ACP codebuddy.ai/* Extension Namespace Reference

A complete inventory of CodeBuddy's private extensions on ACP (Agent Client Protocol): _meta extension keys + _codebuddy.ai/* extension methods.

Intended for two audiences: ① Third-party ACP clients (Zed, etc.) — wanting to know which extensions can be read and which should never be self-fabricated; ② CodeBuddy / WorkBuddy internal developers — when modifying the admission chain, needing to know which key belongs to the standard surface and which to the multi-tenant private channel.

0. The Most Important Rule: The Standard ACP Surface Works with Zero _meta

The entire initialize / session/new / session/prompt chain of cbc --acp can function without a single codebuddy.ai/* _meta key, and must be fully usable. This is a hard contract, not "it happens to work right now."

Mechanistically guaranteed by the process-login composition root (profiles cbc-tui / cbc-headless / agent-sdk-js-single):

• src/node/session/process-login-admission-authority.ts — maintains its own transport credential and principal in-process; issueMainAdmission() constructs the admission envelope and its grant in the same place;
• src/node/session/process-login-acp-admission-service.ts:60-84 — admitAndActivate() wholly replacesmetadata with this process's self-produced ticket. The original comment is the contract: "client _meta does not participate in identity decisions at all."

External ACP clients neither can nor should construct a runtime admission envelope, so this zero-meta path is the only correct form for the standard surface.

Standing defense: src/e2e/acp-zero-meta-contract.spec.ts — drives bin/codebuddy --acp with bare stdio NDJSON, runs initialize → session/new → session/prompt entirely with zero meta, and flags any "missing … metadata" error as red.

Contrast surface: multi-owner-headless uses the session-payload composition root, whose session/newmandates explicitly carrying _meta['codebuddy.ai/sessionAdmissionV2'] (see runtime-admission-acp-adapter.ts:47-48 throwing ACP Session request is missing sessionAdmissionV2 metadata). That is a private channel, not an ACP protocol requirement — the difference between the two composition roots is only "who produces the envelope," and is unrelated to the standard surface.

C3 Change (workbuddy-single form officially named B1): WorkBuddy desktop (workbuddy-single) and workbuddy-completion-warm have changed from "per-session wire identity envelope" to process-level identity injection — the daemon injects a one-time owner authorization after initialize via _codebuddy.ai/activateWorkbuddyOwnerRuntime (warm side: _codebuddy.ai/activateCompletionRuntime), after which the CLI process self-produces the envelope. These two surfaces' session/new no longer carries sessionAdmissionV2 / authSession, retaining only the launcher's runtimeTransportCredential (transport authentication invariant, verified each time before self-signing) and two non-identity business authorization keys sessionGrantV1 / completionDispatchGrantV1 (§3.1).

The production surface for sessionAdmissionV2 converges to three locations, only the first still goes over the daemon→CLI wire: ① host control sidecar (daemon-side workbuddy-host-control-authority.ts); ② teammate leader self-signs in-process and distributes to children via the bootstrap channel (workbuddy-admission-security.ts issueTeammateAdmissionMetadata); ③ after C3, the main envelope self-signed in-process by workbuddy-single / completion-warm (same file: issueMainAdmissionMetadata / issueCompletionDispatchMetadata).

1. Classification Terminology

Label	Meaning
Public	Public optional extension. Visible or optionally carried on the standard ACP surface (cbc --acp); absence does not affect protocol usability; third-party clients can safely read and optionally ignore.
Private	Multi-tenant private channel, session-payload composition root only (WorkBuddy daemon ↔ CLI, multi-owner-headless) produces and consumes. Third-party ACP clients must not produce these keys; the standard surface will never require them.

Direction notation: A→C = Agent sends to Client (response / notification); C→A = Client sends to Agent (request parameters); Bidirectional = appears in both directions.

2. Inventory Reconciliation

Line number anchor disclaimer: All file:line anchors in this document correspond to the source code at the time of writing (and most recent review) and are for quick navigation only; line numbers will inevitably drift as the source evolves. Grep by "file + referenced text / symbol" is authoritative; line numbers are auxiliary.

