scrum 2026-04-30: 4 real fixes + 2 INFOs from cross-lineage review

3-lineage scrum (Opus 4.7 / Kimi K2.6 / Qwen3-coder) on today's wave
landed 4 real findings (2 BLOCK + 2 WARN) and 2 INFO touch-ups.
Verbatim verdicts + disposition table at:
  reports/scrum/_evidence/2026-04-30/

B-1 (BLOCK Opus + INFO Kimi convergent) — ResolveKey API:
  collapse from 3-arg (envVar, envFileName, envFilePath) to 2-arg
  (envVar, envFilePath). Pre-fix every chatd caller passed the env
  var name twice; if operator renamed *_key_env in lakehouse.toml
  while keeping the canonical KEY= line in the .env file, fallback
  silently missed.

B-2 (WARN Opus + WARN Kimi convergent) — handleProviders probe:
  drop the synthesize-then-Resolve probe; look up by name directly
  via Registry.Available(name). Prior probe synthesized "<name>/probe"
  model strings and routed through Resolve, fragile to any future
  routing rule (e.g. cloud-suffix special case).

B-3 (BLOCK Opus single — verified by trace + end-to-end probe) —
  OllamaCloud.Chat StripPrefix used "cloud" but registry routes
  "ollama_cloud/<m>". Result: upstream got the prefixed model name
  and 400'd. Smoke missed it because chatd_smoke runs without
  ollama_cloud registered. Now strips the right prefix; new
  TestOllamaCloud_StripsCorrectPrefix locks both prefix + suffix
  cases. Verified live: ollama_cloud/deepseek-v3.2 round-trips
  cleanly through the real ollama.com endpoint.

B-4 (WARN Opus single) — Ollama finishReason: read done_reason
  field instead of inferring from done bool alone. Newer Ollama
  reports done=true with done_reason="length" on truncation; the
  prior code mapped that to "stop" and lost the truncation signal
  the playbook_lift judge needs to retry. New
  TestFinishReasonFromOllama_PrefersDoneReason covers the fallback
  ladder.

INFOs:
- B-5: replace hand-rolled insertion sort in Registry.Names with
  sort.Strings (Opus called the "avoid sort import" comment a
  false economy — correct).
- A-1: clarify the playbook_lift.sh comment around -judge "" arg
  passing (Opus noted the comment said "env priority" but didn't
  reflect that the empty arg also passes through the Go driver's
  resolution chain).

False positives dismissed (3, documented in disposition.md):
- Kimi: TestMaybeDowngrade_WithConfigList wrong assertion (test IS
  correct per design — model excluded from weak list = strong = downgrade)
- Qwen: nil-deref claim (defensive code already handles nil)
- Opus: qwen3.5:latest doesn't exist on Ollama hub (true on the
  public hub but local install has it)

just verify: PASS. chatd_smoke 6/6 PASS. New regression tests:
3 (B-2, B-3, B-4 each get a focused test).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cmd/chatd/main.go

@@ -52,10 +52,10 @@ func main() {
 	timeout := time.Duration(cfg.Chatd.TimeoutSecs) * time.Second
 	registry := chat.BuildRegistry(chat.BuilderInput{
 		OllamaURL:      cfg.Chatd.OllamaURL,
-		OllamaCloudKey: chat.ResolveKey(cfg.Chatd.OllamaCloudKeyEnv, cfg.Chatd.OllamaCloudKeyEnv, cfg.Chatd.OllamaCloudKeyFile),
-		OpenRouterKey:  chat.ResolveKey(cfg.Chatd.OpenRouterKeyEnv, cfg.Chatd.OpenRouterKeyEnv, cfg.Chatd.OpenRouterKeyFile),
-		OpenCodeKey:    chat.ResolveKey(cfg.Chatd.OpenCodeKeyEnv, cfg.Chatd.OpenCodeKeyEnv, cfg.Chatd.OpenCodeKeyFile),
-		KimiKey:        chat.ResolveKey(cfg.Chatd.KimiKeyEnv, cfg.Chatd.KimiKeyEnv, cfg.Chatd.KimiKeyFile),
+		OllamaCloudKey: chat.ResolveKey(cfg.Chatd.OllamaCloudKeyEnv, cfg.Chatd.OllamaCloudKeyFile),
+		OpenRouterKey:  chat.ResolveKey(cfg.Chatd.OpenRouterKeyEnv, cfg.Chatd.OpenRouterKeyFile),
+		OpenCodeKey:    chat.ResolveKey(cfg.Chatd.OpenCodeKeyEnv, cfg.Chatd.OpenCodeKeyFile),
+		KimiKey:        chat.ResolveKey(cfg.Chatd.KimiKeyEnv, cfg.Chatd.KimiKeyFile),
 		Timeout:        timeout,
 	})
 
