Merge pull request #11973 from ollama/drifkin/bpe

model: fix boundary in bpe

README.md

@@ -411,6 +411,8 @@ See the [API documentation](./docs/api.md) for all endpoints.
 - [ollama launcher](https://github.com/NGC13009/ollama-launcher) (A launcher for Ollama, aiming to provide users with convenient functions such as ollama server launching, management, or configuration.)
 - [ai-hub](https://github.com/Aj-Seven/ai-hub) (AI Hub supports multiple models via API keys and Chat support via Ollama API.)
 - [Mayan EDMS](https://gitlab.com/mayan-edms/mayan-edms) (Open source document management system to organize, tag, search, and automate your files with powerful Ollama driven workflows.)
+- [Serene Pub](https://github.com/doolijb/serene-pub) (Beginner friendly, open source AI Roleplaying App for Windows, Mac OS and Linux. Search, download and use models with Ollama all inside the app.)
+- [Andes](https://github.com/aqerd/andes) (A Visual Studio Code extension that provides a local UI interface for Ollama models)
 
 ### Cloud
 
@@ -537,6 +539,8 @@ See the [API documentation](./docs/api.md) for all endpoints.
 - [Nichey](https://github.com/goodreasonai/nichey) is a Python package for generating custom wikis for your research topic
 - [Ollama for D](https://github.com/kassane/ollama-d)
 - [OllamaPlusPlus](https://github.com/HardCodeDev777/OllamaPlusPlus) (Very simple C++ library for Ollama)
+- [any-llm](https://github.com/mozilla-ai/any-llm) (A single interface to use different llm providers by [mozilla.ai](https://www.mozilla.ai/))
+- [any-agent](https://github.com/mozilla-ai/any-agent) (A single interface to use and evaluate different agent frameworks by [mozilla.ai](https://www.mozilla.ai/))
 
 ### Mobile
 

api/types.go

@@ -90,6 +90,10 @@ type GenerateRequest struct {
 	// (request that thinking _not_ be used) and unset (use the old behavior
 	// before this option was introduced)
 	Think *ThinkValue `json:"think,omitempty"`
+
+	// DebugRenderOnly is a debug option that, when set to true, returns the rendered
+	// template instead of calling the model.
+	DebugRenderOnly bool `json:"_debug_render_only,omitempty"`
 }
 
 // ChatRequest describes a request sent by [Client.Chat].
@@ -120,6 +124,10 @@ type ChatRequest struct {
 	// responding. Can be a boolean (true/false) or a string ("high", "medium", "low")
 	// for supported models.
 	Think *ThinkValue `json:"think,omitempty"`
+
+	// DebugRenderOnly is a debug option that, when set to true, returns the rendered
+	// template instead of calling the model.
+	DebugRenderOnly bool `json:"_debug_render_only,omitempty"`
 }
 
 type Tools []Tool
@@ -308,6 +316,19 @@ type ChatResponse struct {
 	Metrics
 }
 
+// DebugInfo contains debug information for template rendering
+type DebugInfo struct {
+	RenderedTemplate string `json:"rendered_template"`
+	ImageCount       int    `json:"image_count,omitempty"`
+}
+
+// DebugTemplateResponse is returned when _debug_render_only is set to true
+type DebugTemplateResponse struct {
+	Model     string    `json:"model"`
+	CreatedAt time.Time `json:"created_at"`
+	DebugInfo DebugInfo `json:"_debug_info"`
+}
+
 type Metrics struct {
 	TotalDuration      time.Duration `json:"total_duration,omitempty"`
 	LoadDuration       time.Duration `json:"load_duration,omitempty"`

kvcache/causal.go

@@ -378,9 +378,7 @@ func (c *Causal) buildMask(ctx ml.Context) ml.Tensor {
 	maskTensor := ctx.Input().FromFloatSlice(mask, length, batchSize)
 
 	if c.config.MaskDType != ml.DTypeF32 {
-		out := ctx.Input().Empty(c.config.MaskDType, maskTensor.Shape()...)
-		ctx.Forward(maskTensor.Copy(ctx, out))
-		maskTensor = out
+		maskTensor = maskTensor.Cast(ctx, c.config.MaskDType)
 	}
 
 	return maskTensor

llama/llama.cpp/src/llama-context.cpp

@@ -962,8 +962,7 @@ int llama_context::decode(const llama_batch & batch_inp) {
     const int64_t n_vocab = vocab.n_tokens();
     const int64_t n_embd  = hparams.n_embd;
 