Canonical grep (reproducible):

# Run at the genie repo root; git grep naturally excludes build artifacts like node_modules / dist / lib / out-tsc
git grep --untracked -hoE "codebuddy\.ai/[A-Za-z0-9_.-]*" -- 'packages/**/*.ts' 'packages/**/*.tsx' | sort -u | wc -l
# => 195 (deduplicated token count)

--untracked is required: without it, only tracked files are counted, and any new source files not yet committed would be missed, causing the reconciliation number to drift with commit timing. Only reconcile token counts, not hit line counts — line counts are sensitive to unrelated comment changes and cannot form a stable anchor.

Note: the -oE character class does not include /, so _codebuddy.ai/foo produces the token codebuddy.ai/foo (dropping the leading underscore), and _codebuddy.ai/session/rollback produces codebuddy.ai/session. 195 is the token count, not the key count, and must be partitioned into the four buckets below to equal the true inventory.

195 = 142 + 44 + 3 + 6, each item traceable within this document:

Bucket	Count	What it is	Where in this doc
A	142	Actual _meta extension keys	§3 (all listed)
B	44	JSON-RPC extension method/notification names (_codebuddy.ai/*), with underscore stripped by grep	§4 (all listed)
C	3	Namespace prefixes / wildcard patterns, not independent keys	§5.1
D	6	Product site URL path false positives (https://www.codebuddy.ai/...)	§5.2

C3 reconciliation change (194→195): Bucket A net unchanged (removed completionDispatchId / completionExecutionDigest, added sessionGrantV1 / completionDispatchGrantV1); Bucket B 43→44 (added _codebuddy.ai/activateWorkbuddyOwnerRuntime).

Discrimination method (reproducible): For each token, check the preceding character where it appears in the source — _ ⇒ extension method (B), . or / ⇒ URL (D), otherwise ⇒ _meta key (A); then pick out wildcard prefixes that "can be followed by / or *" (C).

3. Complete _meta Extension Key Inventory (142 entries)

3.1 Admission / Identity / Credentials (14 entries)

This group is where the "public vs private" boundary matters most.

Key	Direction	Classification	Producer	Consumer	Semantics
runtimeAdmission	A→C	Public	CLI, runtime-admission-acp-adapter.ts:10-11,30-39 (initialize response)	session-payload side daemon (constructs envelope from this); standard surface clients can ignore	Process admission handshake: schemaVersion / runtimeProfile / runtimeConfigSha256 / processInstanceId / handshakeNonce. Both composition roots send it; zero-meta e2e uses it to anchor runtimeProfile === 'cbc-headless'
sessionAdmissionV2	C→A	Private	multi-owner issuer (out-of-process signing); WorkBuddy family now only the host control sidecar (workbuddy-host-control-authority.ts)	runtime-admission-acp-adapter.ts:47-53, multi-owner-acp-admission-service.ts:164	Admission envelope for session/new / session/load. Missing ⇒ ACP Session request is missing sessionAdmissionV2 metadata. process-login and post-C3 workbuddy-single / completion-warm are all self-produced by the CLI; clients need not and should not carry it
sessionGrantV1	C→A	Private	daemon, workbuddy-runtime-admission.ts buildSessionGrantMetadata (added in C3)	workbuddy-single-admission-authority.ts readWorkbuddySessionGrant (assembled in workbuddy-single only)	Non-identity business authorization still needed on the wire after identity is removed from _meta: canonicalSessionId (daemon's session primary key, asserted by captureRuntimeBinding to be equal on return) / environment.values (the sole delivery channel for session incremental env on the prewarm hit path) / workspace{root,cwd,allowedRoots}. Does not participate in identity decisions; the standard ACP surface does not read this key
completionDispatchGrantV1	C→A	Private	daemon, workbuddy-runtime-admission.ts buildCompletionDispatchGrantMetadata (added in C3)	workbuddy-single-admission-authority.ts readWorkbuddyCompletionDispatchGrant (assembled in completion-warm only)	Per-dispatch execution authorization for completion warm: executionSubPolicyId + its digest / dispatchId / executionDigest / workspace. Identity comes from process-level injection; the execution ceiling is still per-dispatch from the daemon; missing this key triggers fail-closed
authSession	C→A	Private	daemon (session-payload identity seed)	acp-agent.ts:2141-2143 → per-session auth holder	{ auth: { accessToken, tokenType?, domain?, refreshToken? }, account?: { uid? } }. The account field is always derived from JWT; client self-reported values are never trusted
productConfig	C→A	Private	daemon (workbuddy-server/src/agent/cli-product-env.ts:170)	acp-agent.ts:2144-2146	Per-session product config injection: endpoint / networkEnvironment
runtimeTransportCredential	Bidirectional	Private	Admission core (multi-owner-acp-admission-service.ts:38-39, host-teammate-admission-security.ts:41)	Same	One-time credential bound to transport, used to prove connection identity at admit time
runtimeSessionBindingV2	A→C	Private	multi-owner-acp-admission-service.ts:40-41, workbuddy-session-admission-authority.ts:18	daemon	Exact binding projection returned after successful admission: ownerId / ownerGeneration / canonicalSessionId / sessionGeneration / resourceId
runtimeBindingToken	C→A	Private	daemon	agent-client-protocol/src/common/runtime-wire-authority.ts:1, acp-agent.ts:2147-2155	Binding token for wire requests; non-empty string or RUNTIME_BINDING_TOKEN_INVALID
runtimeAuthority	Bidirectional	Private	daemon / CLI	runtime-wire-authority.ts:2	Wire fencing authority snapshot (processIncarnation / connectionEpoch / owner / session / run generations); mismatch throws RUNTIME_*_STALE
teamNamespaceActivation	C→A	Public	Leader injects when starting teammates (host-teammate-launch.ts:138, workbuddy-teammate-launch.ts:124)	teammate child process	Team namespace activation declaration. Shared by both composition roots, not session-payload exclusive; third-party clients will not encounter it. Constraint: the sole consumption channel is the teammate bootstrap startup chain (teammate-runner.ts:272 reads from the bootstrap metadata returned by receiveWorkbuddyTeammateBootstrap), not client _meta on the ACP wire; third-party clients producing this key on the standard ACP surface will not have it consumed by any path
userinfo	A→C	Public	acp-agent.ts:1963-1974 (authenticate response)	Client UI	Logged-in user info: userId / userName / userNickname / enterpriseId / enterpriseName / authType
accessToken	——	Private	No producer (does not exist in protocol)	——	Only appears in log redaction coverage use case (workbuddy-core/.../conversation-file-logger.spec.ts:44): verifies that "token keys with namespace prefix are also [redacted]". Listed here to prevent future misinterpretation as a usable key
homeDir	——	Public	Retired	——	Retired dead field; both production and consumption code have been physically deleted (D6-7): the only repo-wide hit is a reverse guard test settings-persession-invariants.spec.ts:10, asserting that acp-agent.ts no longer contains this key — there is not even a legacy compat read side; clients carrying it will not have it read by any path. homeDir is always derived from JWT (resolveControlledHomeDir). Retained only for "do not re-enable this key name" documentation purposes

