chat api endpoint (#1392)

README.md

@@ -214,6 +214,17 @@ curl http://localhost:11434/api/generate -d '{
 }'
 ```
 
+Or send a chat message:
+
+```
+curl http://localhost:11434/api/chat -d '{
+  "model": "mistral",
+  "messages": [ 
+    { "role": "user", "content": "why is the sky blue?" } 
+  ]
+}'
+```
+
 See the [API documentation](./docs/api.md) for all endpoints.
 
 ## Community Integrations

api/client.go

@@ -221,6 +221,19 @@ func (c *Client) Generate(ctx context.Context, req *GenerateRequest, fn Generate
 	})
 }
 
+type ChatResponseFunc func(ChatResponse) error
+
+func (c *Client) Chat(ctx context.Context, req *ChatRequest, fn ChatResponseFunc) error {
+	return c.stream(ctx, http.MethodPost, "/api/chat", req, func(bts []byte) error {
+		var resp ChatResponse
+		if err := json.Unmarshal(bts, &resp); err != nil {
+			return err
+		}
+
+		return fn(resp)
+	})
+}
+
 type PullProgressFunc func(ProgressResponse) error
 
 func (c *Client) Pull(ctx context.Context, req *PullRequest, fn PullProgressFunc) error {

api/types.go

@@ -44,6 +44,39 @@ type GenerateRequest struct {
 	Options map[string]interface{} `json:"options"`
 }
 
+type ChatRequest struct {
+	Model    string    `json:"model"`
+	Messages []Message `json:"messages"`
+	Stream   *bool     `json:"stream,omitempty"`
+	Format   string    `json:"format"`
+
+	Options map[string]interface{} `json:"options"`
+}
+
+type Message struct {
+	Role    string `json:"role"` // one of ["system", "user", "assistant"]
+	Content string `json:"content"`
+}
+
+type ChatResponse struct {
+	Model     string    `json:"model"`
+	CreatedAt time.Time `json:"created_at"`
+	Message   *Message  `json:"message,omitempty"`
+
+	Done bool `json:"done"`
+
+	Metrics
+}
+
+type Metrics struct {
+	TotalDuration      time.Duration `json:"total_duration,omitempty"`
+	LoadDuration       time.Duration `json:"load_duration,omitempty"`
+	PromptEvalCount    int           `json:"prompt_eval_count,omitempty"`
+	PromptEvalDuration time.Duration `json:"prompt_eval_duration,omitempty"`
+	EvalCount          int           `json:"eval_count,omitempty"`
+	EvalDuration       time.Duration `json:"eval_duration,omitempty"`
+}
+
 // Options specfied in GenerateRequest, if you add a new option here add it to the API docs also
 type Options struct {
 	Runner
@@ -173,39 +206,34 @@ type GenerateResponse struct {
 	Done    bool  `json:"done"`
 	Context []int `json:"context,omitempty"`
 
-	TotalDuration      time.Duration `json:"total_duration,omitempty"`
-	LoadDuration       time.Duration `json:"load_duration,omitempty"`
-	PromptEvalCount    int           `json:"prompt_eval_count,omitempty"`
-	PromptEvalDuration time.Duration `json:"prompt_eval_duration,omitempty"`
-	EvalCount          int           `json:"eval_count,omitempty"`
-	EvalDuration       time.Duration `json:"eval_duration,omitempty"`
+	Metrics
 }
 
-func (r *GenerateResponse) Summary() {
-	if r.TotalDuration > 0 {
-		fmt.Fprintf(os.Stderr, "total duration:       %v\n", r.TotalDuration)
+func (m *Metrics) Summary() {
+	if m.TotalDuration > 0 {
+		fmt.Fprintf(os.Stderr, "total duration:       %v\n", m.TotalDuration)
 	}
 
-	if r.LoadDuration > 0 {
-		fmt.Fprintf(os.Stderr, "load duration:        %v\n", r.LoadDuration)
+	if m.LoadDuration > 0 {
+		fmt.Fprintf(os.Stderr, "load duration:        %v\n", m.LoadDuration)
 	}
 
-	if r.PromptEvalCount > 0 {
-		fmt.Fprintf(os.Stderr, "prompt eval count:    %d token(s)\n", r.PromptEvalCount)
+	if m.PromptEvalCount > 0 {
+		fmt.Fprintf(os.Stderr, "prompt eval count:    %d token(s)\n", m.PromptEvalCount)
 	}
 
-	if r.PromptEvalDuration > 0 {
-		fmt.Fprintf(os.Stderr, "prompt eval duration: %s\n", r.PromptEvalDuration)
-		fmt.Fprintf(os.Stderr, "prompt eval rate:     %.2f tokens/s\n", float64(r.PromptEvalCount)/r.PromptEvalDuration.Seconds())
+	if m.PromptEvalDuration > 0 {
+		fmt.Fprintf(os.Stderr, "prompt eval duration: %s\n", m.PromptEvalDuration)
+		fmt.Fprintf(os.Stderr, "prompt eval rate:     %.2f tokens/s\n", float64(m.PromptEvalCount)/m.PromptEvalDuration.Seconds())
 	}
 
-	if r.EvalCount > 0 {
-		fmt.Fprintf(os.Stderr, "eval count:           %d token(s)\n", r.EvalCount)
+	if m.EvalCount > 0 {
+		fmt.Fprintf(os.Stderr, "eval count:           %d token(s)\n", m.EvalCount)
 	}
 
-	if r.EvalDuration > 0 {
-		fmt.Fprintf(os.Stderr, "eval duration:        %s\n", r.EvalDuration)
-		fmt.Fprintf(os.Stderr, "eval rate:            %.2f tokens/s\n", float64(r.EvalCount)/r.EvalDuration.Seconds())
+	if m.EvalDuration > 0 {
+		fmt.Fprintf(os.Stderr, "eval duration:        %s\n", m.EvalDuration)
+		fmt.Fprintf(os.Stderr, "eval rate:            %.2f tokens/s\n", float64(m.EvalCount)/m.EvalDuration.Seconds())
 	}
 }
 

docs/api.md

@@ -24,7 +24,7 @@ All durations are returned in nanoseconds.
 
 ### Streaming responses
 
-Certain endpoints stream responses as JSON objects delineated with the newline (`\n`) character.
+Certain endpoints stream responses as JSON objects.
 
 ## Generate a completion
 
@@ -32,7 +32,7 @@ Certain endpoints stream responses as JSON objects delineated with the newline (
 POST /api/generate
 ```
 
