diff --git a/pkg/config/config.go b/pkg/config/config.go
index c4c175495..af2acb726 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -167,19 +167,32 @@ type SessionConfig struct {
 	IdentityLinks map[string][]string `json:"identity_links,omitempty"`
 }
 
+// RoutingConfig controls the intelligent model routing feature.
+// When enabled, each incoming message is scored against structural features
+// (message length, code blocks, tool call history, conversation depth, attachments).
+// Messages scoring below Threshold are sent to LightModel; all others use the
+// agent's primary model. This reduces cost and latency for simple tasks without
+// requiring any keyword matching — all scoring is language-agnostic.
+type RoutingConfig struct {
+	Enabled    bool    `json:"enabled"`
+	LightModel string  `json:"light_model"` // model_name from model_list to use for simple tasks
+	Threshold  float64 `json:"threshold"`   // complexity score in [0,1]; score >= threshold → primary model
+}
+
 type AgentDefaults struct {
-	Workspace                 string   `json:"workspace"                       env:"PICOCLAW_AGENTS_DEFAULTS_WORKSPACE"`
-	RestrictToWorkspace       bool     `json:"restrict_to_workspace"           env:"PICOCLAW_AGENTS_DEFAULTS_RESTRICT_TO_WORKSPACE"`
-	AllowReadOutsideWorkspace bool     `json:"allow_read_outside_workspace"    env:"PICOCLAW_AGENTS_DEFAULTS_ALLOW_READ_OUTSIDE_WORKSPACE"`
-	Provider                  string   `json:"provider"                        env:"PICOCLAW_AGENTS_DEFAULTS_PROVIDER"`
-	ModelName                 string   `json:"model_name,omitempty"            env:"PICOCLAW_AGENTS_DEFAULTS_MODEL_NAME"`
-	Model                     string   `json:"model"                           env:"PICOCLAW_AGENTS_DEFAULTS_MODEL"` // Deprecated: use model_name instead
-	ModelFallbacks            []string `json:"model_fallbacks,omitempty"`
-	ImageModel                string   `json:"image_model,omitempty"           env:"PICOCLAW_AGENTS_DEFAULTS_IMAGE_MODEL"`
-	ImageModelFallbacks       []string `json:"image_model_fallbacks,omitempty"`
-	MaxTokens                 int      `json:"max_tokens"                      env:"PICOCLAW_AGENTS_DEFAULTS_MAX_TOKENS"`
-	Temperature               *float64 `json:"temperature,omitempty"           env:"PICOCLAW_AGENTS_DEFAULTS_TEMPERATURE"`
-	MaxToolIterations         int      `json:"max_tool_iterations"             env:"PICOCLAW_AGENTS_DEFAULTS_MAX_TOOL_ITERATIONS"`
+	Workspace                 string         `json:"workspace"                       env:"PICOCLAW_AGENTS_DEFAULTS_WORKSPACE"`
+	RestrictToWorkspace       bool           `json:"restrict_to_workspace"           env:"PICOCLAW_AGENTS_DEFAULTS_RESTRICT_TO_WORKSPACE"`
+	AllowReadOutsideWorkspace bool           `json:"allow_read_outside_workspace"    env:"PICOCLAW_AGENTS_DEFAULTS_ALLOW_READ_OUTSIDE_WORKSPACE"`
+	Provider                  string         `json:"provider"                        env:"PICOCLAW_AGENTS_DEFAULTS_PROVIDER"`
+	ModelName                 string         `json:"model_name,omitempty"            env:"PICOCLAW_AGENTS_DEFAULTS_MODEL_NAME"`
+	Model                     string         `json:"model"                           env:"PICOCLAW_AGENTS_DEFAULTS_MODEL"` // Deprecated: use model_name instead
+	ModelFallbacks            []string       `json:"model_fallbacks,omitempty"`
+	ImageModel                string         `json:"image_model,omitempty"           env:"PICOCLAW_AGENTS_DEFAULTS_IMAGE_MODEL"`
+	ImageModelFallbacks       []string       `json:"image_model_fallbacks,omitempty"`
+	MaxTokens                 int            `json:"max_tokens"                      env:"PICOCLAW_AGENTS_DEFAULTS_MAX_TOKENS"`
+	Temperature               *float64       `json:"temperature,omitempty"           env:"PICOCLAW_AGENTS_DEFAULTS_TEMPERATURE"`
+	MaxToolIterations         int            `json:"max_tool_iterations"             env:"PICOCLAW_AGENTS_DEFAULTS_MAX_TOOL_ITERATIONS"`
+	Routing                   *RoutingConfig `json:"routing,omitempty"`
 }
 
 // GetModelName returns the effective model name for the agent defaults.