Upwork MCP startup fails with "Unexpected response type" before tool discovery on Windows

[crain-ai-works]

What version of Codex CLI is running?

codex-cli 0.150.1

What subscription do you have?

ChatGPT Pro

Which model were you using?

gpt-5.6-sol, xhigh reasoning

What platform is your computer?

Microsoft Windows NT 10.0.19045.0 x64

What terminal emulator and version are you using (if applicable)?

Windows PowerShell 5.1.19041.7663 | Host: ConsoleHost 5.1.19041.7663

Codex doctor report

{
  "schemaVersion": 1,
  "generatedAt": "1787960228s since unix epoch",
  "overallStatus": "warning",
  "codexVersion": "0.150.1",
  "checks": {
    "app_server.status": {
      "id": "app_server.status",
      "category": "app-server",
      "status": "ok",
      "summary": "background server is not running",
      "details": {
        "control socket": "C:\\Users\\crain\\.codex\\app-server-control\\app-server-control.sock",
        "daemon state dir": "C:\\Users\\crain\\.codex\\app-server-daemon",
        "mode": "ephemeral",
        "pid file": "C:\\Users\\crain\\.codex\\app-server-daemon\\app-server.pid (missing)",
        "settings": "C:\\Users\\crain\\.codex\\app-server-daemon\\settings.json (missing)",
        "status": "not running",
        "update-loop pid file": "C:\\Users\\crain\\.codex\\app-server-daemon\\app-server-updater.pid (missing)"
      },
      "remediation": null,
      "durationMs": 0
    },
    "auth.credentials": {
      "id": "auth.credentials",
      "category": "auth",
      "status": "ok",
      "summary": "auth is configured",
      "details": {
        "auth file": "C:\\Users\\crain\\.codex\\auth.json",
        "auth storage mode": "File",
        "stored API key": "false",
        "stored ChatGPT tokens": "true",
        "stored agent identity": "false",
        "stored auth mode": "chatgpt"
      },
      "remediation": null,
      "durationMs": 0
    },
    "config.load": {
      "id": "config.load",
      "category": "config",
      "status": "ok",
      "summary": "config loaded",
      "details": {
        "CODEX_HOME": "C:\\Users\\crain\\.codex",
        "config.toml": "C:\\Users\\crain\\.codex\\config.toml",
        "config.toml parse": "ok",
        "cwd": "C:\\Users\\crain",
        "enabled feature flags": "<redacted>",
        "feature flag overrides": "none",
        "feature flags enabled": "46",
        "log dir": "C:\\Users\\crain\\.codex\\log",
        "mcp servers": "3",
        "model": "gpt-5.6-sol",
        "model provider": "openai",
        "sqlite home": "C:\\Users\\crain\\.codex"
      },
      "remediation": null,
      "durationMs": 0
    },
    "desktop.app.version": {
      "id": "desktop.app.version",
      "category": "desktop",
      "status": "ok",
      "summary": "the desktop application is installed",
      "details": {
        "log directory": "$HOME\\AppData\\Local\\Codex/Logs",
        "running": "true",
        "version": "26.825.3734.0"
      },
      "remediation": null,
      "durationMs": 0
    },
    "desktop.app_server.handshake": {
      "id": "desktop.app_server.handshake",
      "category": "desktop",
      "status": "ok",
      "summary": "the desktop app-server initialized successfully",
      "details": {},
      "remediation": null,
      "durationMs": 0
    },
    "desktop.security.enforcement": {
      "id": "desktop.security.enforcement",
      "category": "desktop",
      "status": "ok",
      "summary": "no locally visible recent Codex security enforcement was found",
      "details": {},
      "remediation": null,
      "durationMs": 0
    },
    "git.environment": {
      "id": "git.environment",
      "category": "git",
      "status": "ok",
      "summary": "git version 2.51.0.windows.2",
      "details": {
        "PATH git #1": "C:\\Program Files\\Git\\cmd\\git.exe",
        "PATH git entries": "1",
        "git build options": "git version 2.51.0.windows.2; cpu: x86_64; built from commit: ade1f1c136682d1bed178d573dc4dc40dca11623; sizeof-long: 4; sizeof-size_t: 8; shell-path: D:/git-sdk-64-build-installers/usr/bin/sh; feature: fsmonitor--daemon; libcurl: 8.16.0; OpenSSL: OpenSSL 3.5.3 16 Sep 2025; zlib: 1.3.1; SHA-1: SHA1_DC; SHA-256: SHA256_BLK; default-ref-format: files; default-hash: sha1",
        "git exec path": "C:/Program Files/Git/mingw64/libexec/git-core",
        "git version": "git version 2.51.0.windows.2",
        "repo detected": "false",
        "selected git": "C:\\Program Files\\Git\\cmd\\git.exe"
      },
      "remediation": null,
      "durationMs": 97
    },
    "git.worktree.dev_drive": {
      "id": "git.worktree.dev_drive",
      "category": "git",
      "status": "ok",
      "summary": "no Git worktree is active",
      "details": {},
      "remediation": null,
      "durationMs": 0
    },
    "installation": {
      "id": "installation",
      "category": "install",
      "status": "ok",
      "summary": "installation looks consistent",
      "details": {
        "PATH codex #1": "C:\\Users\\crain\\AppData\\Local\\Programs\\OpenAI\\Codex\\bin\\codex.exe",
        "current executable": "C:\\Users\\crain\\AppData\\Local\\Programs\\OpenAI\\Codex\\bin\\codex.exe",
