From 151293413802a861da066239739ccd5976f97de7 Mon Sep 17 00:00:00 2001
From: nuthalapativarun <nuthalapativarun@gmail.com>
Date: Tue, 16 Jun 2026 11:48:08 -0700
Subject: [PATCH] fix: fall back to default provider when resuming session with
 unavailable provider (#9547)

Signed-off-by: Varun Nuthalapati <nuthalapativarun@gmail.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 crates/goose-cli/src/session/builder.rs | 71 ++++++++++++++++++++++---
 1 file changed, 65 insertions(+), 6 deletions(-)

diff --git a/crates/goose-cli/src/session/builder.rs b/crates/goose-cli/src/session/builder.rs
index a01395208..4ffa84424 100644
--- a/crates/goose-cli/src/session/builder.rs
+++ b/crates/goose-cli/src/session/builder.rs
@@ -531,14 +531,66 @@ pub async fn build_session(session_config: SessionBuilderConfig) -> CliSession {
             }
         };
 
-    let new_provider = match create(
+    let (new_provider, effective_provider_name, effective_model_name) = match create(
         &resolved.provider_name,
-        resolved.model_config,
+        resolved.model_config.clone(),
         extensions_for_provider.clone(),
     )
     .await
     {
-        Ok(provider) => provider,
+        Ok(provider) => (
+            provider,
+            resolved.provider_name.clone(),
+            resolved.model_name.clone(),
+        ),
+        Err(e)
+            if session_config.resume
+                && session_config.provider.is_none()
+                && is_provider_unavailable_error(&e) =>
+        {
+            let fallback_provider = config.get_goose_provider().unwrap_or_else(|_| {
+                output::render_error("No provider configured. Run 'goose configure' first.");
+                process::exit(1);
+            });
+            let fallback_model = config.get_goose_model().unwrap_or_else(|_| {
+                output::render_error("No model configured. Run 'goose configure' first.");
+                process::exit(1);
+            });
+            eprintln!(
+                "{}",
+                style(format!(
+                    "Warning: Could not create the session's original provider '{}' ({}). \
+                    Falling back to the default provider '{}'.",
+                    resolved.provider_name, e, fallback_provider
+                ))
+                .yellow()
+            );
+            let fallback_model_config = goose::model::ModelConfig::new(&fallback_model)
+                .unwrap_or_else(|e| {
+                    output::render_error(&format!("Failed to create model configuration: {}", e));
+                    process::exit(1);
+                })
+                .with_canonical_limits(&fallback_provider);
+            match create(
+                &fallback_provider,
+                fallback_model_config,
+                extensions_for_provider.clone(),
+            )
+            .await
+            {
+                Ok(provider) => (provider, fallback_provider, fallback_model),
+                Err(e2) => {
+                    output::render_error(&format!(
+                        "Error {}.\n\
+                        Please check your system keychain and run 'goose configure' again.\n\
+                        If your system is unable to use the keyring, please try setting secret key(s) via environment variables.\n\
+                        For more info, see: https://goose-docs.ai/docs/troubleshooting/#keychainkeyring-errors",
+                        e2
+                    ));
+                    process::exit(1);
+                }
+            }
+        }
         Err(e) => {
             output::render_error(&format!(
                 "Error {}.\n\
@@ -550,7 +602,7 @@ pub async fn build_session(session_config: SessionBuilderConfig) -> CliSession {
             process::exit(1);
         }
     };
-    tracing::info!("🤖 Using model: {}", resolved.model_name);
+    tracing::info!("🤖 Using model: {}", effective_model_name);
 
     agent
         .update_provider(new_provider, &session_id)
@@ -613,14 +665,21 @@ pub async fn build_session(session_config: SessionBuilderConfig) -> CliSession {
     if !session_config.quiet {
         output::display_session_info(
             session_config.resume,
-            &resolved.provider_name,
-            &resolved.model_name,
+            &effective_provider_name,
+            &effective_model_name,
             &Some(session_id),
         );
     }
     session
 }
 
+fn is_provider_unavailable_error(e: &anyhow::Error) -> bool {
+    let msg = e.to_string();
+    msg.contains("is not set")
+        || msg.contains("not configured")
+        || msg.contains("Configuration value not found")
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;