## What changed
- Add `http_headers_helper` configuration for local streamable HTTP MCP servers. The configured shell command runs once per connection and returns a JSON object of headers that is cached across requests.
- Apply helper headers to MCP startup and OAuth flows while restricting them to the server origin, stopping redirects, rejecting reserved or duplicate headers, and enforcing output and execution limits.
- Reject helpers for remote or managed-disabled servers, use the local environment working directory, and redact helper commands from `codex mcp list` and `codex mcp get` output.
## Testing
- Cover configuration validation, helper lifecycle and output parsing, origin isolation, OAuth discovery and token refresh, managed requirements, environment selection, and CLI redaction.
GitOrigin-RevId: 84e0e26ce75520b0869d37c72b1678e033bd6818
## Why
OAuth discovery failures do not establish that an MCP server lacks OAuth
support. Reporting those failures as `unsupported` conflates an inconclusive
check with a confirmed result.
## What changed
- Add an `unknown` MCP authentication status across the protocol, app server,
CLI, and TUI.
- Preserve OAuth discovery errors so callers can report `unknown`, while
retaining `unsupported` for servers known not to support OAuth.
- Document the distinction in the app server API.
## Testing
- Verify transient HTTP discovery errors are preserved.
- Verify `codex mcp list --json` reports `unknown` when discovery is rate
limited.
GitOrigin-RevId: e4562985971606740538e542ec7eeee502111964
## What changed
- Update the Rust MCP SDK from `3.0.0-beta.3` to `3.0.0` and adapt to its renamed metadata and server discovery types.
- Accept discovery responses without server identity metadata, using the configured server name as a fallback, and rely on the SDK's native support for namespaced server identity metadata.
- Preserve typed OAuth HTTP errors so transport failures, cross-origin redirects, and transient HTTP responses are reported instead of being treated as anonymous access.
## Testing
- Cover modern discovery with namespaced or missing server identity over HTTP, SSE, and stdio.
- Cover OAuth discovery error propagation for transport failures, redirects, and transient status codes.
GitOrigin-RevId: 12c1e45136cca89ce4fb15986c2b5df14608682a
## Why
Curated plugin capabilities need to follow the active authentication mode, including after an account switch and when the configured model provider differs from the authentication source.
## What changed
- Select the ChatGPT, remote, or API curated marketplace from the current authentication mode, with an API marketplace fallback for ambient Amazon Bedrock credentials.
- Apply that selection consistently to plugin loading, hooks, skills, installed-plugin conflict filtering, marketplace listing, and `codex mcp` discovery.
- Start the local curated repository sync when an account change makes the remote catalog unavailable, and refresh existing thread MCP runtimes when the effective plugin cache changes.
## Testing
Added coverage for account switches, ChatGPT-authenticated Bedrock sessions, API-key MCP discovery, curated marketplace filtering, hook and skill routing, and existing-thread MCP refreshes.
GitOrigin-RevId: dbefdba3a3ea7281e7b6013e057a418770ccfc95
## Why
MCP authentication checks need to use the same HTTP routing as the MCP
transport so servers reached through configured proxies can be discovered
reliably.
## What changed
- Resolve OAuth discovery and authentication status through each server's
runtime HTTP client for both local and managed environments.
- Keep local discovery capped at five seconds while allowing explicit login
requests to retain their requested timeout.
- Resolve refreshed MCP configuration and its runtime context from the same
snapshot.
## Testing
- Cover OAuth discovery through an environment proxy and macOS system proxy
resolution.
- Cover proxied MCP startup and runtime refresh with updated authorization
headers.
- Verify capped and preserved OAuth discovery timeout policies.
GitOrigin-RevId: 461fb1d4786e547df8b1e6b2215a8ac40438a3aa
## Summary
- Add the executor-backed RMCP stdio transport.
- Wire MCP stdio placement through the executor environment config.
- Cover local and executor-backed stdio paths with the existing MCP test
helpers.
## Stack
```text
o #18027 [6/6] Fail exec client operations after disconnect
│
@ #18212 [5/6] Wire executor-backed MCP stdio
│
o #18087 [4/6] Abstract MCP stdio server launching
│
o #18020 [3/6] Add pushed exec process events
│
o #18086 [2/6] Support piped stdin in exec process API
│
o #18085 [1/6] Add MCP server environment config
│
o main
```
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
This finishes the config-type move out of `codex-core` by removing the
temporary compatibility shim in `codex_core::config::types`. Callers now
depend on `codex-config` directly, which keeps these config model types
owned by the config crate instead of re-expanding `codex-core` as a
transitive API surface.
