opencode: option to override model used by specialized (sub)agents

Author: YPares

lib/mkRiglib.nix

@@ -19,7 +19,7 @@ let
       );
   };
 
-  # Override a derivation so its always built locally, and not queried from remote substituters
+  # Override a derivation so it is always built locally, and not queried from remote substituters
   alwaysLocal =
     x:
     if pkgs.lib.isDerivation x then

riglets/models.nix

@@ -1,18 +1,27 @@
 _:
 { lib, ... }:
+let
+  providerAndModel = with lib.types; {
+    providerId = lib.mkOption {
+      type = nullOr str;
+      description = "Model provider ID. Can be ignored depending on the entrypoint";
+      default = null;
+    };
+    modelId = lib.mkOption {
+      type = nullOr str;
+      description = "Model ID";
+      default = null;
+    };
+  };
+in
 {
   options.models = with lib.types; {
-    default = {
-      providerId = lib.mkOption {
-        type = nullOr str;
-        description = "Model provider ID. Can be ignored depending on the entrypoint";
-        default = null;
-      };
-      modelId = lib.mkOption {
-        type = nullOr str;
-        description = "Model ID";
-        default = null;
-      };
+    default = providerAndModel;
+
+    specialized = lib.mkOption {
+      type = types.attrsOf (types.submodule { options = providerAndModel; });
+      description = "Model overrides for specialized agents (plan, build, explore, etc.). Support depends on entrypoint";
+      default = { };
     };
 
     providers = {
@@ -31,7 +40,7 @@ _:
   };
 
   config.riglets.models.meta = {
-    description = "Pre-select a specific model for a rig (to be imported by compatible entrypoints)";
+    description = "Pre-select model(s) for a rig (to be imported by compatible entrypoints)";
     status = "stable";
     version = "0.1.0";
     intent = "base";

riglets/opencode.nix

@@ -32,6 +32,15 @@ in
     let
       manifestPath = rig.manifest.override { shownDocRoot = "$RIG_DOCS"; };
 
+      toModelId =
+        x:
+        if x.modelId != null && x.providerId == null then
+          throw ''
+            If modelId is set, then providerId must be set too
+          ''
+        else
+          "${x.providerId}/${x.modelId}";
+
       # OpenCode config with permissions and MCP servers
       opencodeConfigJson = riglib.toJSON (
         {
@@ -106,30 +115,23 @@ in
           ) (lib.concatMapAttrs (k: v: { "rig:${k}" = v; }) rig.promptCommands);
         }
         // lib.optionalAttrs (config.models.default.modelId != null) {
-          model =
-            if config.models.default.providerId == null then
-              throw ''
-                If models.default.modelId is set, then models.default.providerId must be too
-              ''
-            else
-              "${config.models.default.providerId}/${config.models.default.modelId}";
+          model = toModelId config.models.default;
         }
         // lib.optionalAttrs (config.models.providers.disabled != null) {
           disabled_providers = config.models.providers.disabled;
         }
         // lib.optionalAttrs (config.models.providers.enabled != null) {
           enabled_providers = config.models.providers.enabled;
         }
+        // lib.optionalAttrs (config.models.specialized != { }) {
+          agent = lib.mapAttrs (_agentName: mdl: { model = toModelId mdl; }) config.models.specialized;
+        }
       );
     in
     # Return a folder derivation with bin/ subfolder
     pkgs.writeShellScriptBin "opencode" ''
       set -euo pipefail
 
-      warn() {
-        printf "\033[0;33m%s\n\033[0m" "$1" >&2
-      }
-
       export PATH="${rig.toolRoot}/bin:$PATH"
       export RIG_DOCS="${rig.docRoot}"
       # Exported for convenience

rigup.toml

@@ -60,8 +60,9 @@ extends.self = "example-rig-claude"
 [rigs.example-rig-opencode]
 extends.self = "example-rig"
 riglets.self = ["opencode"]
-config.models.default.providerId = "opencode"
-config.models.default.modelId = "glm-4.7-free"
+config.models.default = { providerId = "opencode", modelId = "glm-4.7" }
+config.models.specialized.plan = { providerId = "opencode", modelId = "claude-opus-4-6" }
+config.models.specialized.explore = { providerId = "opencode", modelId = "kimi-k2.5-free" }
 
 [rigs.example-rig-opencode.config.agent.personality]
 inspiration = "Fa Mulan"
@@ -88,8 +89,8 @@ extends.self = "example-rig"
 riglets.self = ["cursor"]
 config.models.default.modelId = "opus-4.5"
 # config.cursor.justSetupProject = true
-  # If true, the entrypoiny will not start cursor-agent:
-  # it will only setup the .cursor/ folder in the CWD, to be used by Cursor IDE.
+# If true, the entrypoiny will not start cursor-agent:
+# it will only setup the .cursor/ folder in the CWD, to be used by Cursor IDE.
 
 [rigs.example-rig-cursor.config.agent.personality]
 inspiration = "Sauron"