fix: address Copilot PR review feedback

- Fix empty text part for assistant messages with tool calls
  (curate_contents could drop entire model turn)
- Propagate cache_read/creation_input_tokens in complete_with_tools
- Log warning on save_credential failure instead of silently ignoring
- Fix doc comment to mention underscore in header name pattern
- Handle gemini-oauth (hyphen variant) in setup wizard display
- Fix docs: thinkingConfig uses thinkingBudget/thinkingLevel, not
  includeThoughts

FEATURE_PARITY.md

@@ -205,7 +205,7 @@ This document tracks feature parity between IronClaw (Rust implementation) and O
 | Skills (modular capabilities) | ✅ | ✅ | Prompt-based skills with trust gating, attenuation, activation criteria, catalog, selector |
 | Skill routing blocks | ✅ | 🚧 | ActivationCriteria (keywords, patterns, tags) but no "Use when / Don't use when" blocks |
 | Skill path compaction | ✅ | ❌ | ~ prefix to reduce prompt tokens |
-| Thinking modes (off/minimal/low/medium/high/xhigh/adaptive) | ✅ | 🚧 | thinkingConfig for Gemini models (includeThoughts); no per-level control yet |
+| Thinking modes (off/minimal/low/medium/high/xhigh/adaptive) | ✅ | 🚧 | thinkingConfig for Gemini models (thinkingBudget/thinkingLevel); no per-level control yet |
 | Per-model thinkingDefault override | ✅ | ❌ | Override thinking level per model; Anthropic Claude 4.6 defaults to adaptive |
 | Block-level streaming | ✅ | ❌ | |
 | Tool-level streaming | ✅ | ❌ | |

docs/LLM_PROVIDERS.md

@@ -78,7 +78,7 @@ GEMINI_MODEL=gemini-2.5-flash
 |---|---|---|
 | Function calling | ✅ | `functionDeclarations` / `functionCall` / `functionResponse` |
 | `generationConfig` | ✅ | `temperature`, `maxOutputTokens` passed from request |
-| `thinkingConfig` | ✅ | `includeThoughts: true` for `gemini-3`/`thinking` models |
+| `thinkingConfig` | ✅ | `thinkingBudget`/`thinkingLevel` for thinking-capable models |
 | `toolConfig` | ✅ | `functionCallingConfig.mode`: `AUTO`/`ANY`/`NONE` |
 | SSE streaming | ✅ | Cloud Code API with `streamGenerateContent?alt=sse` |
 | Token refresh | ✅ | Automatic via refresh token |

src/llm/gemini_oauth.rs

@@ -89,7 +89,7 @@ fn default_safety_settings() -> Vec<serde_json::Value> {
 
 /// Parse `GEMINI_CLI_CUSTOM_HEADERS` env var in format `key:value,key:value`.
 /// Commas inside values are preserved — splits only on commas followed by a
-/// valid HTTP header name pattern (ASCII alphanumeric/hyphen, then `:`).
+/// valid HTTP header name pattern (ASCII alphanumeric/hyphen/underscore, then `:`).
 fn parse_custom_headers() -> std::collections::HashMap<String, String> {
     let mut headers = std::collections::HashMap::new();
     let env_val = match std::env::var("GEMINI_CLI_CUSTOM_HEADERS") {
@@ -397,7 +397,9 @@ impl CredentialManager {
                 if let Some(pid) = self.discover_project_id(&updated.access_token).await {
                     info!(project_id = %pid, "Discovered Cloud Code project");
                     updated.project_id = Some(pid);
-                    let _ = self.save_credential(&updated).await;
+                    if let Err(e) = self.save_credential(&updated).await {
+                        warn!(error = %e, "Failed to persist discovered project_id to credentials file");
+                    }
                 }
                 return Ok(updated);
             }
@@ -1617,7 +1619,13 @@ impl GeminiOauthProvider {
                     }));
                 }
                 Role::Assistant => {
-                    let mut parts = vec![serde_json::json!({ "text": msg.content })];
+                    let mut parts = Vec::new();
+                    // Only add text part if content is non-empty (assistant messages
+                    // with tool calls often have empty content, and curate_contents
+                    // would drop the entire turn if it sees an empty text part).
+                    if !msg.content.is_empty() {
+                        parts.push(serde_json::json!({ "text": msg.content }));
+                    }
                     if let Some(ref calls) = msg.tool_calls {
                         for call in calls {
                             parts.push(serde_json::json!({
@@ -1628,6 +1636,11 @@ impl GeminiOauthProvider {
                             }));
                         }
                     }
+                    // Fallback: if no parts at all, add empty text to avoid
+                    // sending a turn with zero parts (API rejects it).
+                    if parts.is_empty() {
+                        parts.push(serde_json::json!({ "text": "" }));
+                    }
                     contents.push(serde_json::json!({
                         "role": "model",
                         "parts": parts
@@ -2080,8 +2093,8 @@ impl LlmProvider for GeminiOauthProvider {
             input_tokens: response.input_tokens,
             output_tokens: response.output_tokens,
             tool_calls,
-            cache_read_input_tokens: 0,
-            cache_creation_input_tokens: 0,
+            cache_read_input_tokens: response.cache_read_input_tokens,
+            cache_creation_input_tokens: response.cache_creation_input_tokens,
         })
     }
 }

src/setup/wizard.rs

@@ -1037,7 +1037,7 @@ impl SetupWizard {
             } else {
                 match current.as_str() {
                     "nearai" => "NEAR AI".to_string(),
-                    "gemini_oauth" => "Gemini API (OAuth)".to_string(),
+                    "gemini_oauth" | "gemini-oauth" => "Gemini API (OAuth)".to_string(),
                     _ => {
                         if let Some(def) = registry.find(&current) {
                             def.setup
@@ -1055,6 +1055,7 @@ impl SetupWizard {
             let is_known = current == "nearai"
                 || current == "bedrock"
                 || current == "gemini_oauth"
+                || current == "gemini-oauth"
                 || registry.is_known(&current);
 
             if is_known && confirm("Keep current provider?", true).map_err(SetupError::Io)? {
@@ -1062,7 +1063,7 @@ impl SetupWizard {
                     print_info("Keeping existing AWS Bedrock configuration.");
                     return Ok(());
                 }
-                if current == "gemini_oauth" {
+                if current == "gemini_oauth" || current == "gemini-oauth" {
                     print_info("Keeping existing Gemini CLI OAuth configuration.");
                     return Ok(());
                 }