        "install context": "standalone (windows, package C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc, bin C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\bin, resources C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\codex-resources, path C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\codex-path)",
        "managed by bun": "false",
        "managed by npm": "false",
        "managed by pnpm": "false",
        "managed package root": "not set"
      },
      "remediation": null,
      "durationMs": 81
    },
    "mcp.config": {
      "id": "mcp.config",
      "category": "mcp",
      "status": "ok",
      "summary": "MCP configuration is locally consistent",
      "details": {
        "configured servers": "3",
        "disabled servers": "1",
        "stdio servers": "2",
        "streamable_http servers": "1"
      },
      "remediation": null,
      "durationMs": 222
    },
    "network.env": {
      "id": "network.env",
      "category": "network",
      "status": "ok",
      "summary": "network-related environment looks readable",
      "details": {
        "managed proxy": "not configured",
        "proxy env vars": "none",
        "respect system proxy": "disabled"
      },
      "remediation": null,
      "durationMs": 0
    },
    "network.provider_reachability": {
      "id": "network.provider_reachability",
      "category": "reachability",
      "status": "ok",
      "summary": "active provider endpoints are reachable over HTTP",
      "details": {
        "ChatGPT inference URL": "https://chatgpt.com/backend-api/<redacted> reachable (HTTP 405)",
        "desktop assets CDN": "https://persistent.oaistatic.com/codex-app-prod/<redacted> reachable (HTTP 200)",
        "reachability mode": "ChatGPT auth"
      },
      "remediation": null,
      "durationMs": 176
    },
    "network.websocket_reachability": {
      "id": "network.websocket_reachability",
      "category": "websocket",
      "status": "ok",
      "summary": "Responses WebSocket handshake succeeded",
      "details": {
        "DNS": "2 IPv4, 2 IPv6, first IPv4",
        "auth mode": "chatgpt",
        "connect timeout": "15000 ms",
        "endpoint": "wss://chatgpt.com/backend-api/<redacted>",
        "handshake result": "HTTP 101 Switching Protocols",
        "model provider": "openai",
        "provider name": "OpenAI",
        "proxy env vars": "none",
        "reasoning header": "false",
        "server model present": "false",
        "supports websockets": "true",
        "wire API": "responses"
      },
      "remediation": null,
      "durationMs": 667
    },
    "runtime.provenance": {
      "id": "runtime.provenance",
      "category": "runtime",
      "status": "ok",
      "summary": "running standalone on windows-x86_64",
      "details": {
        "commit": "unknown",
        "current executable": "C:\\Users\\crain\\AppData\\Local\\Programs\\OpenAI\\Codex\\bin\\codex.exe",
        "install method": "standalone (windows, package C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc, bin C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\bin, resources C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\codex-resources, path C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-x86_64-pc-windows-msvc\\codex-path)",
        "platform": "windows-x86_64",
        "version": "0.150.1"
      },
      "remediation": null,
      "durationMs": 0
    },
    "runtime.search": {
      "id": "runtime.search",
      "category": "search",
      "status": "ok",
      "summary": "search is OK (bundled)",
      "details": {
        "search command": "C:\\Users\\crain\\.codex\\packages\\standalone\\releases\\0.150.1-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": "OnRequest",
        "codex-linux-sandbox helper": "none",
        "denied-read restrictions": "false",
        "execve wrapper helper": "none",
        "filesystem sandbox": "restricted",
        "network sandbox": "restricted",
        "sandbox backend": "elevated",
        "sandbox provisioning": "complete"
      },
      "remediation": null,
      "durationMs": 2
    },
    "security.endpoint": {
      "id": "security.endpoint",
      "category": "security",
      "status": "warning",
      "summary": "endpoint protection detected; Codex exclusions are unverified",
      "details": {
        "Codex exclusions": "not verified",
        "endpoint products": "Microsoft Defender",
        "exclusion targets": "signed Codex app; codex.exe; codex-windows-sandbox-setup.exe; codex-command-runner.exe; codex-code-mode-host.exe"
      },
      "issues": [
        {
          "severity": "warning",
          "cause": "Microsoft Defender can interfere with Codex. Verify Codex exclusions.",
          "measured": "not verified",
          "expected": "Codex application and helper exclusions",
          "remedy": "Microsoft Defender: Add a certificate or executable-path exclusion for Codex and its helpers. If Attack Surface Reduction blocks Codex, add a rule exclusion. If Controlled Folder Access blocks Codex, allow the app.",
          "fields": [
            "Codex exclusions"
          ]
        }
      ],
