I’m posting this here primarily to raise visibility around what appears to be a current Codex Desktop regression affecting inter-task / cross-thread workflows.
For at least the past week, the effectful inter-task tools I rely on for multi-agent workflows have effectively stopped working.
The previous inter-task tooling now reports that it is no longer available through dynamic tools and directs Codex to use the codex_app MCP server instead.
“codex_app__create_thread” is advertised but fails with “no longer available through dynamic tools”
However, the corresponding replacement functionality does not appear to actually be exposed.
In particular, tools needed for inter-task actions such as:
-
send_message_to_thread -
create_thread -
handoff_thread
are unavailable, while read-oriented tools such as list_threads, read_thread, and wait_threads may still be present.
This leaves Codex in a contradictory state where its environment/instructions point toward a replacement codex_app MCP mechanism, but the effectful replacement tools needed to actually perform those workflows are not available.
The canonical GitHub report is openai/codex issue #40865.
I independently opened another GitHub issue after reproducing the same failure, but closed it after determining that #40865 already covered the underlying regression.
This is particularly disruptive for users relying on Codex Desktop for multi-task or multi-agent workflows. In my case, cross-task communication is a core part of how I use Codex, so this regression has effectively broken that workflow rather than simply degrading it.
I’ve also seen other recent reports involving instability around codex_app, thread tooling, and agent/task communication, which makes me concerned that this may be part of a broader regression in the Desktop inter-task tooling layer.
I’ve already reported related Codex Desktop problems through GitHub and contacted support, but I have not been able to get any response or indication that this particular regression is being investigated.
Posting here in the hope that this reaches someone on the Codex/Desktop team who can confirm:
-
Whether removal of the old dynamic inter-task tools was intentional.
-
Whether
codex_appis intended to provide replacements forsend_message_to_thread,create_thread, and related tools. -
Whether the fact that those replacement tools are currently unavailable is a known regression.
If anyone else is seeing the same behavior, please add your reproduction details here or to GitHub issue #40865.
Environment context: I’m using Codex Desktop on macOS with tasks that frequently run against remote/dev-container environments backed by Docker. I have reproduced the inter-task tooling failure across both existing and newly created tasks, so this does not appear to be limited to a single stale thread or container state. The affected capability is the Desktop inter-task/tooling layer itself rather than normal command execution inside the remote container.