provider_model_ids("bedrock") fell through to a static _PROVIDER_MODELS
table containing only hardcoded us.* model IDs. Users configured for
non-US AWS regions (eu-central-1, ap-northeast-1, etc.) saw wrong or no
models in /model and autocomplete.
Root causes fixed:
1. models.py: provider_model_ids() now calls discover_bedrock_models()
keyed by the resolved region before falling back to the static table.
A new bedrock_model_ids_or_none() helper in bedrock_adapter.py
consolidates the discover -> extract IDs -> fallback pattern used by
all three call sites.
2. providers.py: registers bedrock in HERMES_OVERLAYS with
transport=bedrock_converse and auth_type=aws_sdk so
get_provider("bedrock") and resolve_provider_full("bedrock") work.
3. model_switch.py: list_authenticated_providers() sections 2 and 3
detect AWS credentials via has_aws_credentials() for aws_sdk
overlays and use live discovery for the model list.
4. bedrock_adapter.py: resolve_bedrock_region() reads the configured
region from botocore.session before falling back to us-east-1,
covering users who set their region in ~/.aws/config via a named
profile rather than env vars.
5. tui_gateway/server.py: passes provider= to get_model_context_length()
so context window lookups work correctly for the Bedrock provider.
## Problem
When a pooled HTTPS connection to the Bedrock runtime goes stale (NAT
timeout, VPN flap, server-side TCP RST, proxy idle cull), the next
Converse call surfaces as one of:
* botocore.exceptions.ConnectionClosedError / ReadTimeoutError /
EndpointConnectionError / ConnectTimeoutError
* urllib3.exceptions.ProtocolError
* A bare AssertionError raised from inside urllib3 or botocore
(internal connection-pool invariant check)
The agent loop retries the request 3x, but the cached boto3 client in
_bedrock_runtime_client_cache is reused across retries — so every
attempt hits the same dead connection pool and fails identically.
Only a process restart clears the cache and lets the user keep working.
The bare-AssertionError variant is particularly user-hostile because
str(AssertionError()) is an empty string, so the retry banner shows:
⚠️ API call failed: AssertionError
📝 Error:
with no hint of what went wrong.
## Fix
Add two helpers to agent/bedrock_adapter.py:
* is_stale_connection_error(exc) — classifies exceptions that
indicate dead-client/dead-socket state. Matches botocore
ConnectionError + HTTPClientError subtrees, urllib3
ProtocolError / NewConnectionError, and AssertionError
raised from a frame whose module name starts with urllib3.,
botocore., or boto3.. Application-level AssertionErrors are
intentionally excluded.
* invalidate_runtime_client(region) — per-region counterpart to
the existing reset_client_cache(). Evicts a single cached
client so the next call rebuilds it (and its connection pool).
Wire both into the Converse call sites:
* call_converse() / call_converse_stream() in
bedrock_adapter.py (defense-in-depth for any future caller)
* The two direct client.converse(**kwargs) /
client.converse_stream(**kwargs) call sites in run_agent.py
(the paths the agent loop actually uses)
On a stale-connection exception, the client is evicted and the
exception re-raised unchanged. The agent's existing retry loop then
builds a fresh client on the next attempt and recovers without
requiring a process restart.
## Tests
tests/agent/test_bedrock_adapter.py gets three new classes (14 tests):
* TestInvalidateRuntimeClient — per-region eviction correctness;
non-cached region returns False.
* TestIsStaleConnectionError — classifies botocore
ConnectionClosedError / EndpointConnectionError /
ReadTimeoutError, urllib3 ProtocolError, library-internal
AssertionError (both urllib3.* and botocore.* frames), and
correctly ignores application-level AssertionError and
unrelated exceptions (ValueError, KeyError).
* TestCallConverseInvalidatesOnStaleError — end-to-end: stale
error evicts the cached client, non-stale error (validation)
leaves it alone, successful call leaves it cached.
All 116 tests in test_bedrock_adapter.py pass.
Signed-off-by: Andre Kurait <andrekurait@gmail.com>