3.2 Request Correlation and Tracing (16 entries)

All Public: Agent echoes them on the _meta of responses / notifications; clients can optionally consume; requestId / messageRequestId / userMessageId / messageId also accept client-side pre-sending on session/prompt (acp-agent.ts:2925-2938); if absent, the CLI self-produces them.

Key	Direction	Producer	Semantics
requestId	Bidirectional	acp-agent.ts:2925,3412	Full-chain correlation ID for a single model request (highest hit count key)
messageId	Bidirectional	acp-agent.ts:2937,3349	Message-level ID
messageRequestId	Bidirectional	acp-agent.ts:2932,3423	Message ↔ request correlation ID
userMessageId	Bidirectional	acp-agent.ts:2931	User message ID (also echoed in session/prompt response)
promptRequestId	Bidirectional	acp-agent.ts:3415-3416	Business correlation ID generated by Renderer for each send/resend, for Desktop instrumentation + Galileo tracing
clientRequestId	C→A	Client	Client-defined correlation ID on tool calls (workbuddy-server/src/session/handlers.ts:1634)
modelRequestId	A→C	acp-view.ts:694	Model-side request ID
traceId	A→C	acp-agent.ts:3075	CLI-side trace ID
traceparent	A→C	acp-agent.ts:2866,3429	W3C traceparent echoed so the renderer's stream_render span can attach under prompt.send
runId	A→C	acp-agent.ts:263	SessionRunStateMachine's run ID
runStateRevision	A→C	acp-agent.ts:262	Run state snapshot revision
agentPhase	A→C	acp-agent.ts:261	Agent execution phase (AgentPhaseInfo)
timestamp	A→C	acp-timestamp-meta.ts:124-128	Timestamp (the flat key is removed during normalization, unified through the canonical location)
sendTime	C→A	Renderer	User send-click timestamp, for message-level user-perspective TTFT calculation (galileo-timing-hook.ts:110)
lfConvId	A→C	Upstream	LF conversation ID (flat passthrough, agent-ui/src/adapters/acp-message-accumulator.spec.ts:1132)
lfConvReqId	A→C	Upstream	LF conversation request ID (same)