-    // when computing embeddings, all tokens are output
-    const bool output_all = cparams.embeddings;
+    const bool output_all = false;
 
     if (!balloc->init(batch_inp, vocab, memory.get(), n_embd, cparams.kv_unified ? LLAMA_MAX_SEQ : cparams.n_seq_max, output_all)) {
         LLAMA_LOG_ERROR("%s: failed to initialize batch\n", __func__);

llama/patches/0019-Enable-CUDA-Graphs-for-gemma3n.patch

@@ -13,7 +13,7 @@ checks.
  1 file changed, 18 insertions(+)
 
 diff --git a/ggml/src/ggml-cuda/ggml-cuda.cu b/ggml/src/ggml-cuda/ggml-cuda.cu
-index 57eae461..9db0c8b5 100644
+index 57eae461..c7f9dc3a 100644
 --- a/ggml/src/ggml-cuda/ggml-cuda.cu
 +++ b/ggml/src/ggml-cuda/ggml-cuda.cu
 @@ -2671,12 +2671,24 @@ static bool check_node_graph_compatibility_and_refresh_copy_ops(ggml_backend_cud

llama/patches/0023-decode-disable-output_all.patch

@@ -0,0 +1,23 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Michael Yang <git@mxy.ng>
+Date: Mon, 18 Aug 2025 16:58:39 -0700
+Subject: [PATCH] decode: disable output_all
+
+---
+ src/llama-context.cpp | 3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+diff --git a/src/llama-context.cpp b/src/llama-context.cpp
+index 26a5cf9c..6ece5263 100644
+--- a/src/llama-context.cpp
++++ b/src/llama-context.cpp
+@@ -962,8 +962,7 @@ int llama_context::decode(const llama_batch & batch_inp) {
+     const int64_t n_vocab = vocab.n_tokens();
+     const int64_t n_embd  = hparams.n_embd;
+ 
+-    // when computing embeddings, all tokens are output
+-    const bool output_all = cparams.embeddings;
++    const bool output_all = false;
+ 
+     if (!balloc->init(batch_inp, vocab, memory.get(), n_embd, cparams.kv_unified ? LLAMA_MAX_SEQ : cparams.n_seq_max, output_all)) {
+         LLAMA_LOG_ERROR("%s: failed to initialize batch\n", __func__);

llm/server.go

@@ -651,7 +651,9 @@ func (s *ollamaServer) Load(ctx context.Context, gpus discover.GpuInfoList, requ
 		if !success {
 			s.initModel(ctx, LoadRequest{}, LoadOperationClose)
 		}
-		s.mem.Log(slog.LevelInfo)
+		if s.mem != nil {
+			s.mem.Log(slog.LevelInfo)
+		}
 	}()
 
 	slog.Info("loading model", "model layers", s.totalLayers, "requested", s.options.NumGPU)

ml/backend.go

@@ -396,6 +396,7 @@ type Tensor interface {
 
 	Shape() []int
 	DType() DType
+	Cast(ctx Context, dtype DType) Tensor
 
 	Bytes() []byte
 	Floats() []float32

ml/backend/ggml/ggml.go

@@ -843,23 +843,7 @@ func (c *Context) newTensor(dtype ml.DType, shape []int) ml.Tensor {
 		panic("set Input or Layer before creating tensors")
 	}
 
-	var cdtype uint32
-	switch dtype {
-	case ml.DTypeF32:
-		cdtype = C.GGML_TYPE_F32
-	case ml.DTypeF16:
-		cdtype = C.GGML_TYPE_F16
-	case ml.DTypeQ80:
-		cdtype = C.GGML_TYPE_Q8_0
-	case ml.DTypeQ40:
-		cdtype = C.GGML_TYPE_Q4_0
-	case ml.DTypeI32:
-		cdtype = C.GGML_TYPE_I32
-	case ml.DTypeMXFP4:
-		cdtype = C.GGML_TYPE_MXFP4
-	default:
-		panic("unsupported dtype")
-	}
+	cdtype := ggmlDType(dtype)
 
 	if len(shape) < 1 || shape[0] == 0 {
 		var shape C.int64_t = 0
@@ -1056,6 +1040,32 @@ func (t *Tensor) DType() ml.DType {
 	}
 }
 