      "remediation": "ask your security administrator to verify Codex exclusions and required helper allowances",
      "durationMs": 20
    },
    "state.paths": {
      "id": "state.paths",
      "category": "state",
      "status": "ok",
      "summary": "state paths and databases are inspectable",
      "details": {
        "CODEX_HOME": "C:\\Users\\crain\\.codex (dir)",
        "active rollout files": "433 files, 3068000782 total bytes, 7085452 average bytes",
        "archived rollout files": "22 files, 9743582 total bytes, 442890 average bytes",
        "goals DB": "C:\\Users\\crain\\.codex\\goals_1.sqlite (file)",
        "goals DB integrity": "ok",
        "log DB": "C:\\Users\\crain\\.codex\\logs_2.sqlite (file)",
        "log DB integrity": "ok",
        "log dir": "C:\\Users\\crain\\.codex\\log (dir)",
        "memories DB": "C:\\Users\\crain\\.codex\\memories_1.sqlite (file)",
        "memories DB integrity": "ok",
        "queue DB": "C:\\Users\\crain\\.codex\\queue_1.sqlite (file)",
        "queue DB integrity": "ok",
        "sqlite home": "C:\\Users\\crain\\.codex (dir)",
        "standalone release cache": "3 entries in C:\\Users\\crain\\.codex\\packages\\standalone\\releases",
        "state DB": "C:\\Users\\crain\\.codex\\state_5.sqlite (file)",
        "state DB integrity": "ok",
        "thread history DB": "C:\\Users\\crain\\.codex\\thread_history_1.sqlite (file)",
        "thread history DB integrity": "ok"
      },
      "remediation": null,
      "durationMs": 1842
    },
    "state.rollout_db_parity": {
      "id": "state.rollout_db_parity",
      "category": "threads",
      "status": "ok",
      "summary": "rollout files and state DB thread inventory agree",
      "details": {
        "default model provider": "openai",
        "rollout DB active files": "433",
        "rollout DB active rows": "433",
        "rollout DB archive mismatches": "0",
        "rollout DB archived files": "22",
        "rollout DB archived rows": "22",
        "rollout DB duplicate DB paths": "0",
        "rollout DB duplicate rollout thread ids": "0",
        "rollout DB malformed file names": "0",
        "rollout DB missing active rows": "0",
        "rollout DB missing archived rows": "0",
        "rollout DB model providers": "openai=455",
        "rollout DB rows": "455",
        "rollout DB scan cap reached": "false",
        "rollout DB scan errors": "0",
        "rollout DB sources": "subagent:other=206, subagent:thread_spawn=145, vscode=101, cli=3",
        "rollout DB stale rows": "0"
      },
      "remediation": null,
      "durationMs": 508
    },
    "system.disk": {
      "id": "system.disk",
      "category": "disk",
      "status": "ok",
      "summary": "sufficient free disk space (13.8 GiB)",
      "details": {
        "CODEX_HOME available": "13.8 GiB",
        "failure threshold": "1.0 GiB",
        "warning threshold": "5.0 GiB",
        "worktree available": "13.8 GiB"
      },
      "remediation": null,
      "durationMs": 0
    },
    "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
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    "terminal.env": {
      "id": "terminal.env",
      "category": "terminal",
      "status": "ok",
      "summary": "terminal metadata was detected",
      "details": {
        "color output": "disabled (stdout is not a terminal)",
        "console input code page": "437",
        "console output code page": "437",
        "stderr console mode": "0x00000007 (VT processing: true)",
        "stderr is terminal": "true",
        "stdin is terminal": "true",
        "stdout console mode": "unavailable",
        "stdout is terminal": "false",
        "terminal": "unknown",
        "terminal size": "120x50"
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      "remediation": null,
      "durationMs": 0
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    "terminal.title": {
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      "status": "ok",
      "summary": "terminal title default",
      "details": {
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        "terminal title items": "activity, project-name",
        "terminal title project source": "cwd",
        "terminal title project value": "crain",
        "terminal title source": "default"
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      "remediation": null,
      "durationMs": 0
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    "updates.status": {
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      "category": "updates",
      "status": "ok",
      "summary": "update configuration is locally consistent",
      "details": {
        "cached latest version": "0.150.1",
        "check for update on startup": "true",
        "desktop application": "OpenAI.Codex",
        "desktop latest build": "26.825.4187.0",
        "desktop update status": "available",
        "last checked at": "2026-08-28T10:32:27.540755Z",
        "latest version": "0.150.1",
        "latest version status": "current version is not older",
        "update action": "standalone installer",
        "version cache": "C:\\Users\\crain\\.codex\\version.json"
      },
      "remediation": null,
      "durationMs": 378
    }
  }
}

