get_builtin_overrides() was swallowing all exceptions with a bare
`except Exception: pass`, so misconfigured tool-description overrides
would silently produce wrong agent behaviour with no log trace.
The background endpoint refresh loop had the same pattern: any probe
failure was silently ignored, giving operators no signal that the
refresh was broken.
Also removes a circular self-import (`from src.agent_loop import
_build_base_prompt`) inside _build_system_prompt; the function is
already in scope and the import created a latent circular reference risk.
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
ModelEndpoint is defined in core.database, not src.database. The wrong
import silently prevented the module from loading in deployment
configurations that do not have a src/database.py shim, resulting in an
ImportError at startup.
Also adds a warning log when resolve_endpoint finds no usable model
(all models hidden or the list is empty), making the otherwise-silent
failure visible in operator logs.
The test_auth_regressions stub for src.endpoint_resolver was missing the
build_models_url attribute, which caused test collection errors.
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