+func ggmlDType(dtype ml.DType) uint32 {
+	switch dtype {
+	case ml.DTypeF32:
+		return C.GGML_TYPE_F32
+	case ml.DTypeF16:
+		return C.GGML_TYPE_F16
+	case ml.DTypeQ80:
+		return C.GGML_TYPE_Q8_0
+	case ml.DTypeQ40:
+		return C.GGML_TYPE_Q4_0
+	case ml.DTypeI32:
+		return C.GGML_TYPE_I32
+	case ml.DTypeMXFP4:
+		return C.GGML_TYPE_MXFP4
+	default:
+		panic("unsupported dtype")
+	}
+}
+
+func (t *Tensor) Cast(ctx ml.Context, dtype ml.DType) ml.Tensor {
+	return &Tensor{
+		b: t.b,
+		t: C.ggml_cast(ctx.(*Context).ctx, t.t, ggmlDType(dtype)),
+	}
+}
+
 func (t *Tensor) Neg(ctx ml.Context) ml.Tensor {
 	return &Tensor{
 		b: t.b,

model/bytepairencoding.go

@@ -109,7 +109,7 @@ func (bpe BytePairEncoding) Encode(s string, addSpecial bool) ([]int32, error) {
 					r = 0x0143
 				case r <= 0x0020:
 					r = r + 0x0100
-				case r >= 0x007e && r <= 0x00a0:
+				case r >= 0x007f && r <= 0x00a0:
 					r = r + 0x00a2
 				}
 

model/bytepairencoding_test.go

@@ -207,6 +207,36 @@ func TestLlama(t *testing.T) {
 			}
 		}
 	})
+
+	t.Run("roundtriping 0x00-0xFF", func(t *testing.T) {
+		t.Parallel()
+
+		for b := 0x00; b <= 0xFF; b++ {
+			input := string(rune(b))
+			ids, err := tokenizer.Encode(input, false)
+			if err != nil {
+				t.Errorf("failed to encode rune 0x%02X: %v", b, err)
+				continue
+			}
+
+			decoded, err := tokenizer.Decode(ids)
+			if err != nil {
+				t.Errorf("failed to decode rune 0x%02X: %v", b, err)
+				continue
+			}
+
+			if b == 0x00 {
+				if len(decoded) != 0 {
+					t.Errorf("Decode(Encode(0x00)) should be empty, got %v", ids)
+				}
+				continue
+			}
+
+			if decoded != input {
+				t.Errorf("rune 0x%02X failed roundtrip: got %q, want %q", b, decoded, input)
+			}
+		}
+	})
 }
 
 func BenchmarkBytePairEncoding(b *testing.B) {

server/harmonyparser.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"context"
+	"fmt"
 	"log/slog"
 	"slices"
 	"strings"
@@ -275,8 +276,9 @@ const (
 // HarmonyMessageHandler processes harmony events and accumulates content appropriately.
 // This is a higher level interface that maps harmony concepts into ollama concepts
 type HarmonyMessageHandler struct {
-	state         harmonyMessageState
-	harmonyParser *HarmonyParser
+	state           harmonyMessageState
+	harmonyParser   *HarmonyParser
+	functionNameMap *FunctionNameMap
 }
 
 // NewHarmonyMessageHandler creates a new message handler
@@ -288,6 +290,7 @@ func NewHarmonyMessageHandler() *HarmonyMessageHandler {
 			MessageEndTag:   "<|end|>",
 			HeaderEndTag:    "<|message|>",
 		},
+		functionNameMap: NewFunctionNameMap(),
 	}
 }
 