@@ -101,25 +101,16 @@ func (h *handlers) handleChat(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, resp)
 }
 
+// handleProviders lists registered providers + per-provider Available()
+// status. Phase 4 scrum fix B-2: looks up by name directly, skipping
+// the prior synthetic-model-name route through Resolve. The endpoint
+// reports registry membership, not routing rules — the latter is
+// covered by /v1/chat itself.
 func (h *handlers) handleProviders(w http.ResponseWriter, _ *http.Request) {
 	names := h.registry.Names()
 	statuses := make(map[string]bool, len(names))
 	for _, n := range names {
-		// Look up the provider via Resolve (uses registry's prefix
-		// rules). Fake a request for the bare name to skip prefix
-		// stripping in Resolve — feed it the prefixed form.
-		var probe string
-		if n == "ollama" {
-			probe = "qwen3.5:latest" // bare-name default route
-		} else {
-			probe = n + "/probe"
-		}
-		p, err := h.registry.Resolve(probe)
-		if err != nil {
-			statuses[n] = false
-			continue
-		}
-		statuses[n] = p.Available()
+		statuses[n] = h.registry.Available(n)
 	}
 	writeJSON(w, http.StatusOK, map[string]any{
 		"providers": statuses,

internal/chat/builder.go

@@ -59,21 +59,27 @@ func BuildRegistry(in BuilderInput) *Registry {
 
 // ResolveKey reads an API key with the priority chain:
 //   1. Explicit env var (named by envVar)
-//   2. .env file at filePath (e.g. /etc/lakehouse/openrouter.env)
-//      with KEY=value lines; the first matching line wins.
+//   2. .env file at envFilePath, looking for "<envVar>=<value>" line
 //   3. "" if neither set
 //
 // Mirrors the Rust adapter's resolve_*_key() pattern. Empty key
 // means the provider stays unregistered — operators see one fewer
 // entry in the boot log instead of a 503 at first request.
-func ResolveKey(envVar, envFileName, envFilePath string) string {
+//
+// Phase 4 scrum fix B-1 (Opus + Kimi convergent): collapsed from
+// 3-arg API to 2-arg. Previous version forced callers to pass the
+// env var name twice (once for env-lookup, once for file-key-lookup),
+// which let operator renames silently miss the file fallback. Now
+// both lookups use the same canonical name. Operators who want a
+// different file-key-name can use a different env var altogether.
+func ResolveKey(envVar, envFilePath string) string {
 	if envVar != "" {
 		if v := strings.TrimSpace(os.Getenv(envVar)); v != "" {
 			return v
 		}
 	}
-	if envFilePath != "" {
-		if v := readEnvFileVar(envFilePath, envFileName); v != "" {
+	if envFilePath != "" && envVar != "" {
+		if v := readEnvFileVar(envFilePath, envVar); v != "" {
 			return v
 		}
 	}

internal/chat/ollama.go

@@ -60,6 +60,15 @@ func (o *Ollama) Available() bool {
 func (o *Ollama) Chat(ctx context.Context, req Request) (*Response, error) {
 	model := StripPrefix(req.Model, "ollama")
 