3.3 Session Attributes and Modes (14 entries)

Key	Direction	Classification	Producer → Consumer	Semantics
mode	Bidirectional	Public	acp-agent.ts:2984,3072	Scene mode
userId	C→A	Public	Renderer → session.meta (acp-agent.ts:2888)	User ID for instrumentation / trace attributes (does not participate in identity decisions; identity only trusts JWT)
conversationId	Bidirectional	Public	acp-agent.ts:2889 / workbuddy-app/.../stream-span-manager.ts:144	Upstream conversation ID
locale	C→A	Public	acp-agent.ts:2890 (compatible with language)	Language / locale
expertId	Bidirectional	Public	acp-agent.ts:2891,2987	Expert ID
expertSelection	A→C	Public	workbuddy-server/.../expert-selection-reminder.ts:7	Expert selection reminder block marker
parentSessionId	A→C	Public	acp-protocol.ts:319,342	Parent session ID for sub-agent sessions
isSubAgent	A→C	Public	acp-protocol.ts:319,342	Whether this is a sub-agent session (note the different casing from isSubagent below — a historical legacy double-write)
isSubagent	A→C	Public	api-schema.ts:1803, use-acp.ts:284	Tool-call-level "is this a sub-agent call"
subagentType	A→C	Public	api-schema.ts:1804	Sub-agent type (default general-purpose)
isBackground	A→C	Public	api-schema.ts:1805	Whether running in background
isPlayground	A→C	Public	stream-span-manager.ts:148	Whether this is a playground scenario
continue	C→A	Public	acp-agent.ts:2560	Declares "continue last conversation" on session/new
sessionControl	Bidirectional	Public	workbuddy-core/.../conversation-prompt-operations.ts:12	Session control command payload

3.4 Session Lifecycle and Errors (12 entries)

Key	Direction	Classification	Producer	Semantics
errorMessage	A→C	Public	acp-agent.ts:414,3066	Human-readable error message accompanying stopReason: 'refusal'
finishReason	A→C	Public	acp-view.ts:703	Model finish reason
outcome	A→C	Public	acp-agent.ts:3087-3088	Prompt result verdict (SUCCESS, etc.)
businessFailed	A→C	Public	acp-utils.ts:1004	Business failure marker, for UI renderer to distinguish from transport failure
cancelReason	A→C	Public	acp-protocol.ts:973	Cancellation reason
cancelCause	A→C	Public	automation-prompt-builder.ts:285	Cancel cause on prompt result (automation reads this first)
terminationReason	A→C	Public	acp-broadcast-service.ts:435	Termination reason (e.g., prompt_timeout)
promptFailurePhase	A→C	Public	workbuddy-server/src/backend/prompt-replay-safety.ts:2	Phase where prompt failure occurred
promptFailureReason	A→C	Public	Same :3	Prompt failure reason
promptReplaySafe	A→C	Public	Same :1	Whether this failure is safe to replay
transportLost	A→C	Public	workbuddy-agent-adapter-next.ts:10689	Transport connection lost marker
transportError	A→C	Public	Same :10690	Transport error code (e.g., ws_rpc_connection_lost)

3.5 Tool Call Extensions (20 entries)

All Public; the vast majority are centrally copied from provider data to toolCallMeta in a single block at acp-agent.ts:5013-5064.

Key	Producer	Semantics
toolName	acp-agent.ts:4093,4168	Tool name
toolCallId	acp-broadcast-service.ts:287	Associated tool call ID
parentToolCallId	acp-agent.ts:3949,4004	Parent tool call ID (sub-agent nesting)
toolCancelReason	acp-agent.ts:578	Tool cancel reason (permission_denied used to distinguish from normal cancellation)
toolFailReason	acp-agent.ts:650	Tool failure reason classification
toolResultTitle	persisted-transcript-projector.ts:72	Tool result title (for transcript projection)
description	acp-agent.ts:5047,6344	Tool call description
operation	acp-agent.ts:5046,6343	Operation type (e.g., mcp-ui reverse tools/call)
target	acp-agent.ts:5045,6342	Operation target (e.g., MCP server name)
filename	acp-utils.ts:654	Associated filename
images	acp-broadcast-service.ts:684	Image payload
rawResponse	acp-utils.ts:997	Tool raw structured result, passed through to UI renderer (e.g., web-search)
bulkDeleteInfo	acp-agent.ts:5059-5060	Bulk delete info
bypassHint	acp-agent.ts:5056-5057	Bypass hint
interceptType	acp-agent.ts:5044,6758	Intercept type
sandboxIntercept	acp-agent.ts:5013,5043	Sandbox intercept marker
sandboxApprovalMode	acp-agent.ts:5053-5054	Sandbox approval mode
mcpUiIntercept	acp-agent.ts:4853,6341	MCP-UI reverse call intercept marker
hook	acp-utils.ts:770, session-manager.ts:766	Hook structured block info
details	acp-agent.ts:6800	Event supplementary details

