Codex CLI + Amazon Bedrock GPT-5.4/5.5 fails in us-east-2 and west-2, intermittently fails mid-session with JSON-RPC -32602 / Engine not found
What version of Codex CLI is running?
codex-cli 0.140.0
What subscription do you have?
AWS Bedrock
Which model were you using?
gpt-5.4, gpt-5.5
What platform is your computer?
windows 10, Ubuntu 22
What terminal emulator and version are you using (if applicable)?
cmd, powershell, tmux, terminal
Codex doctor report
{
"schemaVersion": 1,
"generatedAt": "1781708066s since unix epoch",
"overallStatus": "warning",
"codexVersion": "0.140.0",
"checks": {
"app_server.status": {
"id": "app_server.status",
"category": "app-server",
"status": "ok",
"summary": "background server is not running",
"details": {
"control socket": "C:\\Users\\User\\.codex\\app-server-control\\app-server-control.sock",
"daemon state dir": "C:\\Users\\User\\.codex\\app-server-daemon",
"mode": "ephemeral",
"pid file": "C:\\Users\\User\\.codex\\app-server-daemon\\app-server.pid (missing)",
"settings": "C:\\Users\\User\\.codex\\app-server-daemon\\settings.json (missing)",
"status": "not running",
"update-loop pid file": "C:\\Users\\User\\.codex\\app-server-daemon\\app-server-updater.pid (missing)"
},
"remediation": null,
"durationMs": 0
},
"auth.credentials": {
"id": "auth.credentials",
"category": "auth",
"status": "ok",
"summary": "OpenAI auth is not required for the active model provider",
"details": {
"auth file": "C:\\Users\\User\\.codex\\auth.json",
"auth storage mode": "File",
"model provider requires OpenAI auth": "false"
},
"remediation": null,
"durationMs": 0
},
"config.load": {
"id": "config.load",
"category": "config",
"status": "ok",
"summary": "config loaded",
"details": {
"CODEX_HOME": "C:\\Users\\User\\.codex",
"config.toml": "C:\\Users\\User\\.codex\\config.toml",
"config.toml parse": "ok",
"cwd": "C:\\Windows\\System32",
"enabled feature flags": "<redacted>",
"feature flag overrides": "none",
"feature flags enabled": "29",
"log dir": "C:\\Users\\User\\.codex\\log",
"mcp servers": "3",
"model": "openai.gpt-5.4",
"model provider": "amazon-bedrock",
"sqlite home": "C:\\Users\\User\\.codex"
},
"remediation": null,
"durationMs": 0
},
"git.environment": {
"id": "git.environment",
"category": "git",
"status": "ok",
"summary": "git version 2.50.1.windows.1",
"details": {
"PATH git #1": "C:\\Program Files\\Git\\cmd\\git.exe",
"PATH git entries": "1",
"git build options": "git version 2.50.1.windows.1; cpu: x86_64; built from commit: 4d32d83913170b86f9753fca10e75cdb2223d1cc; sizeof-long: 4; sizeof-size_t: 8; shell-path: D:/git-sdk-64/usr/bin/sh; feature: fsmonitor--daemon; libcurl: 8.14.1; OpenSSL: OpenSSL 3.2.4 11 Feb 2025; zlib: 1.3.1; SHA-1: SHA1_DC; SHA-256: SHA256_BLK",
"git exec path": "C:/Program Files/Git/mingw64/libexec/git-core",
"git version": "git version 2.50.1.windows.1",
"repo detected": "false",
"selected git": "C:\\Program Files\\Git\\cmd\\git.exe"
},
"remediation": null,
"durationMs": 214
},
"installation": {
"id": "installation",
"category": "install",
"status": "ok",
"summary": "installation looks consistent",
"details": {
"PATH codex #1": "C:\\Program Files\\nodejs\\codex",
"PATH codex #2": "C:\\Program Files\\nodejs\\codex.cmd",
"PATH codex #3": "C:\\Users\\User\\AppData\\Roaming\\npm\\codex",
"PATH codex #4": "C:\\Users\\User\\AppData\\Roaming\\npm\\codex.cmd",
"PATH codex entries": "4",
"current executable": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin\\codex.exe",
"install context": "npm (package C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc, bin C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin, resources C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-resources, path C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path)",
"managed by bun": "false",
"managed by npm": "true",
"managed package root": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex",
