chattolib/AGENTS.md

AGENTS.md

Guidance for AI coding assistants (Claude Code, Cursor, Aider, etc.) working in this repository. Human contributors are welcome to use it too.

IMPORTANT: before you do anything else, run the beans prime command and heed its output. Tasks for this project are tracked in .beans/ via the beans CLI.

Runbooks

• Releasing a new chattolib version tracking a Chatto server release — docs/upgrade-chatto.md. Regenerates protos, adapts the client for wire changes, bumps the version, verifies, commits, pushes to both remotes, builds, and publishes to PyPI.

Project Overview

chattolib is an async Python client library for the Chatto webchat Connect API (https://chat.chatto.run/api/connect/…). Chatto migrated from GraphQL to protobuf-first ConnectRPC in v0.4.x (see ADR-042, which supersedes ADR-003). This library speaks Connect JSON over HTTP for all request/response operations.

Versioning

chattolib's version tracks the Chatto server version it targets. A new Chatto release triggers a matching chattolib release (e.g. Chatto 0.4.2 → chattolib 0.4.2). If a chattolib-only fix is needed between server releases, use a post-release suffix (0.4.2.post1) rather than bumping the base number ahead of Chatto.

Build & Development

# Install in development mode
pip install -e ".[dev]"

# Run all tests (mocked)
pytest tests/test_client.py

# Run integration tests (require CHATTO_LOGIN / CHATTO_PASSWORD)
pytest tests/test_integration.py -v

# Lint & format
ruff check .
ruff format .

# Type checking
mypy src/chattolib

Architecture

The library uses the official connectrpc Python package for the request/response API surface: _transport.build_service_clients(base_url) instantiates one ConnectRPC service client per Chatto service, all sharing the same address and the google.protobuf binary codec. Realtime events use a separate binary-protobuf WebSocket protocol (chatto.realtime.v1) served at /api/realtime, implemented in realtime.py on top of websockets and generated protobuf bindings.

Package layout: src/chattolib/

• client.py — ChattoClient async class. Each method builds a protobuf request, invokes the appropriate generated service stub via _rpc, and normalises the response into the library's dataclass types. services is a public escape hatch for reaching the raw ConnectRPC service clients directly.
• _transport.py — instantiates the ConnectRPC service clients, translates connectrpc.errors.ConnectError into ChattoConnectError/ChattoAuthError, and exposes pb_to_dict(message) for the request/response ↔ dataclass bridge.
• types.py — Dataclasses and StrEnum types mirroring the protobuf messages, with .parse(dict) classmethods that consume Connect JSON.
• exceptions.py — ChattoError, ChattoConnectError (wraps Connect protocol errors), ChattoAuthError.
• realtime.py — Protobuf realtime WebSocket client. stream_events(client) yields RealtimeEvent(kind, payload, ...) values. Errors surface as ChattoRealtimeError / ChattoRealtimeCloseError.
• _pb/ — Vendored, generated Python protobuf message classes (*_pb2.py) and ConnectRPC service stubs (*_connect.py) for every Chatto service. Regenerate with scripts/generate_pb.sh (needs protoc and protoc-gen-connect-python on PATH). The script fetches the .proto sources from chattocorp/chatto and rewrites the bindings. The _pb/__init__.py inserts its own directory onto sys.path so the generated from chatto.api.v1 import ... imports resolve without polluting the top-level namespace of dependent projects.

Connect protocol conventions

• Endpoint: POST https://<host>/api/connect/<fully.qualified.Service>/<Method> with a JSON body.
• Empty request messages send {}.
• Field names on the wire are camelCase (proto → JSON mapping). Python dataclass fields are snake_case.
• Enums on the wire are the full enum value name as a string, e.g. "PRESENCE_STATUS_ONLINE". types._parse_enum also accepts the short tail ("ONLINE") for robustness.
• Timestamps are RFC 3339 strings (usually Z-suffixed). Use types.parse_datetime / types.format_datetime helpers.
• optional scalars: absent from JSON when unset. A present empty string is distinct.
• bytes: base64-encoded strings (used by UserService.UploadAvatar via the ImageUpload message).
• Errors: non-2xx HTTP status with a JSON body of {"code": "...", "message": "...", "details": [...]}. ChattoConnectError surfaces code, message, status_code, details.

