Codex 0.139.0 adds web search and cleaner tooling

Codex 0.139.0 adds web search, richer tool schemas, and fewer TUI and sandbox bugs.

OpenAI’s latest Codex release, 0.139.0, focuses on making agent workflows more capable and less error-prone. It ships with 151 assets and several fixes that reduce friction in the terminal, sandbox, and plugin flow.

Item	Main gain	Notable detail
Code mode web search	New capability	Standalone search calls can return plaintext results
Tool schemas	Compatibility	Preserves oneOf and allOf, keeps large schemas shallower
codex doctor	Diagnostics	Includes editor and pager environment details
Plugin marketplace	Discovery	Shows source in JSON and can use cached catalog first
Sandbox and TUI fixes	Reliability	Better resume, fork, URL linkifying, and proxy handling

1. Code mode web search

The headline feature is direct web search from code mode, including nested JavaScript tool calls. That matters for agents that need current facts without bouncing through a separate workflow or losing the result format along the way.

This is not just a convenience add-on. The release notes say search returns plaintext results, which makes downstream parsing simpler for prompts, tools, and follow-up actions.

• Release: 0.139.0
• Change: standalone web search in code mode
• Works from nested JavaScript tool calls
• Output: plaintext search results

2. Richer tool input schemas

Codex now preserves oneOf and allOf in tool input schemas, which should help it talk to MCP tools that rely on more expressive JSON Schema shapes. Large schemas also keep a shallower structure when compacted, reducing the chance that important nesting gets flattened away.

For teams building connectors or agent tooling, this is the sort of change that quietly lowers integration pain. It does not change the user interface, but it can make a big difference when tools fail because the schema got simplified too aggressively.

• Preserves oneOf and allOf
• Improves compatibility with richer MCP tools
• Keeps large schemas more shallow after compaction
• Relevant to tool authors and connector maintainers

3. Better diagnostics in codex doctor

The codex doctor command now reports editor and pager environment details in the local report. At the same time, JSON output redacts raw values, so the extra visibility does not expose the exact environment data by default.

That combination helps support debugging without making logs noisy or risky. If you have ever tried to reproduce a terminal issue and found the editor or pager setup missing from the report, this fix fills in a useful gap.

codex doctor codex doctor --json

4. Plugin marketplace flow

The plugin marketplace got two practical upgrades: codex plugin marketplace list --json now includes each marketplace source, and plugin lists can return from a cached remote catalog before refreshing in the background. That means faster feedback and more context in the data you inspect.

For people managing multiple plugin sources, source visibility matters. It makes it easier to tell where an entry came from, whether a cached result is being used, and what should be refreshed next.

• --json output includes marketplace source
• Cached remote catalog can return first
• Background refresh happens after the initial result
• Useful for plugin operators and CI checks

5. TUI and sandbox fixes

The release also cleans up a cluster of terminal and sandbox issues. Resume and fork now treat the trailing argument as the initial prompt, subagent startup warnings stay in the right thread, and image edits use the exact referenced file paths instead of guessing from conversation history.

There are smaller but welcome fixes too: bare URLs with tildes linkify correctly, thread resets keep cloud-managed requirements and feature flags, and sandbox execution preserves approved escalation decisions while enforcing proxy-only networking more consistently.

• codex resume --last and codex fork --last now read prompts correctly
• Subagent startup warnings stay in the owning thread
• Image edits use referenced file paths
• Sandbox approval and proxy settings are preserved more reliably

How to decide

If you build on Codex as an agent platform, the web search and schema changes are the most important. They expand what the tool can do and what kinds of MCP integrations it can support. If you mostly use the TUI, the resume, fork, link, and sandbox fixes will be the day-to-day wins.

For operators and maintainers, the best reason to update is the mix of better diagnostics and more predictable plugin behavior. This release is less about a single flashy feature than about making the system easier to trust in real use.