between spec/v0.1.0 (not yet tagged) and spec/v0.2.0. Highlights:

• Channels reorganization — every command and notification carries a top-level
  channel: URI; per-channel state types and action unions live under
  types/channels-*/ (see PR #97 and PR #152).
• New otlp/* notifications for telemetry export
  (exportLogs / exportTraces / exportMetrics).
• New session/agentChanged, session/customizationRemoved,
  session/changesetsChanged, and the changeset/* action family.
• Customizations redesigned as a typed two-level tree.
• New resourceResolve (stat + realpath; throws NotFound for the
  existence check) and resourceMkdir (mkdir -p semantics) requests.
• New createResourceWatch request plus the ahp-resource-watch:/<id>
  channel with the resourceWatch/changed action — long-lived file-change
  streams over the standard subscription mechanism.
• resourceWrite extended with mode (truncate | append | insert),
  position, and ifMatch for optimistic concurrency. New
  Conflict (-32011) error code for stale ifMatch writes.
• The entire content-bearing resource* family is now formally
  bidirectional — the methods appear in ServerCommandMap and may be
  initiated by either peer (matches VS Code's existing implementation).
• UserMessage._meta optional Record<string, unknown> field for
  provider-specific message metadata, mirroring the MCP _meta convention
  already used on MessageAttachmentBase, ToolDefinition, ToolCallBase,
  UsageInfo, and SessionState.