What issue are you seeing?

The official Upwork MCP server fails during Codex CLI startup before any tools are discovered.

Configured MCP server:

https://mcp.upwork.com/mcp

OAuth authorization completes in the browser. However, when a fresh Codex session starts, Codex reports:

MCP client for upwork failed to start:
MCP startup failed: Unexpected response type

MCP startup incomplete (failed: upwork)

Running /mcp verbose shows:

• upwork: failed (0 tools)
• Auth: OAuth
• Tools: none
• Resources: none
• Resource templates: none

I reproduced this using both a project-scoped configuration and Upwork's documented CLI setup:

codex mcp add upwork --url https://mcp.upwork.com/mcp

I also disconnected the existing Upwork OAuth clients, removed the Codex MCP registration, recreated a single connection, completed OAuth again, and started a fresh Codex process. The same startup failure remained.

Other configured tool providers initialize normally, including codex_apps and node_repl.

The failure occurs before tool discovery or any Upwork tool invocation. No proposal, message, profile update, contract action, financial action, or Connects spend occurred.

What steps can reproduce the bug?

Uploaded thread: 01a04a9d-bf9c-7010-a066-316080d71277

What is the expected behavior?

Codex should complete the OAuth-authenticated MCP handshake with the official Upwork server, discover the available Upwork tools, and show the server as connected with more than zero tools when /mcp is run.

A failure in an unsupported response should identify the handshake stage and unexpected response variant rather than returning only the generic message "Unexpected response type."

Additional information

Official MCP server:
https://mcp.upwork.com/mcp

Codex CLI version:
0.150.1

Transport:
Remote Streamable HTTP MCP

Authentication:
OAuth 2.1 / dynamic client registration

The failure occurs during MCP startup before tools are discovered. This differs from related issues involving Unexpected response type during a later tools/call response after tool discovery, such as #29002, #33404, and #41280.

The following have already been attempted:

• project-scoped MCP configuration;
• official global codex mcp add configuration;
• OAuth logout and reauthorization;
• revocation of existing Upwork connected services;
• complete MCP registration removal and recreation;
• fresh Codex processes;
• minimal configuration;
• trace-level diagnostic capture.

Other MCP/tool providers in the same Codex session initialize successfully.

No Upwork write action occurred.

upwork_mcp_issue_fields.txt

upwork_mcp_reproduction_steps.txt

[oudouusa]

I can reproduce this on WSL2/Linux as well, so it does not appear to be Windows-specific.