Auth

chattolib is a bot library. Bots authenticate with a key (e.g. cht_BK_...) used directly as a bearer token — there is no password login and no /auth/login round-trip. Construct a client with ChattoClient(token="cht_BK_..."), or use the higher-level Bot.login(key, base_url=…) facade (see bot.py). A bot is just a User with is_bot=true plus a set of capability grants; the Connect API enforces permissions per call, so a bot can invoke the same RPCs a human can, subject to its grants.

Key services exposed by the client

Domain	Service (chatto.api.v1.… unless noted)	Notable RPCs
Discovery	chatto.discovery.v1.ServerDiscoveryService	GetServer (public), ListNeighbors (public), ListNeighborhoodServers (public — the Neighborhood the server discovered in the background; NeighborhoodServer { origin, profile, direct_neighbor, recommended_by_origins } + refreshed_at)
Server	ServerService	GetMotd, GetRuntimeConfig
Viewer	ViewerService	GetViewer
My account	MyAccountService	UpdateSettings, SetPresence (legacy live report), GetPresencePreference, SetPresencePreference, RefreshPresence, SetCustomStatus, DeleteCustomStatus, ChangePassword, DeleteMyAccount (avatar upload was removed in 0.5.0b4; UpdateProfile moved to UserService in 0.5.0b9)
User profiles	UserService	UpdateUserProfile (self or privileged — the single profile-edit RPC since 0.5.0b9; display_name/login/bio + inferred update_mask), ListUsers/GetUser/BatchGetUsers (directory), UploadAvatar/DeleteAvatar
Roles	RoleService	ListRoles, GetRole, BatchGetRoles
Room directory	RoomDirectoryService	ListRooms, ListRoomGroups, GetRoomGroup, BatchGetRoomGroups, GetRoom, BatchGetRooms
Rooms	RoomService	CreateRoom, UpdateRoom, ArchiveRoom, UnarchiveRoom, JoinRoom, JoinRoomGroup, StartDM, LeaveRoom, AddMember, RemoveMember, ListMembers, GetMember, BatchGetMembers, RemoveUser, LiftSuspension, ListSuspensions, RefreshTypingIndicator, GetRoomEvents, GetRoomEventsAround, MarkRoomAsRead, ListRoomAttachments
Messages	MessageService	FetchLinkPreview, CreateMessage, UpdateMessage, DeleteMessage, DeleteAttachment, DeleteLinkPreview, GetMessage, BatchGetMessages, AddReaction, RemoveReaction
Threads	ThreadService	FollowThread, UnfollowThread, ListFollowedThreads (unread_only filters to threads with unread replies, since 0.5.0b8), GetThreadEvents, GetThreadEventsAround, MarkThreadAsRead
Notifications	NotificationService	ListNotifications, GetNotification, BatchGetNotifications, ListRoomNotifications, ListRoomNotificationCounts, HasNotifications, DismissNotification, DismissAllNotifications