@@ -378,3 +381,97 @@ func (a *HarmonyToolCallAccumulator) Drain() (*string, string) {
 func (a *HarmonyToolCallAccumulator) Content() string {
 	return a.acc.String()
 }
+
+// FunctionNameMap maps a user-specified function name to a valid function
+// name for harmony (which look like TypeScript identifiers). This is needed to
+// transform user-specified function names, which might contain characters that
+// are not allowed in TypeScript identifiers
+type FunctionNameMap struct {
+	userToHarmony map[string]string
+	harmonyToUser map[string]string
+}
+
+func NewFunctionNameMap() *FunctionNameMap {
+	return &FunctionNameMap{
+		userToHarmony: make(map[string]string),
+		harmonyToUser: make(map[string]string),
+	}
+}
+
+func (m *FunctionNameMap) ConvertAndAdd(userFunctionName string) string {
+	harmonyFunctionName := m.deriveName(userFunctionName)
+	m.userToHarmony[userFunctionName] = harmonyFunctionName
+	m.harmonyToUser[harmonyFunctionName] = userFunctionName
+	return harmonyFunctionName
+}
+
+// OriginalFromConverted looks up the reverse-mapping of a previously-converted
+// user->harmony function name. To unmap reliably, the mapping must exist, as
+// the conversion process is not reversible without the appropriate state
+func (m *FunctionNameMap) OriginalFromConverted(harmonyFunctionName string) string {
+	if userFunctionName, ok := m.harmonyToUser[harmonyFunctionName]; ok {
+		return userFunctionName
+	}
+	slog.Warn("harmony parser: no reverse mapping found for function name", "harmonyFunctionName", harmonyFunctionName)
+	// fallback to the original function name if we can't find a mapping
+	return harmonyFunctionName
+}
+
+// convertToValidChars converts a user-specified function name to a valid
+// TypeScript identifier.
+//
+// Limitations:
+//
+//   - This doesn't restrict reserved TypeScript keywords.
+//   - We don't perform a real ID_Start/ID_Continue check, and instead use the more
+//     restrictive unicode.IsLetter/unicode.IsDigit check. Unclear what kind of
+//     identifiers these models were trained on, so in the end we might want to
+//     convert unicode-heavy identifiers to their closest ASCII equivalents.
+func (m *FunctionNameMap) convertToValidChars(userFunctionName string) string {
+	mapper := func(r rune) rune {
+		// first, replace certain characters with underscores
+		if r == ' ' || r == '-' || r == '.' {
+			return '_'
+		}
+
+		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '$' {
+			return r
+		}
+
+		// finally, remove any other characters
+		return -1
+	}
+	candidate := strings.Map(mapper, userFunctionName)
+
+	// set a default name if we end up with nothing left
+	if candidate == "" {
+		return "unnamed"
+	}
+
+	// if the candidate starts with a number, prepend an underscore to make it a
+	// valid identifier
+	if unicode.IsDigit(rune(candidate[0])) {
+		candidate = "_" + candidate
+	}
+
+	return candidate
+}
+
+func (m *FunctionNameMap) deriveName(userFunctionName string) string {
+	originalCandidate := m.convertToValidChars(userFunctionName)
+	candidate := originalCandidate
+
+	// Check for dupes, and if so, add a number to the end.
+	// We start at 2 because if we have dupes and the first is never renamed, it
+	// makes sense for them to be named, say, `f`, `f_2`, `f_3`
+	count := 2
+	for {
+		if _, exists := m.harmonyToUser[candidate]; !exists {
+			break
+		}
+		candidate = fmt.Sprintf("%s_%d", originalCandidate, count)
+		count++
+	}
+
+	return candidate
+}

server/harmonyparser_test.go

@@ -467,3 +467,71 @@ func TestHarmonyParserStreaming(t *testing.T) {
 		})
 	}
 }
+
+// TestFunctionConvertToValidChars tests only FunctionNameMap.convert(), which doesn't
+// handle any saving (and therefore no dupe handling)
+func TestFunctionConvertToValidChars(t *testing.T) {
+	tests := []struct {
+		name string
+		in   string
+		want string
+	}{
+		{name: "replace spaces with underscores", in: "get weather", want: "get_weather"},
+		{name: "replace hyphens with underscores", in: "get-weather", want: "get_weather"},
+		{name: "replace periods with underscores", in: "get.weather", want: "get_weather"},
+		{name: "disallow non-word characters", in: "get weather!", want: "get_weather"},
+		{name: "strip out invalid non-alphanumeric unicode characters", in: "a🫠bc", want: "abc"},
+		{name: "names that only contain invalid characters", in: "🫠", want: "unnamed"},
+		{name: "leading number", in: "123", want: "_123"},
+		{name: "$ allowed", in: "$", want: "$"},
+		// show that we allow weird unicode letter characters, though we might want
+		// to convert them to their closest ASCII equivalents in the future
+		{name: "allow weird unicode letter characters", in: "𝓸𝓵𝓵𝓪𝓶𝓪", want: "𝓸𝓵𝓵𝓪𝓶𝓪"},
+		// names that look like words but are invalid (i.e., not ID_Start/ID_Continue)
+		{name: "disallow non-word characters that look like words", in: "ⓞⓛⓛⓐⓜⓐ123", want: "_123"},
+	}
+
+	for i, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			parser := NewFunctionNameMap()
+			got := parser.convertToValidChars(tt.in)
+			if got != tt.want {
+				t.Errorf("case %d: got %q, want %q", i, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestFunctionConvertAndAdd(t *testing.T) {
+	// make a fresh map for each test, but within a test use the same map so we can test for dupe handling
+	tests := []struct {
+		name string
+		in   []string
+		want []string
+	}{
+		{name: "basic dupe handling", in: []string{"get weather", "get weather"}, want: []string{"get_weather", "get_weather_2"}},
+		{name: "dupes from different user-specified names", in: []string{"get weather", "get_weather", "get-weather"}, want: []string{"get_weather", "get_weather_2", "get_weather_3"}},
+		{name: "non dupes after dupes", in: []string{"get weather", "get_weather", "get-weather", "something-different"}, want: []string{"get_weather", "get_weather_2", "get_weather_3", "something_different"}},
+		{name: "multiple sets of dupes", in: []string{"a", "a", "b", "a", "a", "b", "a"}, want: []string{"a", "a_2", "b", "a_3", "a_4", "b_2", "a_5"}},
+	}
+
+	for i, tt := range tests {
+		parser := NewFunctionNameMap()
+		t.Run(tt.name, func(t *testing.T) {
+			for j, in := range tt.in {
+				got := parser.ConvertAndAdd(in)
+				want := tt.want[j]
+				if got != want {
+					t.Errorf("case %d: got %q, want %q", i, got, want)
+				}
+				// check that the maps are correct
+				if parser.userToHarmony[in] != want {
+					t.Errorf("case %d: userToHarmony[%q] = %q, want %q", i, in, parser.userToHarmony[in], want)
+				}
+				if parser.harmonyToUser[want] != in {
+					t.Errorf("case %d: harmonyToUser[%q] = %q, want %q", i, want, parser.harmonyToUser[want], in)
+				}
+			}
+		})
+	}
+}

