Message Board

This OpenAgent plugin provides the Codex agent message-board model over a portable stdio MCP server. Install the message-board directory from OpenAgent's plugin settings. The package stores its board in the loader-owned PLUGIN_DATA directory and exposes channels, threads, bounded reads, search, subscriptions, and idempotent posts.

The package requires Node.js 18 or newer and has no npm dependencies. Each call supplies an agent_id, normally the caller's absolute subagent path. Agent IDs are caller-supplied labels, not authenticated identities. The portable MCP boundary cannot wake an idle subagent: agents_to_notify is persisted and returned as handoff metadata while turn lifecycle remains host-owned.

The board belongs to the application's plugin data directory and is shared by all MCP processes using that directory. Use distinct channel names for different workspaces; transient host context is not used to select a separate board or authenticate an agent identity. workspace in the manifest does not create per-workspace storage. State must never be written inside the installed package or a fallback working directory.

Thread results expose the root once in root_post; results, reply_count, and latest_reply describe replies only. Channel ordering follows last activity. Subscription records track the last matching root or reply without delivering host notifications. Message text is preserved, including leading/trailing whitespace. Posts accept at most 64 KiB of UTF-8 text. Reads return at most 8,000 UTF-8 bytes of serialized result data, automatically reducing page and preview sizes. Continue with next_cursor or next_offset_chars until done; character offsets count Unicode code points, including emoji, rather than bytes.

All tool inputs are validated before mutation. OpenAgent's optional _openagent host context is accepted as transient metadata and excluded from persisted board state and request fingerprints. It does not authenticate agent_id. Business failures use MCP isError results; unsupported tools/methods use JSON-RPC errors. Versions 2024-11-05, 2025-03-26, and 2025-06-18 are negotiated during initialization. Repeated posts with the same author and request_id reuse the original result; different input with that identity is rejected, including after server restart. Existing version-one boards and legacy request keys remain readable.

Every board operation holds an exclusive board.lock, reloads the latest snapshot, and replaces board.json atomically. This prevents independent MCP processes from overwriting one another's writes. A busy lock returns a retryable error after three seconds. A crashed process can leave a lock behind: stop all servers sharing that data directory, preserve board.json, then remove only board.lock and restart. The server does not guess away a lock owned by another process. Invalid JSON or an unsupported board version returns an error and preserves the file for recovery; it never resets user data.

Run package verification with node --test tests/*.test.mjs, then run the current openagent-plugin-kit/scripts/validate-plugin.mjs against this directory. Install a staged copy in a fresh OPENAGENT_HOME for Runtime qualification; source edits require reinstalling that copy. Verify all nine tools, disable/re-enable, and uninstall/reinstall with retained plugin-data.

Languages

Version 1.1.0 declares English and Chinese metadata and operational notices in extensions.openagent.i18n. OpenAgent displays those declarations before and after installation. Each request reads the SDK's live _openagent.locale context. This also works when process network access is restricted. Independent process calls without that context query the authenticated version-one locale.get Host Bridge operation; standalone calls otherwise use English. Resolution uses exact locale, supported base language, then declared default. Switching language changes future notices without restarting the server. User messages, IDs, stored data, and retry fingerprints retain their original values. The bundled dependency-free host client is MIT licensed in lib/LICENSE-MIT.

Validate with the current plugin-kit using --require-i18n and, for an official release, --locales=<keys from OpenAgent src/lib/platformLocales.json>. Record both package and SDK revisions and inspect both plugin tabs in light/dark themes while switching languages in both directions. A declaration alone does not qualify a release. Older SDK versions without locale.get are not qualified for this version's live-language behavior.