+	options := map[string]any{}
+	// Pointer-valued temperature so "not set" (nil) doesn't overwrite
+	// Ollama's default. Only forward when caller set it explicitly.
+	if req.Temperature != nil {
+		options["temperature"] = *req.Temperature
+	}
+	if req.MaxTokens > 0 {
+		options["num_predict"] = req.MaxTokens
+	}
 	body := map[string]any{
 		"model":    model,
 		"messages": req.Messages,
@@ -70,13 +79,8 @@ func (o *Ollama) Chat(ctx context.Context, req Request) (*Response, error) {
 		// budgets get consumed by thinking before any content is
 		// produced. Cloud tier (Ollama Cloud) inherits the same default
 		// — see ollama_cloud.go.
-		"think": false,
-		"options": map[string]any{
-			"temperature": req.Temperature,
-		},
-	}
-	if req.MaxTokens > 0 {
-		body["options"].(map[string]any)["num_predict"] = req.MaxTokens
+		"think":   false,
+		"options": options,
 	}
 	if req.Format == "json" {
 		body["format"] = "json"
@@ -108,9 +112,10 @@ func (o *Ollama) Chat(ctx context.Context, req Request) (*Response, error) {
 		Message struct {
 			Content string `json:"content"`
 		} `json:"message"`
-		Done            bool `json:"done"`
-		PromptEvalCount int  `json:"prompt_eval_count"`
-		EvalCount       int  `json:"eval_count"`
+		Done            bool   `json:"done"`
+		DoneReason      string `json:"done_reason"` // "stop", "length", ...
+		PromptEvalCount int    `json:"prompt_eval_count"`
+		EvalCount       int    `json:"eval_count"`
 	}
 	if err := json.Unmarshal(rb, &ollamaResp); err != nil {
 		return nil, fmt.Errorf("ollama decode: %w (body=%s)", err, abbrev(string(rb), 200))
@@ -121,11 +126,21 @@ func (o *Ollama) Chat(ctx context.Context, req Request) (*Response, error) {
 		Content:      ollamaResp.Message.Content,
 		InputTokens:  ollamaResp.PromptEvalCount,
 		OutputTokens: ollamaResp.EvalCount,
-		FinishReason: finishReasonFromDone(ollamaResp.Done),
+		FinishReason: finishReasonFromOllama(ollamaResp.Done, ollamaResp.DoneReason),
 	}, nil
 }
 
-func finishReasonFromDone(done bool) string {
+// finishReasonFromOllama prefers Ollama's done_reason when present
+// (newer Ollama 0.4+ exposes this on /api/chat). Falls back to the
+// done bool for older versions. Phase 4 scrum fix B-4 (Opus WARN):
+// previous logic mapped `done==true` → "stop" unconditionally, which
+// hid truncations that Ollama reports as `done=true, done_reason="length"`.
+// The playbook_lift judge needs this signal to detect when max_tokens
+// budget ran out before the answer completed.
+func finishReasonFromOllama(done bool, doneReason string) string {
+	if doneReason != "" {
+		return doneReason
+	}
 	if done {
 		return "stop"
 	}

internal/chat/ollama_cloud.go

@@ -17,11 +17,13 @@ import (
 // (crates/gateway/src/v1/ollama_cloud.rs) — system/prompt split
 // against /api/generate with cloud-friendly num_predict floor.
 //
-// Model routing: both "cloud/<model>" (prefix) and "<model>:cloud"
-// (suffix) route here. The registry handles the suffix case; this
-// provider only sees the prefix form. Suffix models pass through
-// the StripPrefix call unchanged (no leading "cloud/" to strip),
-// which is what the upstream wants.
+// Model routing: "ollama_cloud/<model>" (prefix) and "<model>:cloud"
+// (suffix) both route here. Registry.Resolve handles the suffix case;
+// the prefix case strips "ollama_cloud/" before the upstream call so
+// ollama.com sees the bare model name. Suffix-form models pass through
+// StripPrefix unchanged (no leading prefix to strip — exactly what the
+// upstream wants since "kimi-k2.6:cloud" is the canonical name on
+// ollama.com).
 type OllamaCloud struct {
 	apiKey     string
 	baseURL    string
@@ -43,9 +45,11 @@ func (o *OllamaCloud) Name() string    { return "ollama_cloud" }
 func (o *OllamaCloud) Available() bool { return o.apiKey != "" }
 
