feat: Add exp model to experiment with the tools (#7115)

codex-rs/core/src/model_family.rs

@@ -173,6 +173,19 @@ pub fn find_family_for_model(slug: &str) -> Option<ModelFamily> {
             support_verbosity: true,
             truncation_policy: TruncationPolicy::Tokens(10_000),
         )
+    } else if slug.starts_with("exp-") {
+        model_family!(
+            slug, slug,
+            supports_reasoning_summaries: true,
+            apply_patch_tool_type: Some(ApplyPatchToolType::Freeform),
+            support_verbosity: true,
+            default_verbosity: Some(Verbosity::Low),
+            base_instructions: BASE_INSTRUCTIONS.to_string(),
+            default_reasoning_effort: Some(ReasoningEffort::Medium),
+            truncation_policy: TruncationPolicy::Bytes(10_000),
+            shell_type: ConfigShellToolType::ShellCommand,
+            supports_parallel_tool_calls: true,
+        )
 
     // Production models.
     } else if slug.starts_with("gpt-5.1-codex-max") {