Program.cs#CreateOpenAiClient previously read the OpenAI endpoint solely from
the OPENAI_BASE_URL environment variable and fell back to
ApiKeyResolver.DefaultOpenAiEndpoint. The secondary tool-calling HTTP client
(A2uiSecondaryToolCaller) instead routes through ApiKeyResolver.ResolveEndpoint,
which checks env, then configuration[OPENAI_BASE_URL] (appsettings.json /
user-secrets), then the default.
When OPENAI_BASE_URL was supplied only via configuration (e.g. user-secrets in
local dev), the primary client silently dialed the public Azure-hosted models
endpoint while the secondary client dialed the configured aimock. The two
endpoints diverged with no visible signal, breaking aimock-routed flows and
masking misconfigurations.
Switch CreateOpenAiClient to call ApiKeyResolver.ResolveEndpoint so both
clients share a single source of truth. Logging is preserved and now reports
which source supplied the endpoint (env, configuration, or default).
- Replace silent `return null` paths in A2uiSecondaryToolCaller with
TryGetProperty guards that each emit a structured LogWarning naming
the exact missing/unexpected field (choices, message, tool_calls,
function, name mismatch, arguments). Callers can now tell why a
design-tool call produced no content.
- Add ILogger parameter to GetDesignToolArgumentsAsync and pass
BeautifulChatAgent._logger from the single call site so warnings
flow into the existing log stream.
- Log the response body (truncated to 1 KB) at LogWarning before
EnsureSuccessStatusCode throws, so upstream error payloads survive
the throw and reach operators.
- Extract the OPENAI_API_KEY/GitHubToken/sk-mock-local fallback chain
from Program.cs and A2uiSecondaryToolCaller.cs into a new
ApiKeyResolver helper. Both call sites now share one implementation.
- ApiKeyResolver fails fast with InvalidOperationException + LogCritical
when no real key is present and OPENAI_BASE_URL is not an
aimock/localhost endpoint, so misconfigured prod deploys cannot
silently send sk-mock-local to a real LLM provider. The silent
mock-key fallback is preserved for aimock/localhost dev endpoints.
Jordan Ritter