3.6 Permissions / Plans / Goals (8 entries)

All Public.

Key	Producer	Semantics
decision	acp-broadcast-service.ts:289	Permission decision result
permissionResolved	acp-broadcast-service.ts:286	Permission resolved notification
planContent	api-schema.ts:1808	ExitPlanMode plan body
goalProgress	use-acp.ts:491-492	Goal progress
goalRecap	acp-broadcast-service.ts:487	Goal recap
goalStatus	use-acp.ts:522-523	Goal status
interruptionRequest	acp-broadcast-service.ts:221, session-replay.ts:692	Interruption (HITL) request payload
promptSuggestion	prompt-suggestion-service.ts:502	Prompt suggestion

3.7 History Replay and Transcript Projection (10 entries)

Key	Direction	Classification	Producer	Semantics
historyReplay	A→C	Public	session-replay.ts:392	History replay boundary marker (start / end)
historyReplayTotalItems	A→C	Public	session-replay.ts:393	Total replay item count (only at start)
rendererHistoryReplay	A→C	Public	conversation-frame-classifier.ts:83, replay-event-classifier.ts:82	Renderer replay marker
ownerSnapshotHistoryReplay	A→C	Private	replay-event-classifier.ts:87, conversation-frame-classifier.ts:84	Owner snapshot replay marker — the owner concept only holds under session-payload multi-tenancy
isSessionSeparator	A→C	Public	conversation-frame-classifier.ts:91	Session separator frame marker
separatorExtra	A→C	Public	Same :94	Separator frame additional info
createTime	A→C	Public	Same :93	Frame creation time
offset	A→C	Public	workbuddy-agent-adapter-next.ts:6458	Transcript source offset (legacy key)
sourceOffset	A→C	Public	agent-member-utils.ts:242, team-runtime.ts:461	Transcript source offset (new key, takes priority over offset)
originalBytes	A→C	Public	persisted-transcript-projector.ts:71	Original byte count before transcript truncation

3.8 Context Compaction (6 entries)

All Public, via session_info_update._meta.

Key	Producer	Semantics
compactType	context-protocol.ts:231	Compaction type; desktop adapter decides presentation based on this
compactStatus	conversation-frame-classifier.ts:231	Compaction status
compact-cancelled	context-protocol.ts:287	{ cancelled: true } — compaction was cancelled
compact-limit-reached	context-protocol.ts:295	{ limitReached: true } — compaction limit reached
compactTruncated	persisted-transcript-projector.ts:70	This frame was truncated during compaction
isCompactInternal	acp-agent.ts:3200,3396	This prompt was internally triggered by compact (not counted as a user-visible turn)

3.9 Team / Teammate (7 entries)

Key	Direction	Classification	Producer	Semantics
teamUpdate	A→C	Public	acp-team-bridge.ts:745,779	Team status event (member status change, etc.)
memberEvent	A→C	Public	acp-team-bridge.ts:602	Attribution tag for member streaming messages (member name)
memberName	A→C	Public	acp-agent.ts:5037	Member name owning the tool call
isTeamMember	A→C	Public	acp-agent.ts:5036	This tool call is from a team member
agentColor	A→C	Public	acp-agent.ts:5039	Member display color
syntheticTeammateMessage	A→C	Public	team-runtime-loader.ts:691, workbuddy-agent-adapter-next.ts:4945	Synthetic teammate message (not directly from model)
teammateSummary	A→C	Public	Same :693 / :4946	Teammate summary text

3.10 Workflow (14 entries)

All Public, centrally produced at src/node/workflow/acp/workflow-acp-bridge.ts:146-190, with a unified codebuddy.ai/workflow* key space.

