Files
vikingowl eea26a262e feat(router): surface bandit knobs as [router.bandit] config
Four hardcoded constants in the selector and feedback tracker are now
user-tunable via [router.bandit]:

- quality_alpha    (EMA smoothing, default 0.3)
- min_observations (samples before observed overrides heuristic, default 3)
- observed_weight  (observed/heuristic blend ratio, default 0.7)
- strength_bonus   (quality bonus for Strengths-tagged arms, default 0.15)

Each field treats 0 as 'use default', so an empty TOML block is
byte-identical to pre-config behaviour. BanditParams is plumbed via
router.Config{Bandit: ...} and resolveBanditParams() centralises the
fallback so every call site shares the same defaults.

QualityTracker, scoreArm, bestScored, and selectBest signatures now
take the configured values directly rather than reaching for package-
level constants. Tests updated to pass BanditParams{} (defaults) or
explicit overrides where they validate the new tuning paths.

Tracks item #3 from the 'Bandit selector — design decisions deferred'
TODO entry — ships independently of the EMA vs SLM strategic decision.
2026-05-24 22:42:34 +02:00

158 lines
5.2 KiB
Go

package router_test
import (
"testing"
"somegit.dev/Owlibou/gnoma/internal/provider"
"somegit.dev/Owlibou/gnoma/internal/router"
)
func TestQualityTracker_NoDataReturnsHeuristic(t *testing.T) {
qt := router.NewQualityTracker(0, 0)
_, hasData := qt.Quality("arm:model", router.TaskGeneration)
if hasData {
t.Error("expected no data for unobserved arm")
}
}
func TestQualityTracker_RecordUpdatesEMA(t *testing.T) {
qt := router.NewQualityTracker(0, 0)
for i := 0; i < 3; i++ {
qt.Record("arm:model", router.TaskGeneration, true)
}
score, hasData := qt.Quality("arm:model", router.TaskGeneration)
if !hasData {
t.Fatal("expected data after 3 observations")
}
if score <= 0 || score > 1 {
t.Errorf("score out of range [0,1]: %f", score)
}
}
func TestQualityTracker_AllFailuresLowScore(t *testing.T) {
qt := router.NewQualityTracker(0, 0)
for i := 0; i < 5; i++ {
qt.Record("arm:model", router.TaskDebug, false)
}
score, _ := qt.Quality("arm:model", router.TaskDebug)
if score > 0.3 {
t.Errorf("expected low score after all failures, got %f", score)
}
}
func TestQualityTracker_ConcurrentSafe(t *testing.T) {
qt := router.NewQualityTracker(0, 0)
done := make(chan struct{})
for i := 0; i < 10; i++ {
go func(success bool) {
qt.Record("arm:model", router.TaskReview, success)
done <- struct{}{}
}(i%2 == 0)
}
for i := 0; i < 10; i++ {
<-done
}
score, _ := qt.Quality("arm:model", router.TaskReview)
if score < 0 || score > 1 {
t.Errorf("invalid score after concurrent writes: %f", score)
}
}
func TestQualityTracker_InfluencesArmSelection(t *testing.T) {
// After enough observations, the arm with a higher quality history should
// be preferred by Router.Select() over an identically-heuristic arm.
caps := provider.Capabilities{ToolUse: true}
armA := &router.Arm{ID: "test/arm-a", ModelName: "arm-a", Capabilities: caps}
armB := &router.Arm{ID: "test/arm-b", ModelName: "arm-b", Capabilities: caps}
r := router.New(router.Config{})
r.RegisterArm(armA)
r.RegisterArm(armB)
// Record 5 successes for A, 5 failures for B — enough to exceed minObservations=3.
task := router.Task{Type: router.TaskGeneration, RequiresTools: true, Priority: router.PriorityNormal}
for range 5 {
r.ReportOutcome(router.Outcome{ArmID: "test/arm-a", TaskType: router.TaskGeneration, Success: true})
r.ReportOutcome(router.Outcome{ArmID: "test/arm-b", TaskType: router.TaskGeneration, Success: false})
}
decision := r.Select(task)
if decision.Error != nil {
t.Fatalf("Select: %v", decision.Error)
}
defer decision.Rollback()
if decision.Arm.ID != "test/arm-a" {
t.Errorf("expected arm-a (high quality history) to be selected, got %s", decision.Arm.ID)
}
}
func TestQualityTracker_InsufficientDataFallsBackToHeuristic(t *testing.T) {
// Below minObservations (3), Quality() returns hasData=false and routing
// must still succeed (falls back to heuristic scoring).
caps := provider.Capabilities{ToolUse: true}
arm := &router.Arm{ID: "test/arm-x", ModelName: "arm-x", Capabilities: caps}
r := router.New(router.Config{})
r.RegisterArm(arm)
// Only 1 observation — below the minimum.
r.ReportOutcome(router.Outcome{ArmID: "test/arm-x", TaskType: router.TaskGeneration, Success: true})
qt := r.QualityTracker()
_, hasData := qt.Quality("test/arm-x", router.TaskGeneration)
if hasData {
t.Error("expected no usable data below minObservations")
}
// Router.Select must still succeed despite no quality data.
task := router.Task{Type: router.TaskGeneration, RequiresTools: true}
decision := r.Select(task)
if decision.Error != nil {
t.Errorf("Select should succeed via heuristic fallback: %v", decision.Error)
}
decision.Rollback()
}
func TestQualityTracker_CustomAlphaShortensMemory(t *testing.T) {
// alpha=0.9 weights the latest sample heavily; after a single
// failure the score should drop further than with the default 0.3.
fast := router.NewQualityTracker(0.9, 0)
slow := router.NewQualityTracker(0.0, 0) // 0 → default 0.3
for _, qt := range []*router.QualityTracker{fast, slow} {
// Build up history at the high end with 5 successes.
for i := 0; i < 5; i++ {
qt.Record("arm:m", router.TaskGeneration, true)
}
// One failure.
qt.Record("arm:m", router.TaskGeneration, false)
}
fastScore, _ := fast.Quality("arm:m", router.TaskGeneration)
slowScore, _ := slow.Quality("arm:m", router.TaskGeneration)
if !(fastScore < slowScore) {
t.Errorf("expected fast alpha (0.9) to drop quality faster than default (0.3): fast=%f slow=%f", fastScore, slowScore)
}
}
func TestQualityTracker_CustomMinObservationsGatesScore(t *testing.T) {
// minObs=10 means Quality should return hasData=false until 10
// observations are recorded, even though the default would say
// "yes" after 3.
qt := router.NewQualityTracker(0, 10)
for i := 0; i < 5; i++ {
qt.Record("arm:m", router.TaskGeneration, true)
}
if _, hasData := qt.Quality("arm:m", router.TaskGeneration); hasData {
t.Error("expected hasData=false at 5 observations with minObs=10")
}
for i := 0; i < 5; i++ {
qt.Record("arm:m", router.TaskGeneration, true)
}
if _, hasData := qt.Quality("arm:m", router.TaskGeneration); !hasData {
t.Error("expected hasData=true after 10 observations with minObs=10")
}
}