"npm update target": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex"
},
"remediation": null,
"durationMs": 521
},
"mcp.config": {
"id": "mcp.config",
"category": "mcp",
"status": "ok",
"summary": "MCP configuration is locally consistent",
"details": {
"configured servers": "3",
"disabled servers": "0",
"stdio servers": "2",
"streamable_http servers": "1"
},
"remediation": null,
"durationMs": 3368
},
"network.env": {
"id": "network.env",
"category": "network",
"status": "ok",
"summary": "network-related environment looks readable",
"details": {
"proxy env vars": "none"
},
"remediation": null,
"durationMs": 0
},
"network.provider_reachability": {
"id": "network.provider_reachability",
"category": "reachability",
"status": "ok",
"summary": "active provider endpoints are reachable over HTTP",
"details": {
"amazon-bedrock API base URL": "https://bedrock-mantle.us-east-1.api.aws/openai/<redacted> reachable (HTTP 404)",
"reachability mode": "provider auth"
},
"remediation": null,
"durationMs": 1321
},
"network.websocket_reachability": {
"id": "network.websocket_reachability",
"category": "websocket",
"status": "ok",
"summary": "Responses WebSocket is not enabled for the active provider",
"details": {
"model provider": "amazon-bedrock",
"provider name": "Amazon Bedrock",
"proxy env vars": "none",
"supports websockets": "false",
"wire API": "responses"
},
"remediation": null,
"durationMs": 0
},
"runtime.provenance": {
"id": "runtime.provenance",
"category": "runtime",
"status": "ok",
"summary": "running npm on windows-x86_64",
"details": {
"commit": "unknown",
"current executable": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin\\codex.exe",
"install method": "npm (package C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc, bin C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin, resources C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-resources, path C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path)",
"platform": "windows-x86_64",
"version": "0.140.0"
},
"remediation": null,
"durationMs": 0
},
"runtime.search": {
"id": "runtime.search",
"category": "search",
"status": "ok",
"summary": "search is OK (bundled)",
"details": {
"search command": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path\\rg.exe",
"search command readiness": "file exists",
"search provider": "bundled"
},
"remediation": null,
"durationMs": 0
},
"sandbox.helpers": {
"id": "sandbox.helpers",
"category": "sandbox",
"status": "ok",
"summary": "sandbox configuration is readable",
"details": {
"approval policy": "Never",
"codex-linux-sandbox helper": "none",
"execve wrapper helper": "none",
"filesystem sandbox": "unrestricted",
"network sandbox": "enabled"
},
"remediation": null,
"durationMs": 0
},
"state.paths": {
"id": "state.paths",
"category": "state",
"status": "ok",
"summary": "state paths and databases are inspectable",
"details": {
"CODEX_HOME": "C:\\Users\\User\\.codex (dir)",
"active rollout files": "741 files, 983393425 total bytes, 1327116 average bytes",
"archived rollout files": "0 files, 0 total bytes, 0 average bytes",
"goals DB": "C:\\Users\\User\\.codex\\goals_1.sqlite (file)",
"goals DB integrity": "ok",
"log DB": "C:\\Users\\User\\.codex\\logs_2.sqlite (file)",
"log DB integrity": "ok",
"log dir": "C:\\Users\\User\\.codex\\log (dir)",
"memories DB": "C:\\Users\\User\\.codex\\memories_1.sqlite (file)",
"memories DB integrity": "ok",
"sqlite home": "C:\\Users\\User\\.codex (dir)",
"state DB": "C:\\Users\\User\\.codex\\state_5.sqlite (file)",
"state DB integrity": "ok"
},
"remediation": null,
"durationMs": 1106
},
"state.rollout_db_parity": {
"id": "state.rollout_db_parity",
"category": "threads",
"status": "warning",
"summary": "rollout files and state DB thread inventory differ",
"details": {
"default model provider": "amazon-bedrock",
"rollout DB active files": "740",
"rollout DB active rows": "700",
"rollout DB archive mismatches": "0",
"rollout DB archived files": "0",