Notification prefs	NotificationPreferencesService	Get/Update × Server/Room
Notification policy	NotificationPolicyService	GetNotificationPolicy, BatchGetNotificationPolicies, UpdateNotificationPolicy — all scoped (server / room group / room) via NotificationPolicyScope
Permissions	PermissionService	ListEffectivePermissions (the resolved permission decisions for a user)
Push	PushNotificationService	Subscribe, Unsubscribe
Assets	AssetService	GetAsset, BatchGetAssets
Asset uploads	AssetUploadService	CreateUpload, UploadChunk, GetUpload, CompleteUpload, CancelUpload. upload_attachment(room, path) helper computes SHA-256, chunks, and completes in one call.
Admin: server	chatto.admin.v1.AdminServerService	GetServerConfig, UpdateServerConfig, UploadServerLogo, DeleteServerLogo, UploadServerBanner, DeleteServerBanner, GetServerSecurityConfig, UpdateBlockedUsernames
Admin: room layout	chatto.admin.v1.AdminRoomLayoutService	ListRoomGroups, Create/Update/Delete/ReorderRoomGroup(s), MoveRoomGroup, MoveRoomToGroup, ReorderSidebarItemsInGroup, MoveSidebarItem, Create/Update/Delete/MoveSidebarLink(ToGroup)
Admin: users	chatto.admin.v1.AdminUserService	ListMembers, GetMember, BatchGetMembers, AssignRole, RevokeRole, UpdateUserPassword, ClearUsernameCooldown, DeleteUser (the old UpdateUser admin RPC was removed in 0.5.0b9 — privileged profile edits go through UserService.UpdateUserProfile)
Admin: roles	chatto.admin.v1.AdminRoleService	ListRoles, GetRole, CreateRole, UpdateRole, DeleteRole, ReorderRoles
Admin: event log	chatto.admin.v1.AdminEventLogService	ListEvents, ListEventTypes, GetEvent (raw response)
Admin: diagnostics	chatto.admin.v1.AdminDiagnosticsService	GetSystemInfo (raw response; since 0.5.0b14 also carries a livekit AdminLiveKitStatus block — setup/config state, server-API reachability connection_state, webhook times; never secrets)
Admin: permissions	chatto.admin.v1.AdminPermissionService	GetRole/UserPermissionMatrix, ListRole/UserPermissionDecisions, ExplainPermissions, SetRolePermission, SetUserPermission (raw responses where the permission shape is server-version-dependent)
Voice calls	VoiceCallService	ListActiveCalls, GetActiveCall, BatchGetActiveCalls, JoinCall, LeaveCall, CreateCallToken
Realtime (WS)	chatto.realtime.v1 protobuf WS (protocol v4)	stream_events(client) / RealtimeConnection — the client sends one RealtimeSubscribe handshake; the server streams event (a 48-member oneof of thin, caller-scoped hints, incl. viewer_presence_preference_changed added in 0.5.0b6), snapshot, caught_up, heartbeat, and close (with a RealtimeCloseCode and retry_after)