Key	Line	Semantics
workflowEventKind	:151	Event type
workflowRunId	:156,168	Run ID
workflowName	:157	Workflow name
workflowStatus	:158	Run status
workflowAgentCount	:159	Total agent count
workflowCachedCount	:160	Cached agent count
workflowPhaseCount	:161	Total phase count
workflowError	:163	Run-level error
workflowPhase	:169	Current phase
workflowAgentKey	:175	Agent key
workflowAgentLabel	:177	Agent display name
workflowAgentPhase	:180	Agent phase
workflowAgentError	:183	Agent-level error
workflowAgentTokens	:186	Agent token consumption

3.11 External Channel Access (6 entries)

All Public, produced by acp-utils.ts:481-491 and consumed by Web UI use-acp.ts:202-213. Carries source information for external channels such as WeCom.

Key	Semantics
channelSource	Channel source identifier
channelSender	Sender ID
channelSenderName	Sender display name
channelChatId	Conversation ID
channelChatType	Conversation type (single / group)
commandKind	Command kind (slash)

3.12 MCP-UI and Message Queue (4 entries)

Key	Direction	Classification	Producer	Semantics
sendMessageMode	C→A	Public	MCP-UI widget (mcp-app-handlers.ts:79,112)	Widget write-back message behavior routing: send / fill
message_queue_update	A→C	Public	acp-broadcast-service.ts:462	Message queue incremental update
newSessionId	A→C	Public	acp-command-attachment-router.ts:73	New sessionId after command triggers new session creation
sessionReset	A→C	Public	acp-command-attachment-router.ts:72	Session was reset (e.g., /clear)

3.13 Content and Usage (5 entries)

Key	Direction	Classification	Producer	Semantics
usageByCategory	A→C	Public	acp-protocol.ts:64,1331	Categorized usage for usage_update; invariant: sum(usageByCategory) === update.used
contentFilterNotice	A→C	Public	context-protocol.ts:258	Content filter notice (true means this text block is a filter notification)
hiddenPromptContext	C→A	Public	colleague-mention-context.ts:15	This prompt block is hidden context, not rendered in UI
progress	A→C	Public	acp-agent.ts:3820, stream-json-protocol.ts:554	Progress payload on session_info_update
sourceEvent	A→C	Public	acp-utils.ts:146	Objective description of this update's source event (facets), for adapter dispatching

3.14 Model Identification (4 entries)

All Public, centrally backfilled at acp-agent.ts:3437-3447.

Key	Semantics
requestModelId	Model ID used for the request
requestModelName	Model name used for the request
responseModelId	Actual response model ID
responseModelName	Actual response model name (conversation-event-machine.ts:334)

3.15 Completion Warm and Others (2 entries)

C3 change: completionDispatchId / completionExecutionDigest two flat keys have been physically deleted along with buildEphemeralMetadata; their semantics are merged into §3.1's completionDispatchGrantV1 (structured per-dispatch execution authorization).

Key	Direction	Classification	Producer	Semantics
status	A→C	Public	acp-session-info-router.ts:136-137, conversation-event-machine.ts:763	Status field for session_info_update
model	A→C	Public	stream-span-manager.ts:145	Flat model name (for span attribution)

Private key subtotal (10 entries): sessionAdmissionV2, sessionGrantV1, completionDispatchGrantV1, authSession, productConfig, runtimeTransportCredential, runtimeSessionBindingV2, runtimeBindingToken, runtimeAuthority, ownerSnapshotHistoryReplay — plus accessToken which "has no producer but belongs to the credential surface", totaling 11 entries that never appear on the standard ACP surface. The remaining 131 entries are public optional extensions.

4. Complete _codebuddy.ai/* Extension Method / Notification Inventory (44 entries)

ACP requires custom methods to use underscore prefix + reverse domain namespace. These are not _meta keys, but share the same namespace; third-party clients likewise need to know their public / private classification. Inventory entry: packages/agent-client-protocol/src/common/types.ts:25-35.