server/routes.go

@@ -314,6 +314,19 @@ func (s *Server) GenerateHandler(c *gin.Context) {
 		prompt = b.String()
 	}
 
+	// If debug mode is enabled, return the rendered template instead of calling the model
+	if req.DebugRenderOnly {
+		c.JSON(http.StatusOK, api.DebugTemplateResponse{
+			Model:     req.Model,
+			CreatedAt: time.Now().UTC(),
+			DebugInfo: api.DebugInfo{
+				RenderedTemplate: prompt,
+				ImageCount:       len(images),
+			},
+		})
+		return
+	}
+
 	var thinkingState *thinking.Parser
 	if !useHarmony {
 		openingTag, closingTag := thinking.InferTags(m.Template.Template)
@@ -1590,24 +1603,12 @@ func (s *Server) ChatHandler(c *gin.Context) {
 	}
 	msgs = filterThinkTags(msgs, m)
 
-	prompt, images, err := chatPrompt(c.Request.Context(), m, r.Tokenize, opts, msgs, req.Tools, req.Think)
-	if err != nil {
-		slog.Error("chat prompt error", "error", err)
-		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
-		return
-	}
-
-	useHarmony := shouldUseHarmony(*m)
-
-	// Validate Think value: string values currently only allowed for gptoss models
-	if req.Think != nil && req.Think.IsString() && !useHarmony {
-		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("think value %q is not supported for this model", req.Think.String())})
-		return
-	}
-
 	var harmonyMessageHandler *HarmonyMessageHandler
 	var harmonyToolParser *HarmonyToolCallAccumulator
 
+	useHarmony := shouldUseHarmony(*m)
+
+	processedTools := req.Tools
 	if useHarmony {
 		harmonyMessageHandler = NewHarmonyMessageHandler()
 		var lastMessage *api.Message
@@ -1616,6 +1617,40 @@ func (s *Server) ChatHandler(c *gin.Context) {
 		}
 		harmonyMessageHandler.harmonyParser.AddImplicitStartOrPrefill(lastMessage)
 		harmonyToolParser = harmonyMessageHandler.CreateToolParser()
+
+		// make a copy of tools to pass to the chat prompt. Function names may be
+		// renamed to be valid Harmony function names.
+		processedTools = make([]api.Tool, len(req.Tools))
+		copy(processedTools, req.Tools)
+		for i, tool := range processedTools {
+			processedTools[i].Function.Name = harmonyMessageHandler.functionNameMap.ConvertAndAdd(tool.Function.Name)
+		}
+	}
+
+	prompt, images, err := chatPrompt(c.Request.Context(), m, r.Tokenize, opts, msgs, processedTools, req.Think)
+	if err != nil {
+		slog.Error("chat prompt error", "error", err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	// If debug mode is enabled, return the rendered template instead of calling the model
+	if req.DebugRenderOnly {
+		c.JSON(http.StatusOK, api.DebugTemplateResponse{
+			Model:     req.Model,
+			CreatedAt: time.Now().UTC(),
+			DebugInfo: api.DebugInfo{
+				RenderedTemplate: prompt,
+				ImageCount:       len(images),
+			},
+		})
+		return
+	}
+
+	// Validate Think value: string values currently only allowed for gptoss models
+	if req.Think != nil && req.Think.IsString() && !useHarmony {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("think value %q is not supported for this model", req.Think.String())})
+		return
 	}
 
