fix(inference): fail closed when BYOK intent cannot resolve a provider (#2489)

src/openhuman/inference/provider/factory.rs

@@ -35,6 +35,12 @@ use crate::openhuman::inference::provider::ProviderRuntimeOptions;
 pub const PROVIDER_OPENHUMAN: &str = "openhuman";
 /// Prefix for Ollama-local providers: `"ollama:<model>"`.
 pub const OLLAMA_PROVIDER_PREFIX: &str = "ollama:";
+/// Sentinel returned when a user has expressed custom/BYOK inference intent
+/// (via a non-openhuman `inference_url`) but no matching `cloud_providers`
+/// entry was found. Passed through `provider_for_role` and caught early in
+/// `create_chat_provider_from_string` to produce a clear configuration error
+/// instead of silently routing through the managed OpenHuman backend.
+pub const BYOK_INCOMPLETE_SENTINEL: &str = "__byok_incomplete__";
 
 fn is_abstract_tier_model(model: &str) -> bool {
     use crate::openhuman::config::{
@@ -149,6 +155,24 @@ pub fn create_chat_provider_from_string(
         p
     );
 
+    // Fail-closed: BYOK intent was detected upstream but no matching provider
+    // entry was found. Surface a clear configuration error instead of silently
+    // routing through the managed OpenHuman backend.
+    if p == BYOK_INCOMPLETE_SENTINEL {
+        let inference_url = config
+            .inference_url
+            .as_deref()
+            .filter(|s| !s.trim().is_empty())
+            .unwrap_or("<unset>");
+        anyhow::bail!(
+            "[chat-factory] BYOK_INCOMPLETE: inference_url is set to a custom/direct endpoint \
+             ({inference_url}) but no matching cloud_providers entry was found for role '{role}'. \
+             To complete BYOK setup add a cloud_providers entry whose endpoint matches \
+             {inference_url} (or use a workload-specific route). \
+             To use the OpenHuman managed backend instead, clear inference_url from config."
+        );
+    }
+
     // Empty / legacy "cloud" sentinel → primary cloud target.
     if p.is_empty() || p == "cloud" {
         let resolved = resolve_primary_cloud_provider_string(config);
@@ -332,14 +356,80 @@ fn resolve_primary_cloud_provider_string(config: &Config) -> String {
         if let Some(legacy) = legacy_custom_inference_provider_string(config) {
             return legacy;
         }
+        // Primary is explicitly OpenHuman but inference_url points at a custom
+        // endpoint with no matching provider entry — this is a half-migrated BYOK
+        // config. Fail closed so the user sees an actionable error rather than
+        // silently routing through the managed backend.
+        if has_custom_inference_intent(config) {
+            log::debug!(
+                "[providers][chat-factory] BYOK intent detected (host={}) \
+                 but no matching cloud_providers entry found; returning fail-closed sentinel",
+                redact_inference_url(config.inference_url.as_deref())
+            );
+            return BYOK_INCOMPLETE_SENTINEL.to_string();
+        }
     }
 
     if let Some(entry) = primary {
         return cloud_entry_provider_string(entry, config);
     }
 
-    legacy_custom_inference_provider_string(config)
-        .unwrap_or_else(|| PROVIDER_OPENHUMAN.to_string())
+    // No explicit primary configured. If inference_url signals custom intent but
+    // no matching provider entry exists, fail closed instead of falling back to
+    // the managed backend.
+    legacy_custom_inference_provider_string(config).unwrap_or_else(|| {
+        if has_custom_inference_intent(config) {
+            log::debug!(
+                "[providers][chat-factory] BYOK intent detected (host={}) \
+                 with no primary_cloud and no matching provider entry; returning fail-closed sentinel",
+                redact_inference_url(config.inference_url.as_deref())
+            );
+            BYOK_INCOMPLETE_SENTINEL.to_string()
+        } else {
+            PROVIDER_OPENHUMAN.to_string()
+        }
+    })
+}
+
+/// Extract the host portion of an inference URL for safe logging.
+///
+/// Returns the host (e.g. `"api.example.com"`) so log lines are grep-friendly
+/// without exposing tokens or credentials that may appear in query-string or
+/// path components of a bearer-auth URL (e.g. `"https://host/v1?key=…"`).
+/// Falls back to `"<redacted>"` when the URL cannot be parsed or is absent.
+fn redact_inference_url(url: Option<&str>) -> &str {
+    url.and_then(|u| {
+        // Minimal host extraction: find the authority after "://".
+        let after_scheme = u.find("://").map(|i| &u[i + 3..])?;
+        // Authority ends at '/', '?', '#', or end-of-string.
+        let host_end = after_scheme
+            .find(['/', '?', '#'])
+            .unwrap_or(after_scheme.len());
+        let authority = &after_scheme[..host_end];
+        // Strip optional "user:pass@" and port.
+        let host = authority
+            .rfind('@')
+            .map_or(authority, |i| &authority[i + 1..]);
+        let host = host.rfind(':').map_or(host, |i| &host[..i]);
+        if host.is_empty() {
+            None
+        } else {
+            Some(host)
+        }
+    })
+    .unwrap_or("<redacted>")
+}
+
+/// Return `true` when the config contains a non-openhuman `inference_url`,
+/// indicating the user intends custom/BYOK routing rather than the managed
+/// backend.
+fn has_custom_inference_intent(config: &Config) -> bool {
+    config
+        .inference_url
+        .as_deref()
+        .map(str::trim)
+        .filter(|url| !url.is_empty())
+        .is_some_and(|url| !looks_like_openhuman_backend(url))
 }
 
 fn legacy_custom_inference_provider_string(config: &Config) -> Option<String> {

src/openhuman/inference/provider/factory_test.rs

@@ -458,7 +458,10 @@ fn legacy_inference_url_custom_provider_wins_over_openhuman_primary_for_unset_ro
 }
 