## What Changed
- Removed the `codex-rs/core/src/config/types.rs` re-export shim and the
`core::config::ApprovalsReviewer` re-export.
- Updated `codex-core`, `codex-cli`, `codex-tui`, `codex-app-server`,
`codex-mcp-server`, and `codex-linux-sandbox` call sites to import
`codex_config::types` directly.
- Added explicit `codex-config` dependencies to downstream crates that
previously relied on the `codex-core` re-export.
- Regenerated `codex-rs/core/config.schema.json` after updating the
config docs path reference.
This PR introduces a `codex-utils-cargo-bin` utility crate that
wraps/replaces our use of `assert_cmd::Command` and
`escargot::CargoBuild`.
As you can infer from the introduction of `buck_project_root()` in this
PR, I am attempting to make it possible to build Codex under
[Buck2](https://buck2.build) as well as `cargo`. With Buck2, I hope to
achieve faster incremental local builds (largely due to Buck2's
[dice](https://buck2.build/docs/insights_and_knowledge/modern_dice/)
build strategy, as well as benefits from its local build daemon) as well
as faster CI builds if we invest in remote execution and caching.
See
https://buck2.build/docs/getting_started/what_is_buck2/#why-use-buck2-key-advantages
for more details about the performance advantages of Buck2.
Buck2 enforces stronger requirements in terms of build and test
isolation. It discourages assumptions about absolute paths (which is key
to enabling remote execution). Because the `CARGO_BIN_EXE_*` environment
variables that Cargo provides are absolute paths (which
`assert_cmd::Command` reads), this is a problem for Buck2, which is why
we need this `codex-utils-cargo-bin` utility.
My WIP-Buck2 setup sets the `CARGO_BIN_EXE_*` environment variables
passed to a `rust_test()` build rule as relative paths.
`codex-utils-cargo-bin` will resolve these values to absolute paths,
when necessary.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/8496).
* #8498
* __->__ #8496
The goal is to have a single place where we actually write files
In a follow-up PR, will move everything config related in a dedicated
module and move the helpers in a dedicated file
Some MCP servers expose a lot of tools. In those cases, it is reasonable
to allow/denylist tools for Codex to use so it doesn't get overwhelmed
with too many tools.
The new configuration options available in the `mcp_server` toml table
are:
* `enabled_tools`
* `disabled_tools`
Fixes#4796
This makes stdio mcp servers more flexible by allowing users to specify
the cwd to run the server command from and adding additional environment
variables to be passed through to the server.
Example config using the test server in this repo:
```toml
[mcp_servers.test_stdio]
cwd = "/Users/<user>/code/codex/codex-rs"
command = "cargo"
args = ["run", "--bin", "test_stdio_server"]
env_vars = ["MCP_TEST_VALUE"]
```
@bolinfest I know you hate these env var tests but let's roll with this
for now. I may take a stab at the env guard + serial macro at some
point.
This adds a queryable auth status for MCP servers which is useful:
1. To determine whether a streamable HTTP server supports auth or not
based on whether or not it supports RFC 8414-3.2
2. Allow us to build a better user experience on top of MCP status
This PR adds support for streamable HTTP MCP servers when the
`experimental_use_rmcp_client` is enabled.
To set one up, simply add a new mcp server config with the url:
```
[mcp_servers.figma]
url = "http://127.0.0.1:3845/mcp"
```
It also supports an optional `bearer_token` which will be provided in an
authorization header. The full oauth flow is not supported yet.
The config parsing will throw if it detects that the user mixed and
matched config fields (like command + bearer token or url + env).
The best way to review it is to review `core/src` and then
`rmcp-client/src/rmcp_client.rs` first. The rest is tests and
propagating the `Transport` struct around the codebase.
Example with the Figma MCP:
<img width="5084" height="1614" alt="CleanShot 2025-09-26 at 13 35 40"
src="https://github.com/user-attachments/assets/eaf2771e-df3e-4300-816b-184d7dec5a28"
/>