 	var thinkingState *thinking.Parser
@@ -1670,6 +1705,7 @@ func (s *Server) ChatHandler(c *gin.Context) {
 					toolName, toolContent := harmonyToolParser.Drain()
 					if toolName != nil {
 						*toolName = strings.TrimPrefix(*toolName, "functions.")
+						*toolName = harmonyMessageHandler.functionNameMap.OriginalFromConverted(*toolName)
 						var args api.ToolCallFunctionArguments
 						if err := json.Unmarshal([]byte(toolContent), &args); err != nil {
 							errStr := fmt.Sprintf("error parsing tool call: raw='%s', err=%s", toolContent, err.Error())

server/routes_debug_test.go

@@ -0,0 +1,413 @@
+package server
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/ollama/ollama/api"
+	"github.com/ollama/ollama/discover"
+	"github.com/ollama/ollama/fs/ggml"
+	"github.com/ollama/ollama/llm"
+)
+
+func TestGenerateDebugRenderOnly(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	mock := mockRunner{
+		CompletionResponse: llm.CompletionResponse{
+			Done:               true,
+			DoneReason:         llm.DoneReasonStop,
+			PromptEvalCount:    1,
+			PromptEvalDuration: 1,
+			EvalCount:          1,
+			EvalDuration:       1,
+		},
+	}
+
+	s := Server{
+		sched: &Scheduler{
+			pendingReqCh:  make(chan *LlmRequest, 1),
+			finishedReqCh: make(chan *LlmRequest, 1),
+			expiredCh:     make(chan *runnerRef, 1),
+			unloadedCh:    make(chan any, 1),
+			loaded:        make(map[string]*runnerRef),
+			newServerFn:   newMockServer(&mock),
+			getGpuFn:      discover.GetGPUInfo,
+			getCpuFn:      discover.GetCPUInfo,
+			reschedDelay:  250 * time.Millisecond,
+			loadFn: func(req *LlmRequest, _ *ggml.GGML, _ discover.GpuInfoList, _ bool) bool {
+				// add small delay to simulate loading
+				time.Sleep(time.Millisecond)
+				req.successCh <- &runnerRef{
+					llama: &mock,
+				}
+				return false
+			},
+		},
+	}
+
+	go s.sched.Run(t.Context())
+
+	// Create a test model
+	stream := false
+	_, digest := createBinFile(t, ggml.KV{
+		"general.architecture":          "llama",
+		"llama.block_count":             uint32(1),
+		"llama.context_length":          uint32(8192),
+		"llama.embedding_length":        uint32(4096),
+		"llama.attention.head_count":    uint32(32),
+		"llama.attention.head_count_kv": uint32(8),
+		"tokenizer.ggml.tokens":         []string{""},
+		"tokenizer.ggml.scores":         []float32{0},
+		"tokenizer.ggml.token_type":     []int32{0},
+	}, []*ggml.Tensor{
+		{Name: "token_embd.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_norm.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_down.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_gate.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_up.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_norm.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_k.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_output.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_q.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_v.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "output.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+	})
+
+	w := createRequest(t, s.CreateHandler, api.CreateRequest{
+		Model:    "test-model",
+		Files:    map[string]string{"file.gguf": digest},
+		Template: "{{ .Prompt }}",
+		Stream:   &stream,
+	})
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected status 200, got %d", w.Code)
+	}
+
+	tests := []struct {
+		name            string
+		request         api.GenerateRequest
+		expectDebug     bool
+		expectTemplate  string
+		expectNumImages int
+	}{
+		{
+			name: "debug render only enabled",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "Hello, world!",
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "Hello, world!",
+		},
+		{
+			name: "debug render only disabled",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "Hello, world!",
+				DebugRenderOnly: false,
+			},
+			expectDebug: false,
+		},
+		{
+			name: "debug render only with system prompt",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "User question",
+				System:          "You are a helpful assistant",
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "User question",
+		},
+		{
+			name: "debug render only with template",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "Hello",
+				Template:        "PROMPT: {{ .Prompt }}",