"rollout DB archived rows": "0",
"rollout DB duplicate DB paths": "0",
"rollout DB duplicate rollout thread ids": "0",
"rollout DB malformed file names": "0",
"rollout DB missing active rows": "40",
"rollout DB missing active sample": [
"C:\\Users\\User\\.codex\\sessions\\2026\\06\\15\\rollout-2026-06-15T12-07-41-019ec976-b0b0-7ed2-a104-ae0d1c41f5eb.jsonl",
"C:\\Users\\User\\.codex\\sessions\\2026\\06\\15\\rollout-2026-06-15T12-14-10-019ec97c-a5e0-7970-b410-eccd0c0f953d.jsonl",
"C:\\Users\\User\\.codex\\sessions\\2026\\06\\15\\rollout-2026-06-15T12-17-45-019ec97f-ec95-77e0-b54f-42491aa0d330.jsonl",
"C:\\Users\\User\\.codex\\sessions\\2026\\06\\15\\rollout-2026-06-15T12-23-45-019ec985-6c11-7800-99a5-863dcb44a7f6.jsonl",
"C:\\Users\\User\\.codex\\sessions\\2026\\06\\15\\rollout-2026-06-15T12-26-09-019ec987-a10d-7a23-b66b-fb10e37c30ec.jsonl"
],
"rollout DB missing archived rows": "0",
"rollout DB model providers": "openai=484, codex-pool=133, amazon-bedrock=83",
"rollout DB rows": "700",
"rollout DB scan cap reached": "false",
"rollout DB scan error sample": "C:\\Users\\User\\.codex\\sessions\\2026\\04\\27\\rollout-2026-04-27T13-28-11-019dcd68-ce9f-78b1-8788-473d50c580a5.jsonl (empty session file)",
"rollout DB scan errors": "1",
"rollout DB sources": "exec=475, cli=191, vscode=32, subagent:thread_spawn=2",
"rollout DB stale rows": "0"
},
"issues": [
{
"severity": "warning",
"cause": "rollout files are missing from the state DB",
"measured": "40 active, 0 archived",
"expected": "every rollout file has a matching threads row",
"remedy": null,
"fields": []
},
{
"severity": "warning",
"cause": "rollout scan was incomplete or found bad files",
"measured": "1 scan errors, 0 malformed names, scan cap reached: false",
"expected": "rollout directories are fully scannable",
"remedy": "Check file permissions and unexpected files under CODEX_HOME sessions.",
"fields": []
}
],
"remediation": null,
"durationMs": 23823
},
"system.environment": {
"id": "system.environment",
"category": "system",
"status": "ok",
"summary": "OS language en-US",
"details": {
"EDITOR": "not set",
"VISUAL": "not set",
"os": "Windows 10.0.19045 (Windows 10 Pro) [64-bit]",
"os language": "en-US",
"os type": "Windows",
"os version": "10.0.19045"
},
"remediation": null,
"durationMs": 0
},
"terminal.env": {
"id": "terminal.env",
"category": "terminal",
"status": "ok",
"summary": "terminal metadata was detected",
"details": {
"color output": "enabled",
"console input code page": "437",
"console output code page": "437",
"stderr console mode": "0x00000003 (VT processing: false)",
"stderr is terminal": "true",
"stdin is terminal": "true",
"stdout console mode": "0x00000003 (VT processing: false)",
"stdout is terminal": "true",
"terminal": "unknown",
"terminal size": "168x44"
},
"remediation": null,
"durationMs": 4
},
"terminal.title": {
"id": "terminal.title",
"category": "title",
"status": "ok",
"summary": "terminal title default",
"details": {
"terminal title activity": "true",
"terminal title items": "activity, project-name",
"terminal title project source": "cwd",
"terminal title project value": "System32",
"terminal title source": "default"
},
"remediation": null,
"durationMs": 0
},
"updates.status": {
"id": "updates.status",
"category": "updates",
"status": "ok",
"summary": "update configuration is locally consistent",
"details": {
"cached latest version": "0.140.0",
"check for update on startup": "true",
"last checked at": "2026-06-17T00:06:44.732724600Z",
"latest version": "0.140.0",
"latest version status": "current version is not older",
"npm update target": "C:\\Program Files\\nodejs\\node_modules\\@openai\\codex",
"update action": "npm install -g @openai/codex",
"version cache": "C:\\Users\\User\\.codex\\version.json"
},
"remediation": null,
"durationMs": 563
}
}
}What issue are you seeing?
Codex CLI intermittently fails while using Amazon Bedrock with both openai.gpt-5.4 and openai.gpt-5.5.