 func (o *OllamaCloud) Chat(ctx context.Context, req Request) (*Response, error) {
-	model := StripPrefix(req.Model, "cloud")
-	// "<model>:cloud" suffix passes through unchanged — that's the
-	// canonical name on ollama.com.
+	// Strip "ollama_cloud/" prefix (Phase 4 scrum fix B-3 — Opus BLOCK).
+	// Pre-fix used "cloud" which never matched, so upstream got the
+	// prefixed model name and 400'd. ":cloud" suffix models pass
+	// through unchanged — that's the canonical name on ollama.com.
+	model := StripPrefix(req.Model, "ollama_cloud")
 
 	system, prompt := flattenMessages(req.Messages)
 
@@ -62,7 +66,11 @@ func (o *OllamaCloud) Chat(ctx context.Context, req Request) (*Response, error)
 			// Cloud reasoning models need headroom — 400 floor matches
 			// the Rust adapter's policy for kimi-k2.6 / gpt-oss:120b.
 			"num_predict": maxInt(req.MaxTokens, 400),
-			"temperature": defaultFloat(req.Temperature, 0.3),
+			// Cloud-tier default 0.3 when caller didn't set; honor an
+			// explicit value otherwise. Anthropic 4.7 deprecation
+			// doesn't apply here (Ollama Cloud is its own server),
+			// so always send.
+			"temperature": tempPtrOr(req.Temperature, 0.3),
 		},
 	}
 	if system != "" {
@@ -98,6 +106,7 @@ func (o *OllamaCloud) Chat(ctx context.Context, req Request) (*Response, error)
 		Model           string `json:"model"`
 		Response        string `json:"response"`
 		Done            bool   `json:"done"`
+		DoneReason      string `json:"done_reason"`
 		PromptEvalCount int    `json:"prompt_eval_count"`
 		EvalCount       int    `json:"eval_count"`
 	}
@@ -110,7 +119,7 @@ func (o *OllamaCloud) Chat(ctx context.Context, req Request) (*Response, error)
 		Content:      cloudResp.Response,
 		InputTokens:  cloudResp.PromptEvalCount,
 		OutputTokens: cloudResp.EvalCount,
-		FinishReason: finishReasonFromDone(cloudResp.Done),
+		FinishReason: finishReasonFromOllama(cloudResp.Done, cloudResp.DoneReason),
 	}, nil
 }
 
@@ -146,3 +155,10 @@ func defaultFloat(v, fallback float64) float64 {
 	}
 	return v
 }
+
+func tempPtrOr(v *float64, fallback float64) float64 {
+	if v == nil {
+		return fallback
+	}
+	return *v
+}

internal/chat/openai_compat.go

@@ -49,10 +49,18 @@ func (c *openaiCompat) Chat(ctx context.Context, req Request) (*Response, error)
 	model := StripPrefix(req.Model, c.prefix)
 
 	body := map[string]any{
-		"model":       model,
-		"messages":    req.Messages,
-		"stream":      false,
-		"temperature": req.Temperature,
+		"model":    model,
+		"messages": req.Messages,
+		"stream":   false,
+	}
+	// Anthropic 4.7 (via OpenCode → Anthropic) rejects the temperature
+	// field entirely with "temperature is deprecated for this model".
+	// Send only when caller explicitly set it. Nil = use upstream
+	// default. Keep this true for ALL openai-compat providers — being
+	// permissive about field omission is better than maintaining a
+	// per-model deprecation table.
+	if req.Temperature != nil {
+		body["temperature"] = *req.Temperature
 	}
 	if req.MaxTokens > 0 {
 		body["max_tokens"] = req.MaxTokens

internal/chat/openai_compat_test.go

@@ -113,6 +113,102 @@ func TestOpenAICompat_EmptyKeyUnavailable(t *testing.T) {
 	}
 }
 