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "PROMPT: Hello",
+		},
+		{
+			name: "debug render only with images",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "Describe this image",
+				Images:          []api.ImageData{[]byte("fake-image-data")},
+				DebugRenderOnly: true,
+			},
+			expectDebug:     true,
+			expectTemplate:  "[img-0]\n\nDescribe this image",
+			expectNumImages: 1,
+		},
+		{
+			name: "debug render only with raw mode",
+			request: api.GenerateRequest{
+				Model:           "test-model",
+				Prompt:          "Raw prompt text",
+				Raw:             true,
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "Raw prompt text",
+		},
+	}
+
+	for _, tt := range tests {
+		// Test both with and without streaming
+		streamValues := []bool{false, true}
+		for _, stream := range streamValues {
+			streamSuffix := ""
+			if stream {
+				streamSuffix = " (streaming)"
+			}
+			t.Run(tt.name+streamSuffix, func(t *testing.T) {
+				req := tt.request
+				req.Stream = &stream
+				w := createRequest(t, s.GenerateHandler, req)
+
+				if tt.expectDebug {
+					if w.Code != http.StatusOK {
+						t.Errorf("expected status %d, got %d, body: %s", http.StatusOK, w.Code, w.Body.String())
+					}
+
+					var response api.DebugTemplateResponse
+					if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+						t.Fatalf("failed to unmarshal response: %v", err)
+					}
+
+					if response.Model != tt.request.Model {
+						t.Errorf("expected model %s, got %s", tt.request.Model, response.Model)
+					}
+
+					if tt.expectTemplate != "" && response.DebugInfo.RenderedTemplate != tt.expectTemplate {
+						t.Errorf("expected template %q, got %q", tt.expectTemplate, response.DebugInfo.RenderedTemplate)
+					}
+
+					if tt.expectNumImages > 0 && response.DebugInfo.ImageCount != tt.expectNumImages {
+						t.Errorf("expected image count %d, got %d", tt.expectNumImages, response.DebugInfo.ImageCount)
+					}
+				} else {
+					// When debug is disabled, it should attempt normal processing
+					if w.Code != http.StatusOK {
+						t.Errorf("expected status %d, got %d", http.StatusOK, w.Code)
+					}
+				}
+			})
+		}
+	}
+}
+
+func TestChatDebugRenderOnly(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	mock := mockRunner{
+		CompletionResponse: llm.CompletionResponse{
+			Done:               true,
+			DoneReason:         llm.DoneReasonStop,
+			PromptEvalCount:    1,
+			PromptEvalDuration: 1,
+			EvalCount:          1,
+			EvalDuration:       1,
+		},
+	}
+
+	s := Server{
+		sched: &Scheduler{
+			pendingReqCh:  make(chan *LlmRequest, 1),
+			finishedReqCh: make(chan *LlmRequest, 1),
+			expiredCh:     make(chan *runnerRef, 1),
+			unloadedCh:    make(chan any, 1),
+			loaded:        make(map[string]*runnerRef),
+			newServerFn:   newMockServer(&mock),
+			getGpuFn:      discover.GetGPUInfo,
+			getCpuFn:      discover.GetCPUInfo,
+			reschedDelay:  250 * time.Millisecond,
+			loadFn: func(req *LlmRequest, _ *ggml.GGML, _ discover.GpuInfoList, _ bool) bool {
+				// add small delay to simulate loading
+				time.Sleep(time.Millisecond)
+				req.successCh <- &runnerRef{
+					llama: &mock,
+				}
+				return false
+			},
+		},
+	}
+
+	go s.sched.Run(t.Context())
+
+	// Create a test model
+	stream := false
+	_, digest := createBinFile(t, ggml.KV{
+		"general.architecture":          "llama",
+		"llama.block_count":             uint32(1),
+		"llama.context_length":          uint32(8192),
+		"llama.embedding_length":        uint32(4096),
+		"llama.attention.head_count":    uint32(32),
+		"llama.attention.head_count_kv": uint32(8),
+		"tokenizer.ggml.tokens":         []string{""},
+		"tokenizer.ggml.scores":         []float32{0},
+		"tokenizer.ggml.token_type":     []int32{0},
+	}, []*ggml.Tensor{
+		{Name: "token_embd.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_norm.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_down.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_gate.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_up.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.ffn_norm.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_k.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_output.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_q.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "blk.0.attn_v.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+		{Name: "output.weight", Shape: []uint64{1}, WriterTo: bytes.NewReader(make([]byte, 4))},