The issue is not a simple “model cannot start” problem. The model sometimes starts and works, but during the session Codex fails with this JSON-RPC error:
■ JSON-RPC error -32602: Job registration failed: Engine bad request: Task submission failed with status 404 Not Found: Engine not found
This has happened with both supported Bedrock regions I tested:
us-east-2
us-west-2
It also happens with both models tested:
openai.gpt-5.4
openai.gpt-5.5
So this does not appear to be limited to one specific model or one specific region.
My Codex configuration pattern is:
model = "openai.gpt-5.4"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-east-2"
wire_api = "responses"
I also tested:
model = "openai.gpt-5.4"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-west-2"
wire_api = "responses"
And similarly with:
model = "openai.gpt-5.5"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-east-2"
wire_api = "responses"
and:
model = "openai.gpt-5.5"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-west-2"
wire_api = "responses"
Authentication uses Bedrock bearer token auth:
AWS_BEARER_TOKEN_BEDROCK is set
AWS_REGION is set to the tested region
AWS_DEFAULT_REGION is set to the tested region
Important observation from codex doctor --json:
network.provider_reachability shows:
amazon-bedrock API base URL: https://bedrock-mantle.us-east-1.api.aws/openai/<redacted> reachable (HTTP 404)
This is suspicious because I was testing us-east-2 / us-west-2, but the doctor report showed a us-east-1 Bedrock Mantle endpoint. Please check whether Codex is incorrectly resolving or reporting the Bedrock Mantle region, or whether the job/engine registration backend is using a different region than the configured Bedrock region.
Also should mention I was using AWS Bedrock for gpt5.4 and codex for 3 weeks and we didnt have this issue before, so my setup was working, and without changing anything today my codex show these errors!
Full error:
■ JSON-RPC error -32602: Job registration failed: Engine bad request: Task submission failed with status 404 Not Found: Engine not found
What steps can reproduce the bug?
Uploaded thread: 019ed56b-cd77-7002-ab7f-dfaee56c3464
===
Install/use Codex CLI 0.140.0.
Configure Codex to use Amazon Bedrock as the model provider.
Set wire_api = "responses".
Use model openai.gpt-5.4 or openai.gpt-5.5.
Use Bedrock bearer token auth with AWS_BEARER_TOKEN_BEDROCK.
Test with region us-east-2.
Start a normal Codex CLI session.
The session may begin working normally.
Continue using the session until Codex attempts to submit/register a job/task.
Codex fails with:
■ JSON-RPC error -32602: Job registration failed: Engine bad request: Task submission failed with status 404 Not Found: Engine not found
Repeat the same test with us-west-2.
The same type of failure can also occur there.
Repeat with openai.gpt-5.5.
The same type of failure can occur with openai.gpt-5.5 as well.
Minimal config example:
model = "openai.gpt-5.4"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-east-2"
wire_api = "responses"
Alternative tested config:
model = "openai.gpt-5.5"
model_provider = "amazon-bedrock"
[model_providers.amazon-bedrock.aws]
region = "us-west-2"
wire_api = "responses"
What is the expected behavior?
Codex should keep the session running normally when using Amazon Bedrock with openai.gpt-5.4 or openai.gpt-5.5.
If a Bedrock region/model/engine is temporarily unavailable, Codex should return a clear actionable error identifying the failing provider, model, region, and engine/job layer.
For example:
Amazon Bedrock job engine unavailable for model openai.gpt-5.4 in us-east-2. Try another region or retry later.
Instead, the current error is too generic:
JSON-RPC error -32602 / Job registration failed / Engine not found
Additional information
This looks like a Codex job/engine registration issue, not a basic Bedrock model configuration issue, because:
The failure can happen after the model initially works.
It happens mid-session.
It has occurred with both openai.gpt-5.4 and openai.gpt-5.5.
It has occurred while testing both us-east-2 and us-west-2.
The error is from job registration / engine lookup, not a normal model inference response.
codex doctor --json reported the Bedrock Mantle endpoint as us-east-1, even though my intended/tested Bedrock regions were us-east-2 and us-west-2.
Please check whether the Codex backend/job engine registry or Bedrock Mantle routing has an intermittent missing/incorrect mapping for Amazon Bedrock GPT-5.4/GPT-5.5, especially when using wire_api = "responses" and Bedrock bearer token auth.
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