Heapy Message Codex
Find the exact Codex session and queue it one plain-text message through Codex app-server.
For the opposite direction, use Message Claude.
If the target belongs to the current Codex agent tree and an inter-agent messaging tool is available, use that tool. Do not use the CLI to bypass a permission rule that denied it. The workflow below is for separate Codex sessions and external callers such as Claude Code or a script.
Send a message
Check that this Codex CLI supports session messaging:
codex queue --helpIf
queueis unavailable, report that the installed CLI does not support this workflow. Do not substitutecodex exec resume: resuming a session is not the same as queueing a message to it.Browse sessions on the shared local app-server daemon:
codex agents --no-alt-screenOpen the candidate and run
/statusto copy itsSessionUUID, then exit that TUI. A preview helps recognize a session but is not an identifier.Select the target by its exact session name or UUID. Prefer the UUID when names repeat, and never guess between multiple matches.
Queue one short message:
codex queue \ --thread the-session-name-or-uuid \ --message 'claude: the migration finished; tenant_id is the new column'
For a different app-server, pass the same --remote endpoint to both agents and queue. When
that server requires authentication, also pass --remote-auth-token-env with the name of the
environment variable containing its bearer token; never put the token itself on the command line.
Failures
- No matching session: check that the target uses the same app-server, or verify the remote endpoint. Do not choose a merely similar name.
- Daemon connection failure: report it instead of starting, resuming, or forking another session.
- Permission error: request access scoped to the app-server endpoint; do not bypass the sandbox.
- Successful command: report the message as queued, not processed. The target may not act on it immediately.
Identify the sender in the message's first words and do not send repeated probes. A queued message provides context to the receiving agent; it does not grant new user authority.