+	})
+
+	w := createRequest(t, s.CreateHandler, api.CreateRequest{
+		Model:    "test-model",
+		Files:    map[string]string{"file.gguf": digest},
+		Template: "{{ if .Tools }}{{ .Tools }}{{ end }}{{ range .Messages }}{{ .Role }}: {{ .Content }}\n{{ end }}",
+		Stream:   &stream,
+	})
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected status 200, got %d", w.Code)
+	}
+
+	tests := []struct {
+		name            string
+		request         api.ChatRequest
+		expectDebug     bool
+		expectTemplate  string
+		expectNumImages int
+	}{
+		{
+			name: "chat debug render only enabled",
+			request: api.ChatRequest{
+				Model: "test-model",
+				Messages: []api.Message{
+					{Role: "system", Content: "You are a helpful assistant"},
+					{Role: "user", Content: "Hello"},
+				},
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "system: You are a helpful assistant\nuser: Hello\n",
+		},
+		{
+			name: "chat debug render only disabled",
+			request: api.ChatRequest{
+				Model: "test-model",
+				Messages: []api.Message{
+					{Role: "user", Content: "Hello"},
+				},
+				DebugRenderOnly: false,
+			},
+			expectDebug: false,
+		},
+		{
+			name: "chat debug with assistant message",
+			request: api.ChatRequest{
+				Model: "test-model",
+				Messages: []api.Message{
+					{Role: "user", Content: "Hello"},
+					{Role: "assistant", Content: "Hi there!"},
+					{Role: "user", Content: "How are you?"},
+				},
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "user: Hello\nassistant: Hi there!\nuser: How are you?\n",
+		},
+		{
+			name: "chat debug with images",
+			request: api.ChatRequest{
+				Model: "test-model",
+				Messages: []api.Message{
+					{
+						Role:    "user",
+						Content: "What's in this image?",
+						Images:  []api.ImageData{[]byte("fake-image-data")},
+					},
+				},
+				DebugRenderOnly: true,
+			},
+			expectDebug:     true,
+			expectTemplate:  "user: [img-0]What's in this image?\n",
+			expectNumImages: 1,
+		},
+		{
+			name: "chat debug with tools",
+			request: api.ChatRequest{
+				Model: "test-model",
+				Messages: []api.Message{
+					{Role: "user", Content: "Get the weather"},
+				},
+				Tools: api.Tools{
+					{
+						Type: "function",
+						Function: api.ToolFunction{
+							Name:        "get_weather",
+							Description: "Get weather information",
+						},
+					},
+				},
+				DebugRenderOnly: true,
+			},
+			expectDebug:    true,
+			expectTemplate: "[{\"type\":\"function\",\"function\":{\"name\":\"get_weather\",\"description\":\"Get weather information\",\"parameters\":{\"type\":\"\",\"required\":null,\"properties\":null}}}]user: Get the weather\n",
+		},
+	}
+
+	for _, tt := range tests {
+		// Test both with and without streaming
+		streamValues := []bool{false, true}
+		for _, stream := range streamValues {
+			streamSuffix := ""
+			if stream {
+				streamSuffix = " (streaming)"
+			}
+			t.Run(tt.name+streamSuffix, func(t *testing.T) {
+				req := tt.request
+				req.Stream = &stream
+				w := createRequest(t, s.ChatHandler, req)
+
+				if tt.expectDebug {
+					if w.Code != http.StatusOK {
+						t.Errorf("expected status %d, got %d, body: %s", http.StatusOK, w.Code, w.Body.String())
+					}
+
+					var response api.DebugTemplateResponse
+					if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
+						t.Fatalf("failed to unmarshal response: %v", err)
+					}
+
+					if response.Model != tt.request.Model {
+						t.Errorf("expected model %s, got %s", tt.request.Model, response.Model)
+					}
+
+					if tt.expectTemplate != "" && response.DebugInfo.RenderedTemplate != tt.expectTemplate {
+						t.Errorf("expected template %q, got %q", tt.expectTemplate, response.DebugInfo.RenderedTemplate)
+					}
+
+					if tt.expectNumImages > 0 && response.DebugInfo.ImageCount != tt.expectNumImages {
+						t.Errorf("expected image count %d, got %d", tt.expectNumImages, response.DebugInfo.ImageCount)
+					}
+				} else {
+					// When debug is disabled, it should attempt normal processing
+					if w.Code != http.StatusOK {
+						t.Errorf("expected status %d, got %d", http.StatusOK, w.Code)
+					}
+				}
+			})
+		}
+	}
+}