Naming conventions

• Python method names: verb_noun style (create_room, post_message, mark_room_as_read); most method names mirror the Connect method with the service name dropped.
• Python field names: snake_case; wire JSON uses camelCase and parsers translate.
• Enum classes: PascalCase (PresenceStatus, RoomKind, NotificationLevel, TimeFormat, ImageFitMode, RoomDirectoryScope, VideoProcessingStatus). Their value is the full protobuf enum-name string (e.g. "ROOM_KIND_CHANNEL").
• Dataclasses: PascalCase matching the protobuf message names (Room, Message, Notification, RoomWithViewerState, etc.).

Gotchas from the migration

• The old RoomType enum is now RoomKind (ROOM_KIND_CHANNEL / ROOM_KIND_DM).
• Room no longer carries viewer-scoped state (hasUnread, etc.). The directory service returns RoomWithViewerState { room, viewerState } for that.
• PresenceStatus now includes UNSPECIFIED. SetPresence (was UpdatePresence) rejects both OFFLINE and UNSPECIFIED.
• TimeFormat values changed: HOUR_12 / HOUR_24 / AUTO (was TWELVE_HOUR / TWENTY_FOUR_HOUR).
• Notifications are strongly typed via a oneof (direct_message, mention, reply, room_message); Notification.kind carries the tag.
• Timeline events (RoomTimelineEvent) are also a oneof; TimelineEvent.kind names the case (message_posted, room_created, …). Only message_posted populates a Message payload.
• User.is_bot is gone; a user is a bot when it carries a bot (BotInfo { owner_user_id }) field. User.is_bot is now a derived @property.
• Avatar upload was removed in 0.5.0b4 — there is no UploadAvatar/ImageUpload and no upload_avatar/delete_avatar client methods anymore.
• Server profile fields are no longer inside server.profile; the shape is now ServerPublicProfile returned by ServerDiscoveryService.GetServer.
• No more motd on the public profile; it is a separate authenticated RPC (ServerService.GetMotd).
• Room groups can contain SidebarLink items (not just rooms). RoomGroup.sidebar_links exposes them.
• 0.5.0b6 split presence into a saved preference and a live report. SetPresence is now the legacy, transient live report (still rejects OFFLINE/UNSPECIFIED); a saved choice takes precedence over it, even a user_selected one. The new pair is GetPresencePreference/SetPresencePreference (choice for every device on the server; OFFLINE = "Appear Offline" and is allowed there; a stale expected_revision returns ABORTED) plus RefreshPresence for 30-second liveness. Message also gained viewer_state (MessageViewerState.can_reply_in_thread), resolved per viewer even before a thread exists.
• 0.5.0b7 replaced the room ban triad with a suspension triad (breaking). BanMember/UnbanMember/ListBans and the RoomBan message are gone; they are now RemoveUser (remove a member with a required reason; the optional oneof suspension is either suspension_expires_at or suspend_indefinitely — at most one, and Universal rooms require one; DM rooms are excluded), LiftSuspension (no-op success when no active suspension), and ListSuspensions (returns repeated RoomSuspension suspensions, page newest-first). The client methods are remove_user(...) / lift_suspension(...) / list_suspensions(...) and the dataclass is RoomSuspension (the ban's expires_at field name is kept). Both RemoveUser and LiftSuspension require room.remove-member at server scope.
• 0.5.0b8 added the public ServerDiscoveryService.ListNeighborhoodServers RPC (no session needed; the server caches background discovery, refreshed at least hourly). NeighborhoodServer.profile is a ServerPublicProfile without the welcome message, and its logo/banner URLs are server-relative paths of copies on the called server — resolve them against that server's origin, not the neighbor's. ListFollowedThreadsRequest.unread_only filters to followed threads with unread replies (older servers ignore the field and return everything; the page total then counts only the filtered set).
• 0.5.0b9 consolidated all public-profile edits into a new chatto.api.v1.UserService.UpdateUserProfile RPC (breaking for both edit paths). MyAccountService.UpdateProfile was removed and chatto.admin.v1.AdminUserService.UpdateUser was removed; the new RPC takes a required user_id plus display_name/login/bio (an inferred update_mask) and returns just the updated User — no admin member row. Self-updates need no extra authority; editing another human requires user.manage-accounts (and, for a bot target, ownership of the bot, user.manage-accounts, or bot.manage), and a user.manage-accounts caller bypasses the username-change cooldown without starting one. Client: new update_user_profile(user_id, ...) plus a self-service update_profile(...) that resolves the caller's id via the viewer snapshot and delegates (same public signature as before, plus bio); admin_update_user(...) keeps its name/shape but now delegates to the same RPC and its second return value is always None (the removed response no longer carries an AdminMember) — re-fetch with admin_get_member() when the row is needed. User.bio is now documented as Markdown. The vendored user_service.proto also newly carries ListUsers/GetUser/BatchGetUsers (directory) and UploadAvatar/DeleteAvatar, for which chattolib still ships no wrappers.
