Use Canonical Models to set context window sizes (#6723)

crates/goose/src/agents/agent.rs

@@ -1629,6 +1629,7 @@ impl Agent {
                     .ok_or_else(|| anyhow!("Could not configure agent: missing model"))?;
                 crate::model::ModelConfig::new(&model_name)
                     .map_err(|e| anyhow!("Could not configure agent: invalid model {}", e))?
+                    .with_canonical_limits(&provider_name)
             }
         };
 

crates/goose/src/agents/platform_extensions/summon.rs

@@ -1417,11 +1417,10 @@ impl SummonClient {
             .or_else(|| session.provider_name.clone())
             .ok_or_else(|| anyhow::anyhow!("No provider configured"))?;
 
-        let mut model_config = session
-            .model_config
-            .clone()
-            .map(Ok)
-            .unwrap_or_else(|| crate::model::ModelConfig::new("default"))?;
+        let mut model_config = session.model_config.clone().map(Ok).unwrap_or_else(|| {
+            crate::model::ModelConfig::new("default")
+                .map(|c| c.with_canonical_limits(&provider_name))
+        })?;
 
         if let Some(model) = &params.model {
             model_config.model_name = model.clone();