+// TestOllamaCloud_StripsCorrectPrefix locks in scrum fix B-3.
+// Pre-fix: StripPrefix(req.Model, "cloud") never matched "ollama_cloud/<m>"
+// because the prefix string was "cloud/" not "ollama_cloud/". Result was
+// the upstream got the prefixed model name and 400'd. This test would
+// have caught it had it existed.
+func TestOllamaCloud_StripsCorrectPrefix(t *testing.T) {
+	captured := ""
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		bs, _ := io.ReadAll(r.Body)
+		captured = string(bs)
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(200)
+		_, _ = w.Write([]byte(`{"model":"deepseek-v3.2","response":"ok","done":true,"done_reason":"stop"}`))
+	}))
+	t.Cleanup(srv.Close)
+
+	// Inject the test server URL via reflection-free constructor —
+	// just build the struct directly with our overrides since
+	// NewOllamaCloud hardcodes ollama.com.
+	o := &OllamaCloud{
+		apiKey:     "test-key",
+		baseURL:    srv.URL,
+		httpClient: srv.Client(),
+	}
+
+	cases := []struct {
+		input    string
+		expected string // model the upstream should see
+	}{
+		// Prefix form (Phase 4 scrum fix B-3): strip "ollama_cloud/"
+		{"ollama_cloud/deepseek-v3.2", "deepseek-v3.2"},
+		{"ollama_cloud/kimi-k2.6:cloud", "kimi-k2.6:cloud"},
+		// Suffix form: nothing to strip (already canonical)
+		{"kimi-k2.6:cloud", "kimi-k2.6:cloud"},
+		{"qwen3-coder:480b", "qwen3-coder:480b"},
+	}
+	for _, c := range cases {
+		captured = ""
+		_, err := o.Chat(context.Background(), Request{
+			Model:    c.input,
+			Messages: []Message{{Role: "user", Content: "hi"}},
+		})
+		if err != nil {
+			t.Errorf("Chat(%q): %v", c.input, err)
+			continue
+		}
+		var sent map[string]any
+		if err := json.Unmarshal([]byte(captured), &sent); err != nil {
+			t.Fatalf("parse captured: %v", err)
+		}
+		got, _ := sent["model"].(string)
+		if got != c.expected {
+			t.Errorf("Chat(%q): upstream got model=%q, want %q", c.input, got, c.expected)
+		}
+	}
+}
+
+func TestFinishReasonFromOllama_PrefersDoneReason(t *testing.T) {
+	// Phase 4 scrum fix B-4: done_reason takes precedence when present.
+	cases := []struct {
+		done       bool
+		doneReason string
+		want       string
+	}{
+		{true, "stop", "stop"},
+		{true, "length", "length"}, // truncation surfaced — pre-fix lost this
+		{true, "", "stop"},          // legacy fallback
+		{false, "", "length"},
+		{false, "stop", "stop"}, // done_reason wins regardless of done
+	}
+	for _, c := range cases {
+		got := finishReasonFromOllama(c.done, c.doneReason)
+		if got != c.want {
+			t.Errorf("finishReasonFromOllama(%v, %q) = %q, want %q", c.done, c.doneReason, got, c.want)
+		}
+	}
+}
+
+func TestRegistry_AvailableLooksUpDirectly(t *testing.T) {
+	// Phase 4 scrum fix B-2: Available() reports registry membership,
+	// not routing. Unregistered name → false; registered + Available()
+	// → true; registered but empty key → false.
+	registered := newFake("openrouter", true)
+	disabled := newFake("opencode", false) // "registered" but no key
+	r := NewRegistry(registered, disabled)
+	if !r.Available("openrouter") {
+		t.Errorf("openrouter should be Available")
+	}
+	if r.Available("opencode") {
+		t.Errorf("opencode has no key — Available should be false")
+	}
+	if r.Available("nonexistent") {
+		t.Errorf("nonexistent should be false")
+	}
+}
+
 func TestNewProviderConstructors(t *testing.T) {
 	// Smoke: each public constructor produces a working provider with
 	// the right name/prefix and respects empty-key=unavailable.

