Codex `0.123.0` adds Amazon Bedrock provider and MCP diagnostics
OpenAI's Codex CLI `0.123.0` ships a built-in Amazon Bedrock model provider, verbose MCP diagnostics, improved realtime agent handoffs, and a slate of bug fixes including Unicode input and `/copy` rollback corrections.
Score breakdown
Teams using Codex with AWS infrastructure can now route requests through Amazon Bedrock natively, while the MCP diagnostics command and `.mcp.json` flexibility reduce friction when configuring and debugging multi-server agentic setups.
- 01Built-in `amazon-bedrock` model provider added with configurable AWS profile support.
- 02New `/mcp verbose` command exposes full MCP server diagnostics, resources, and resource templates without slowing down plain `/mcp`.
- 03Plugin MCP loading now accepts both `mcpServers` and top-level server maps in `.mcp.json`.
Codex `0.123.0` expands model provider support by adding a built-in `amazon-bedrock` provider with configurable AWS profile support, giving users a native path to run Codex against AWS-hosted models. The release also introduces `/mcp verbose` for full MCP server diagnostics, resources, and resource templates, while keeping the plain `/mcp` command lightweight. Plugin MCP loading was made more flexible, now accepting both `mcpServers` and top-level server maps in `.mcp.json`. Realtime handoff behavior was improved across multiple pull requests so that background agents receive transcript deltas and can explicitly invoke a silence tool when staying quiet is appropriate. Host-specific `remote_sandbox_config` requirements were added for remote environments, and bundled model metadata was refreshed to reflect `gpt-5.4` as the current default.
The bug fix section addresses several quality-of-life issues: `/copy` after a rollback now correctly copies the latest visible assistant response rather than a pre-rollback one; normal follow-up text submitted while a manual shell command is running is now queued instead of causing a stuck `Working` state; Unicode and dead-key input in VS Code WSL terminals is fixed by disabling enhanced keyboard mode in that context; stale proxy environment variables are no longer incorrectly restored from shell snapshots; and `codex exec` now properly inherits root-level shared flags such as sandbox and model options. On the documentation and maintenance side, Code Review skill instructions were added and tightened, Clippy linting was enabled for intentional await-across-lock cases, high-severity dependency alerts were resolved by pinning patched JS and Rust dependencies, and Rust dev build debug-info overhead was reduced while preserving useful backtraces.
Key facts
- 01Built-in `amazon-bedrock` model provider added with configurable AWS profile support.
- 02New `/mcp verbose` command exposes full MCP server diagnostics, resources, and resource templates without slowing down plain `/mcp`.
- 03Plugin MCP loading now accepts both `mcpServers` and top-level server maps in `.mcp.json`.
- 04Realtime handoffs improved: background agents receive transcript deltas and can invoke an explicit silence tool.
- 05Bundled model metadata refreshed with `gpt-5.4` as the current default.
- 06`/copy` after rollback fixed to copy the latest visible assistant response, not a pre-rollback one.
- 07Unicode and dead-key input in VS Code WSL terminals fixed by disabling enhanced keyboard mode there.