Environment

• Codex CLI: 0.150.1
• OS: Ubuntu 26.04 on WSL2
• MCP endpoint: https://mcp.upwork.com/mcp
• Transport: Streamable HTTP
• OAuth succeeds; the stored access token is current and a refresh token is present

I captured the authenticated MCP responses. initialize succeeds with protocol 2025-06-18, and the server reports envoy-ai-gateway v1.1.0. The following list calls also return their expected data:

• tools/list: 30 tools
• resources/list: 1 resource
• resources/templates/list: 0 templates

However, all three result objects include this metadata:

{
  "ttlMs": 0,
  "cacheScope": ""
}

The MCP caching schema permits cacheScope values of "public" or "private"; an empty string is invalid. Codex 0.150.1 uses rmcp 3.1.3, whose CacheScope enum accepts only those values. Consequently, the otherwise-valid list result cannot deserialize as ListToolsResult / ListResourcesResult, falls through to a generic result variant, and Codex reports Unexpected response type.

This is consistent with the failure occurring after OAuth and initialize, but before tool discovery. Reauthentication does not fix it.

Possible fixes:

• Server side: emit a valid cache scope (likely "private" for authenticated responses), or omit the cache metadata when using the negotiated older protocol.
• Client side: ignore malformed cache-hint metadata rather than rejecting the entire otherwise-valid list response.

No Upwork write actions were performed during this diagnostic, and no credentials or session identifiers are included here.

[ishto7]

I can reproduce this on macOS as well, using the Codex desktop app on a local Mac.

Environment

• Codex CLI/runtime: 0.152.1
• Codex desktop build: 26.831.21537
• MCP endpoint: https://mcp.upwork.com/mcp
• Transport: Streamable HTTP
• OAuth authorization succeeds; an authenticated direct MCP probe succeeds
• The app recognizes the configured server, but it remains at 0 discovered tools

Sanitized app log

server=upwork status=starting
MCP client for `upwork` failed to start:
MCP startup failed: Unexpected response type
server=upwork status=failed tools=0

The failure occurs during startup before tool discovery. In a separate authenticated probe, initialize returned a valid JSON response and tools/list returned a valid SSE response containing the Upwork tools, including the same ttlMs: 0 / cacheScope: "" metadata described above.

No credentials, access tokens, usernames, local paths, thread IDs, or Upwork write actions are included or were used.

[ismail-rt]

I can reproduce this on macOS with Codex CLI 0.151.0 and the Codex desktop app.

OAuth against https://mcp.upwork.com/mcp succeeds. codex mcp login upwork completes, and codex mcp list shows the server as enabled with Auth: OAuth. A new Codex thread still has 0 Upwork tools.

This matches the earlier root cause: initialize succeeds, but tools/list / resources/list / resources/templates/list include:

{
  "ttlMs": 0,
  "cacheScope": ""
}

ttlMs: 0 is valid. cacheScope: "" is not. SEP-2549 only allows "public", "private", or omitting the field. Codex pins rmcp = 3.1.3, and that crate's CacheScope enum cannot deserialize the empty string, so the otherwise valid list result falls through ServerResult's untagged CustomResult variant. Codex then reports Unexpected response type and never imports the tools.

Re-login and a full app restart do not fix it. The stored OAuth tokens are fine; tool discovery is what fails.

Codex does not accept external code PRs, so I opened the client-side compatibility fix against rmcp:

modelcontextprotocol/rust-sdk#1241

That change treats an exact empty cacheScope as omitted on list and read results, while still rejecting unknown or whitespace values. After rmcp ships it, Codex would still need to bump the pinned rmcp version.

The durable server-side fix is for Upwork to send "private" or omit cacheScope on authenticated list responses.

[coktale]

Confirming the same pre-discovery failure on macOS:

• Codex CLI 0.148.0
• Darwin 24.6.0 arm64
• Official endpoint: https://mcp.upwork.com/mcp
• codex mcp login upwork completes successfully
• MCP status reports OAuth authentication, but serverInfo is null and tools, resources, and resource templates are empty

A transient test with mcp_2026_07_28 changed the failure to HTTP 400: missing session ID; the setting was not persisted. Upwork’s documented experimental_use_rmcp_client setting is rejected as an unknown feature in this build.

