Constant "Bad Request" happening to me

Based on the logs, I'm guessing that you've enabled a feature that is still under development and is not yet supported. Please review your config.toml.

Would background terminal be one of those?

Try renaming your config.toml file temporarily, then relaunch Codex and log in. Do you still see the "Bad Request" in that case?

Yes. 019c200d-be63-7152-aa8b-2b084f20432a

Sorry, I haven't been doing dev on the machine that was giving me these problems, will try again when I get a chance.

This is no longer reproducing for me, sorry.

I am currently having this all the time. Every second request gets me a red {"detail":"Bad Request"} even requests that are rather short and do not require lots of tokens (as it looks to me at least). I cannot let codex run unattended for more than a few minutes just to come back at it stopped mid-flight.

I am exclusively using codex 5.3 with xhigh thinking with my Pro account. I also told it to avoid parsing/sending large results but it happens at random times.

here is my config

model = "gpt-5.3-codex"
model_reasoning_effort = "xhigh"

approval_policy = "never"
sandbox_mode = "danger-full-access"
sandbox_workspace_write.network_access = true
web_search = "live"
features.shell_snapshot = true
features.unified_exec = true
features.steer = true
features.collab = true
model_verbosity = "high"
history.persistence = "save-all"
suppress_unstable_features_warning = true
personality = "pragmatic"

# [mcp_servers.gabs]
# command = "gabs"
# args = ["server"]

[projects."/Users/ap"]
trust_level = "trusted"

[notice]
hide_gpt5_1_migration_prompt = true
"hide_gpt-5.1-codex-max_migration_prompt" = true

[notice.model_migrations]
"gpt-5.2" = "gpt-5.2-codex"

@pardeike, when you see this happen, please use the /feedback command to upload your logs and session details, then post the thread ID here.

Edit: Sorry, I just saw your post in #10571. Thanks for uploading your details.