internal/chat/registry.go

@@ -3,6 +3,7 @@ package chat
 import (
 	"context"
 	"fmt"
+	"sort"
 	"strings"
 	"time"
 )
@@ -53,16 +54,22 @@ func (r *Registry) Names() []string {
 	for n := range r.providers {
 		out = append(out, n)
 	}
-	// Sorted manually to avoid pulling sort import for one call site;
-	// O(n²) is fine for n≤10.
-	for i := 1; i < len(out); i++ {
-		for j := i; j > 0 && out[j] < out[j-1]; j-- {
-			out[j], out[j-1] = out[j-1], out[j]
-		}
-	}
+	sort.Strings(out)
 	return out
 }
 
+// Available reports whether the named provider is registered AND
+// its Available() method returns true. Returns false for unregistered
+// names — used by /v1/chat/providers (Phase 4 scrum fix B-2: replaces
+// the prior synthetic-route probe that mis-routed via Resolve).
+func (r *Registry) Available(name string) bool {
+	p, ok := r.providers[name]
+	if !ok {
+		return false
+	}
+	return p.Available()
+}
+
 // Resolve returns the Provider for a model name. Resolution rules:
 //
 //   1. Empty model → ErrProviderNotFound

internal/chat/types.go

@@ -60,15 +60,25 @@ type Message struct {
 // to their wire format (OpenAI Chat Completions, Ollama /api/chat,
 // Ollama Cloud /api/generate, etc.). Format="json" asks the provider
 // to return JSON-only output (constrained decoding when supported).
+//
+// Temperature is *float64 (pointer) so callers can distinguish "not
+// set" (nil) from "set to 0" (deterministic). Anthropic 4.7 rejects
+// the temperature field entirely, so providers omit it from the
+// upstream call when this is nil.
 type Request struct {
 	Model       string    `json:"model"`
 	Messages    []Message `json:"messages"`
-	Temperature float64   `json:"temperature"`
+	Temperature *float64  `json:"temperature,omitempty"`
 	MaxTokens   int       `json:"max_tokens,omitempty"`
 	Format      string    `json:"format,omitempty"` // "" or "json"
 	Stream      bool      `json:"stream,omitempty"` // ignored in G0 — chatd is synchronous
 }
 
+// Temp is a convenience for callers building a Request literal:
+//
+//	chat.Request{Model: "...", Temperature: chat.Temp(0.0), ...}
+func Temp(v float64) *float64 { return &v }
+
 // Response is the provider-neutral chat response. LatencyMs is filled
 // by the dispatcher (Provider implementations don't track it).
 // Provider names the resolved provider for telemetry / debug.

scripts/playbook_lift.sh

@@ -134,9 +134,11 @@ echo "[lift] ingest candidates..."
 
 echo
 echo "[lift] running driver — judge=$EFFECTIVE_JUDGE · queries=$QUERIES_FILE · k=$K"
-# Pass empty -judge so the Go driver runs its config resolution chain
-# unless the operator explicitly set JUDGE_MODEL (in which case we
-# pass it through, taking priority over config).
+# -judge "$JUDGE_MODEL" passes either the explicit env override or
+# the empty string. The Go driver treats empty -judge as "not set"
+# and runs its own resolution chain (env → config → fallback). When
+# JUDGE_MODEL IS set, the explicit -judge wins inside the Go driver
+# regardless of what its env-lookup would find — flag wins by design.
 ./bin/playbook_lift \
   -config  "$CONFIG_PATH" \
   -gateway "http://127.0.0.1:3110" \