This confirms the zero-tool/pre-discovery symptom is not limited to Windows. No Upwork write action, message, saved job, or proposal submission occurred.

[prins1bap-ui]

Confirmed the same failure pattern from the current ChatGPT Upwork integration, not just Codex CLI/Desktop.

ChatGPT reproduction

• Product surface: ChatGPT Work
• Model: GPT-5.6 Sol
• Official curated Upwork plugin: plugin_asdk_app_6a75165ed2d8819182548553aa4cb6d5
• Fresh OAuth authorization completes successfully
• Plugin catalog reports installed/enabled, user-enabled, dependency-clean
• Clean uninstall/reinstall completed before retest
• Upwork-specific app permission was also tested with Full Access

Immediately after successful OAuth, the first authenticated read (list_accounts) causes the Upwork tool surface to become disabled with no usable account response. A separate authenticated read path using a previously known freelancer organization context (get_organization) reproduced the same failure, so this is not specific to the list_accounts function.

I also tested the Upwork control-plane read for tool presentation mode (set_tool_mode action=get). It fails at the same boundary.

Stronger no-org control

A further read-only control materially narrows this: get_tool_help({"tool_name":"find_jobs"}) also immediately disables the Upwork tool surface. That method requires no freelancer org UID, Connects, proposal data, marketplace job ID, or account lookup. The host returns only:

The Upwork tool has been disabled. Do not send any more messages to Upwork.

So the failure is not dependent on account discovery, principal/org binding, marketplace retrieval, or a specific business API. It occurs before ordinary Upwork tool execution can return data, consistent with the MCP response/import/session layer.

This lines up with the upstream cacheScope: "" evidence already documented in this issue and in modelcontextprotocol/rust-sdk#1241: OAuth/initialize can succeed, but malformed list-result cache metadata prevents strict clients from importing/using the otherwise-present tools.

A client-side compatibility fix is currently open at:
modelcontextprotocol/rust-sdk#1241

Server-side, the durable fix remains for https://mcp.upwork.com/mcp to emit cacheScope: "private" or omit cacheScope instead of returning an empty string on authenticated list responses.

Documentation/rollout inconsistency

There is also a current product-documentation mismatch worth noting. Upwork's official MCP page advertises direct ChatGPT Developer Mode setup against https://mcp.upwork.com/mcp and says custom MCP connectors are available on Plus/Pro/Team/Business/Enterprise. OpenAI's current Developer Mode help page says full custom MCP/developer mode is web-only and available to Business and Enterprise/Edu (with narrower Pro support noted separately), while this Plus account already has the OpenAI-curated Upwork plugin installed from the directory. This may indicate the Upwork/ChatGPT rollout surfaces are not aligned.

OpenAI support cases 14667036/14667065/14667236 and Upwork MCP support request #55494650 have the same sanitized evidence.

No Upwork write actions, proposal submissions, Connects spend, credentials, access tokens, user names, or account identifiers are included in this report.

[coktale]

Since the problem is on Upwork side, I decided to email request directly to mcp-support@upwork.com

Go on and send your problems too!

[coktale]

Upwork support replied it is fixed now, and I could re-connect via MCP and get data!

We escalated it to our engineers, who investigated the issue and made changes to address it. Things should now be working as expected.

When you have a chance, please disconnect and reconnect your Upwork integration inside Codex to ensure the update takes effect, then try again to see if the issue has been resolved for you.

Reconnection succeeded. The Upwork fix appears to have resolved the original startup failure.

- Removed the old Upwork OAuth credentials.
- Completed a fresh OAuth/DCR login.
- Started a new read-only Codex process.
- Upwork MCP initialized successfully.
- **32 tools were discovered**, including `find_jobs`, `find_saved_jobs`, `get_tool_help`, `get_profile`, and `get_freelancer_dashboard`.
- No Upwork tool was invoked and no external Upwork state changed.

The old `Unexpected response type` / zero-tools problem did not recur. The current task was initialized before reconnection, so the Upwork tools cannot be injected into its existing tool registry; a fresh task/process will load them. This matches the [[official OpenAI MCP login workflow](https://learn.chatgpt.com/docs/extend/mcp?surface=cli)](https://learn.chatgpt.com/docs/extend/mcp?surface=cli).