Method Name	Direction	Classification	Semantics
_codebuddy.ai/question	A→C (request)	Public	HITL question, waiting for client response (acp-protocol.ts:900)
_codebuddy.ai/resolveInterruption	C→A (request)	Public	Client answers interruption request (acp-agent.ts:5565-5570)
_codebuddy.ai/artifact	A→C (notify)	Public	Artifact push (session-replay.ts:523)
_codebuddy.ai/command	A→C (notify)	Public	Command event (types.ts:25)
_codebuddy.ai/checkpoint	A→C (notify)	Public	Checkpoint event (session-replay.ts:601)
_codebuddy.ai/session/rollback	C→A (request)	Public	Session rollback (acp-agent.ts:5812)
_codebuddy.ai/session/rollbackFiles	C→A (request)	Public	File-level rollback
_codebuddy.ai/session/previewFileRollback	C→A (request)	Public	Rollback preview
_codebuddy.ai/file_history_snapshot	A→C (notify)	Public	File history snapshot (types.ts:29)
_codebuddy.ai/fileTreeChanged	A→C (notify)	Public	File tree changed (must include filePath)
_codebuddy.ai/authUrl	A→C (notify)	Public	Login redirect URL (types.ts:27)
_codebuddy.ai/getUserInfo	C→A (request)	Public	Fetch user info (acp-agent.ts:5578)
_codebuddy.ai/uiControl	A→C (request)	Public	UI control command (types.ts:35)
_codebuddy.ai/system_init	A→C (notify)	Public	System initialization notification
_codebuddy.ai/tool_input	A→C (request)	Public	Tool input inquiry (agent-provider/examples/question-example.ts:16)
_codebuddy.ai/delegateTool	A→C (request)	Public	Tool proxy execution (delegate-tool-manager.ts:299)
_codebuddy.ai/delegateToolsChanged	C→A (notify)	Public	Client delegatable tool set changed (acp-agent.ts:5580)
_codebuddy.ai/refreshPlugins	C→A (request)	Public	Request plugin refresh (acp-agent.ts:5584)
_codebuddy.ai/plugins_changed	A→C (notify)	Public	Plugin set changed
_codebuddy.ai/mcp_servers_changed	A→C (notify)	Public	MCP server set changed
_codebuddy.ai/models_changed	A→C (notify)	Public	Model list changed
_codebuddy.ai/product_config_changed	A→C (notify)	Public	Product config changed
_codebuddy.ai/identity_changed	A→C (notify)	Public	Identity change broadcast (broadcast to all live sessions after main process writes)
_codebuddy.ai/queue_state_changed	A→C (notify)	Public	Queue state changed
_codebuddy.ai/message_queue_snapshot_changed	A→C (notify)	Public	Message queue snapshot changed
_codebuddy.ai/automation_snapshot	A→C (notify)	Public	Automation snapshot
_codebuddy.ai/interaction_timeout	A→C (notify)	Public	Interaction timeout (cloud-agent-event-bridge.ts:10)
_codebuddy.ai/teams	A→C (notify)	Public	Team SSE event (use-collab-queue.ts:5)
_codebuddy.ai/conversation	A→C (notify)	Public	Conversation event (use-conversation-events.ts:50)
_codebuddy.ai/mcpUiCallTool	C→A (request)	Public	MCP-UI reverse tools/call
_codebuddy.ai/mcpUiReadResource	C→A (request)	Public	MCP-UI read resource
_codebuddy.ai/mcpUiUpdateModelContext	C→A (request)	Public	MCP-UI update model context
_codebuddy.ai/mcpUiRequestDisplayMode	C→A (request)	Public	MCP-UI request display mode
_codebuddy.ai/mcpUiResourceTeardown	C→A (request)	Public	MCP-UI resource teardown
_codebuddy.ai/respondToSandboxIntercept	C→A (request)	Public	Respond to sandbox intercept (codebuddy-code-backend.ts:1909)
_codebuddy.ai/admitControl	C→A (request)	Private	Control Session admission. process-login composition root directly throws (process-login-acp-admission-service.ts:87-90), only used by workbuddy-host-sidecar
_codebuddy.ai/runtimeCredentialUpdate	C→A (request)	Private	per-session exact credential update (acp-agent.ts:5595)
_codebuddy.ai/runtimeControlCredentialUpdate	C→A (request)	Private	control binding credential update (acp-agent.ts:5597)
_codebuddy.ai/runtimeOwnerCredentialUpdate	C→A (request)	Private	owner-level bulk credential update (acp-agent.ts:5599), corresponds to bulkApplyExactCredentialUpdates
_codebuddy.ai/activateWorkbuddyOwnerRuntime	C→A (request)	Private	Added in C3: injects a one-time owner authorization into the workbuddy-single process (authSession + product material + credential handle), after which session/new needs zero identity meta. Payload = {proof, processInstanceId, handshakeNonce, runtimeConfigSha256, ownerGeneration}, validation point workbuddy-admission-security.ts activateOwnerRuntime
_codebuddy.ai/activateCompletionRuntime	C→A (request)	Private	Activate completion warm runtime; from C3, claims append credentialMaterial, simultaneously serving as the warm side's process-level owner injection, and after credential refresh, it is called again with the same ownerGeneration and a new proof (full replacement semantics)
_codebuddy.ai/completionDispatch	C→A (request)	Private	Dispatch a completion (acp-agent.ts:5738)
_codebuddy.ai/completionRuntimeDiagnostics	C→A (request)	Private	Completion runtime diagnostics (acp-agent.ts:5708)
_codebuddy.ai/disposeEphemeralSession	C→A (request)	Private	Destroy ephemeral session (acp-agent.ts:5676)
_codebuddy.ai/disposePersistentSession	C→A (request)	Private	Destroy persistent session (acp-agent.ts:5705)
_codebuddy.ai/example	——	——	Test-only placeholder method name, only appears in workbuddy-server/src/server-owned-handlers.spec.ts:2113, no production implementation