 #[test]
-fn legacy_inference_url_without_matching_provider_stays_on_openhuman_primary() {
+fn legacy_inference_url_without_matching_provider_returns_byok_sentinel() {
+    // BYOK intent: primary is OpenHuman but inference_url points at a custom
+    // endpoint with no matching cloud_providers entry. Must fail closed — do
+    // NOT silently route through the managed backend.
     let mut other = openai_entry("p_other", "other");
     other.endpoint = "https://other.example.com/v1".to_string();
 
@@ -466,7 +469,10 @@ fn legacy_inference_url_without_matching_provider_stays_on_openhuman_primary() {
     config.primary_cloud = Some("p_oh".to_string());
     config.inference_url = Some("https://api.example.com/v1".to_string());
 
-    assert_eq!(provider_for_role("reasoning", &config), "openhuman");
+    assert_eq!(
+        provider_for_role("reasoning", &config),
+        BYOK_INCOMPLETE_SENTINEL
+    );
 }
 
 #[test]
@@ -708,3 +714,87 @@ fn make_openhuman_backend_keeps_reasoning_quick() {
     let (_, model) = make_openhuman_backend(&config).expect("factory should succeed");
     assert_eq!(model, "reasoning-quick-v1");
 }
+
+// ── BYOK fail-closed tests ────────────────────────────────────────────────────
+
+#[test]
+fn byok_intent_no_primary_no_matching_entry_returns_sentinel() {
+    // No primary_cloud set, inference_url points at a non-openhuman host with
+    // no matching cloud_providers entry → must return the fail-closed sentinel.
+    let mut config = Config::default();
+    config.inference_url = Some("https://custom-api.example.com/v1".to_string());
+    assert_eq!(
+        provider_for_role("reasoning", &config),
+        BYOK_INCOMPLETE_SENTINEL
+    );
+}
+
+#[test]
+fn byok_intent_with_matching_entry_resolves_correctly() {
+    // Matching cloud_providers entry exists → legacy lookup succeeds; no sentinel.
+    let mut custom = openai_entry("p_custom", "custom");
+    custom.endpoint = "https://custom-api.example.com/v1".to_string();
+
+    let mut config = config_with_providers(vec![custom]);
+    config.inference_url = Some("https://custom-api.example.com/v1".to_string());
+
+    // Legacy URL matches the custom entry → "custom:gpt-4o"
+    assert_eq!(provider_for_role("reasoning", &config), "custom:gpt-4o");
+}
+
+#[test]
+fn openhuman_inference_url_never_triggers_sentinel() {
+    // inference_url pointing at the managed backend is not BYOK intent.
+    let mut config = Config::default();
+    config.inference_url = Some("https://api.openhuman.ai/v1".to_string());
+    assert_eq!(provider_for_role("reasoning", &config), "openhuman");
+}
+
+#[test]
+fn explicit_workload_route_bypasses_byok_sentinel() {
+    // A per-role provider route set explicitly always wins over the BYOK check.
+    let mut config = Config::default();
+    config.inference_url = Some("https://custom-api.example.com/v1".to_string());
+    config.reasoning_provider = Some("openhuman".to_string());
+    // Explicit "openhuman" route → goes straight to backend, no sentinel.
+    assert_eq!(provider_for_role("reasoning", &config), "openhuman");
+}
+
+#[test]
+fn byok_sentinel_makes_provider_creation_error_with_clear_message() {
+    let mut config = Config::default();
+    config.inference_url = Some("https://custom-api.example.com/v1".to_string());
+
+    // Use match instead of unwrap_err(): Box<dyn Provider> doesn't impl Debug.
+    let msg = match create_chat_provider_from_string("reasoning", BYOK_INCOMPLETE_SENTINEL, &config)
+    {
+        Ok(_) => panic!("sentinel must produce an error, not a provider"),
+        Err(e) => e.to_string(),
+    };
+    assert!(
+        msg.contains("BYOK_INCOMPLETE"),
+        "error must name BYOK_INCOMPLETE; got: {msg}"
+    );
+    assert!(
+        msg.contains("custom-api.example.com"),
+        "error must include the configured inference_url; got: {msg}"
+    );
+}
+
+#[test]
+fn byok_sentinel_error_mentions_configuration_action() {
+    // The error message must tell the user how to fix the issue.
+    let mut config = Config::default();
+    config.inference_url = Some("https://byok.example.com/v1".to_string());
+
+    // Use match instead of unwrap_err(): Box<dyn Provider> doesn't impl Debug.
+    let msg = match create_chat_provider_from_string("chat", BYOK_INCOMPLETE_SENTINEL, &config) {
+        Ok(_) => panic!("sentinel must produce an error"),
+        Err(e) => e.to_string(),
+    };
+    // Must mention adding a cloud_providers entry or clearing inference_url.
+    assert!(
+        msg.contains("cloud_providers") || msg.contains("inference_url"),
+        "error must suggest a remediation; got: {msg}"
+    );
+}

src/openhuman/inference/provider/mod.rs

@@ -29,5 +29,5 @@ pub use traits::{
 
 pub use billing_error::is_budget_exhausted_message;
 pub use config_rejection::is_provider_config_rejection_message;
-pub use factory::{create_chat_provider, provider_for_role};
+pub use factory::{create_chat_provider, provider_for_role, BYOK_INCOMPLETE_SENTINEL};
 pub use ops::*;