• 0.5.0b10: DM rooms keep deleted participants in member_user_ids. Since 0.5.0-beta.10, RoomWithViewerState.member_user_ids on a DM includes participants whose accounts were deleted (the directory no longer prunes them); clients render those as deleted users. Channel rooms still carry an empty list. The wire shape is unchanged (same field, same number) and RoomWithViewerState.parse already copies the full list — so no code change was needed, but code that resolves every member_user_ids entry to a User must tolerate users that get_user no longer returns.
• 0.5.0b14: pinning is gated by a dedicated message.pin permission (server-side behavior change; no wire change). RoomService.CreatePinnedMessage/DeletePinnedMessage required room.manage until 0.5.0-beta.13; since 0.5.0-beta.14 they require the new message.pin permission instead. The RPCs, their request/response messages, and chattolib's pin_message/unpin_message/list_pinned_messages wrappers are unchanged — but a bot/role that pinned via room.manage must now hold message.pin (or the server returns PERMISSION_DENIED). Same release added an additive livekit (AdminLiveKitStatus) field 6 to admin GetSystemInfoResponse (LiveKit setup/config state, server-API reachability as AdminLiveKitConnectionState, webhook receipt times; never the API/webhook secrets) — admin_get_system_info() returns it raw in data["livekit"] with no client change.
• Never regenerate protos from chattocorp/chatto@main. scripts/generate_pb.sh defaults to a tag derived from pyproject.toml: v<base> for finals, and v<base>-<kind>.<n> for PEP 440 pre-releases (0.5.0b6 → v0.5.0-beta.6), probing candidates with git ls-remote (exact ref match; the REST /tags/{name} endpoint 404s on lightweight tags). Override with CHATTO_REF=<tag> only when you know the deployed server has caught up. chattolib 0.4.19 shipped once from main and broke realtime for every downstream client because Chatto's main had a protocol-v2 rewrite that the deployed 0.4.19 server did not speak.
• 0.5.0b15.post1: the protoc plugin's _method_name is acronym-aware. The old splitter inserted _ before every capital, so StartDM generated start_d_m — while client.py called start_dm, making start_dm() an AttributeError at call time (shipped broken since the 0.5.x ConnectRPC regeneration; StartDM is the only RPC in the current proto set with an acronym run, so nothing else changed). Fixed in src/chattolib/_protoc_plugin.py (StartDM → start_dm; GetRoomDMStats → get_room_dm_stats); regenerate to pick it up. Note the server side: a bot key cannot call StartDM at all (PERMISSION_DENIED — DMs are human-initiated; a bot can only answer inside a DM room a human already opened), so the wrapper is kept for human-login-style use but is not exercised by bot integration tests. types._snake_case (the same bug class, used for timeline/notification kind names) was hardened the same way in 0.5.0b15.post2 — latent today: no oneof field in the current proto set has an acronym run, so its output is unchanged.

Known bugs

• Realtime is now protocol v4 — there are no projection frames. The v2/v3 "projection" frames (RealtimeProjectionEvent / per-op RealtimeProjectionOperation) no longer exist. Instead the client sends a single RealtimeSubscribe handshake and the server streams event frames (a 48-member oneof of thin, caller-scoped hints — identifiers, not full resources), plus snapshot (one initial state), caught_up (recovery-to-live boundary), heartbeat, and close (with a RealtimeCloseCode and retry_after). Live events carry IDs, so clients hydrate the referenced resource via the matching ConnectRPC (e.g. get_message) using the event's cursor. Bot._handle_live re-derives BotMessageEvent by hydrating the posted message. Since 0.5.0b6 the oneof has a 48th member, viewer_presence_preference_changed (an empty payload delivered only to the account whose own presence preference changed; Bot dispatches it as kind="presence_preference" and the new choice is read back via get_presence_preference).
• RealtimeClose.code is the enum RealtimeCloseCode (e.g. SESSION_TERMINATED, RESYNC_REQUIRED, UNSUPPORTED_PROTOCOL); chattolib.realtime maps it to its short name for ChattoRealtimeCloseError.code. A non-reconnect close (e.g. SESSION_TERMINATED) means the bot should stop, not reconnect.