46 rows in the table = 44 grep tokens + session/rollbackFiles / session/previewFileRollback two sub-paths (they share the token codebuddy.ai/session with session/rollback; grep counts it only once).

5. Non-Key Hits (9 entries)

5.1 Namespace Prefixes / Wildcard Patterns (3 entries)

Token	Occurrence Form	Description
codebuddy.ai/	startsWith('codebuddy.ai/') / startsWith('_codebuddy.ai/')	The namespace prefix itself. Guard points: workflow-acp-bridge.spec.ts:82, sandbox-proxy/src/handler/artifacts-proxy.ts:70, sandbox-proxy/src/replay/replay.ts:1047
codebuddy.ai/workflow	codebuddy.ai/workflow* in comments	Key space wildcard pattern (workflow-acp-bridge.ts:146), not an independent key
codebuddy.ai/mcpUi	_codebuddy.ai/mcpUi* in comments	Wildcard pattern for 5 MCP-UI extension methods (mcp-apps-extmethod.spec.ts:4)

5.2 Product Site URL Path False Positives (6 entries)

The following tokens come from URLs like https://www.codebuddy.ai/... / https://code.codebuddy.ai/... and are unrelated to the protocol:

Token	Source
codebuddy.ai/docs	keybinding-template.ts:18,52, mcp-approval-box.tsx:16
codebuddy.ai/schemas	keybinding-template.ts:17,51
codebuddy.ai/login	chat-ui/src/browser/login/login.tsx:149
codebuddy.ai/agents	agent-ui/src/utils/workbuddy-share-origin.spec.ts:312
codebuddy.ai/profile	use-error-banner.tsx:186 (.../profile/plan)
codebuddy.ai/v2	model-provider.spec.ts:454,520 (API baseURL)

6. Rules for Third-Party ACP Clients

1. Do not produce any codebuddy.ai/* _meta key for identity or admission. The keys marked "Private" in §3.1 are issued by CodeBuddy's internal composition roots; client-fabricated ones will only be rejected (envelope validation, digest comparison, fencing all fail).
2. You can safely read all "Public" keys and optionally ignore them. They are all optional incremental information; semantic changes will not break the basic ACP flow.
3. Correlation IDs optionally carried on session/prompt (requestId / messageId / messageRequestId / userMessageId / promptRequestId / clientRequestId / sendTime / traceparent) are the only group recommended for client-side production — they only affect instrumentation and tracing, and do not participate in any authentication decisions.
4. _codebuddy.ai/* extension methods: the 9 marked "Private" in §4 (admitControl + three runtime*CredentialUpdate
   • completion trio + dispose duo) only appear in WorkBuddy's internal channels; standard surface calls will be rejected.

7. Related Documentation

• ACP Protocol Integration — --acp startup, Zed configuration, protocol features
• Zero _meta standing e2e: src/e2e/acp-zero-meta-contract.spec.ts
• Admission contract implementation: src/node/session/runtime-admission-acp-adapter.ts, src/node/session/process-login-acp-admission-service.ts, src/node/session/multi-owner-acp-admission-service.ts
• Profile registry: packages/runtime-admission-protocol/src/runtime-admission-contract.ts