## Why
The Amazon Bedrock model provider currently discards the shared
`AuthManager`, so a Codex-managed Bedrock API key cannot reach
request-time provider auth. Bedrock instead falls through to AWS
environment or SDK credentials, and the request endpoint can be resolved
from a different region than the managed credential.
Managed Bedrock login should control both the bearer credential and
Mantle region. Unrelated OpenAI or ChatGPT credentials must remain
isolated from Bedrock.
## What changed
- Pass the shared `AuthManager` into `AmazonBedrockModelProvider`.
- Select `CodexAuth::BedrockApiKey` before the existing
`AWS_BEARER_TOKEN_BEDROCK` and AWS SDK/SigV4 paths.
- Use the managed Bedrock auth region when resolving the Mantle
endpoint.
- Filter other `CodexAuth` variants so OpenAI and ChatGPT auth are not
exposed to Bedrock request auth or unauthorized recovery.
- Add focused coverage for provider construction, managed-auth
precedence, bearer headers, endpoint selection, and OpenAI-auth
isolation.
This reverts commit 5381240f57. Gov cloud
should not be supported
# External (non-OpenAI) Pull Request Requirements
External code contributions are by invitation only. Please read the
dedicated "Contributing" markdown file for details:
https://github.com/openai/codex/blob/main/docs/contributing.md
If your PR conforms to our contribution guidelines, replace this text
with a detailed and high quality description of your changes.
Include a link to a bug report or enhancement request.
## Summary
- Add us-gov-west-1 to the Bedrock Mantle supported region list
- Cover the GovCloud endpoint URL in the existing base_url unit test
## Test
- cargo test -p codex-model-provider
## Why
`/status` was showing the configured `ModelProviderInfo.base_url` for
Amazon Bedrock, which can be stale or misleading because the actual
Bedrock Mantle endpoint is derived at runtime from the resolved AWS
region. This made sessions report the wrong provider endpoint even
though requests used the correct runtime URL.
## What changed
- Added `ModelProvider::runtime_base_url()` so provider implementations
can expose the request-time base URL through the shared runtime provider
abstraction.
- Moved Bedrock region-to-Mantle URL resolution into
`amazon_bedrock::mantle::runtime_base_url()`, keeping region resolution
private to the Mantle module.
- Overrode `runtime_base_url()` for Amazon Bedrock so it returns the
resolved Mantle endpoint instead of the configured default.
- Resolved and cached the runtime provider base URL during TUI startup,
then used that cached value when rendering `/status`.
- Added status coverage that verifies Bedrock displays the runtime URL
and ignores the configured Bedrock `base_url` when they differ.
## Verification
model provider is resolved correctly in local build:
<img width="696" height="245" alt="Screenshot 2026-04-29 at 5 01 36 PM"
src="https://github.com/user-attachments/assets/a13c10a5-3720-41ab-8ace-3c4bc573f971"
/>
## Summary
Amazon Bedrock Mantle's OpenAI-compatible endpoint now lives under
`/openai/v1`, and the GPT-5.4 Mantle model ID no longer uses the `-cmb`
suffix. This updates Codex's built-in Bedrock provider configuration so
generated providers and the static Bedrock catalog use the current
endpoint and model ID.
## Changes
- Update the Bedrock Mantle base URL from
`https://bedrock-mantle.{region}.api.aws/v1` to
`https://bedrock-mantle.{region}.api.aws/openai/v1`.
- Update the Amazon Bedrock default base URL in
`codex-model-provider-info`.
- Change the Bedrock GPT-5.4 catalog slug from `openai.gpt-5.4-cmb` to
`openai.gpt-5.4`.
- Align provider and catalog tests with the new URL and model ID.
## Test Plan
- Manual smoke test:
```shell
target/debug/codex \
-m openai.gpt-5.4 \
-c 'model_provider="amazon-bedrock"' \
-c 'model_providers.amazon-bedrock.aws.region="us-west-2"'
```
## Summary
Add first-class Amazon Bedrock Mantle provider support so Codex can keep
using its existing Responses API transport with OpenAI-compatible
AWS-hosted endpoints such as AOA/Mantle.
This is needed for the AWS launch path, where provider traffic should
authenticate with AWS credentials instead of OpenAI bearer credentials.
Requests are authenticated immediately before transport send, so SigV4
signs the final method, URL, headers, and body bytes that `reqwest` will
send.
## What Changed
- Added a new `codex-aws-auth` crate for loading AWS SDK config,
resolving credentials, and signing finalized HTTP requests with AWS
SigV4.
- Added a built-in `amazon-bedrock` provider that targets Bedrock Mantle
Responses endpoints, defaults to `us-east-1`, supports region/profile
overrides, disables WebSockets, and does not require OpenAI auth.
- Added Amazon Bedrock auth resolution in `codex-model-provider`: prefer
`AWS_BEARER_TOKEN_BEDROCK` when set, otherwise use AWS SDK credentials
and SigV4 signing.
- Added `AuthProvider::apply_auth` and `Request::prepare_body_for_send`
so request-signing providers can sign the exact outbound request after
JSON serialization/compression.
- Determine the region by taking the `aws.region` config first (required
for bearer token codepath), and fallback to SDK default region.
## Testing
Amazon Bedrock Mantle Responses paths:
- Built the local Codex binary with `cargo build`.
- Verified the custom proxy-backed `aws` provider using `env_key =
"AWS_BEARER_TOKEN_BEDROCK"` streamed raw `responses` output with
`response.output_text.delta`, `response.completed`, and `mantle-env-ok`.
- Verified a full `codex exec --profile aws` turn returned
`mantle-env-ok`.
- Confirmed the custom provider used the bearer env var, not AWS profile
auth: bogus `AWS_PROFILE` still passed, empty env var failed locally,
and malformed env var reached Mantle and failed with `401
invalid_api_key`.
- Verified built-in `amazon-bedrock` with `AWS_BEARER_TOKEN_BEDROCK` set
passed despite bogus AWS profiles, returning `amazon-bedrock-env-ok`.
- Verified built-in `amazon-bedrock` SDK/SigV4 auth passed with
`AWS_BEARER_TOKEN_BEDROCK` unset and temporary AWS session env
credentials, returning `amazon-bedrock-sdk-env-ok`.
Celia Chen