-Generate a response for a given prompt with a provided model. This is a streaming endpoint, so will be a series of responses. The final response object will include statistics and additional data from the request.
+Generate a response for a given prompt with a provided model. This is a streaming endpoint, so there will be a series of responses. The final response object will include statistics and additional data from the request.
 
 ### Parameters
 
@@ -47,7 +47,7 @@ Advanced parameters (optional):
 - `template`: the full prompt or prompt template (overrides what is defined in the `Modelfile`)
 - `context`: the context parameter returned from a previous request to `/generate`, this can be used to keep a short conversational memory
 - `stream`: if `false` the response will be returned as a single response object, rather than a stream of objects
-- `raw`: if `true` no formatting will be applied to the prompt and no context will be returned. You may choose to use the `raw` parameter if you are specifying a full templated prompt in your request to the API, and are managing history yourself.
+- `raw`: if `true` no formatting will be applied to the prompt. You may choose to use the `raw` parameter if you are specifying a full templated prompt in your request to the API.
 
 ### JSON mode
 
@@ -57,7 +57,7 @@ Enable JSON mode by setting the `format` parameter to `json`. This will structur
 
 ### Examples
 
-#### Request
+#### Request (Prompt)
 
 ```shell
 curl http://localhost:11434/api/generate -d '{
@@ -114,6 +114,8 @@ To calculate how fast the response is generated in tokens per second (token/s),
 
 #### Request (No streaming)
 
+A response can be recieved in one reply when streaming is off.
+
 ```shell
 curl http://localhost:11434/api/generate -d '{
   "model": "llama2",
@@ -144,9 +146,9 @@ If `stream` is set to `false`, the response will be a single JSON object:
 }
 ```
 
-#### Request (Raw mode)
+#### Request (Raw Mode)
 
-In some cases you may wish to bypass the templating system and provide a full prompt. In this case, you can use the `raw` parameter to disable formatting and context.
+In some cases you may wish to bypass the templating system and provide a full prompt. In this case, you can use the `raw` parameter to disable formatting.
 
 ```shell
 curl http://localhost:11434/api/generate -d '{
@@ -164,6 +166,7 @@ curl http://localhost:11434/api/generate -d '{
   "model": "mistral",
   "created_at": "2023-11-03T15:36:02.583064Z",
   "response": " The sky appears blue because of a phenomenon called Rayleigh scattering.",
+  "context": [1, 2, 3],
   "done": true,
   "total_duration": 14648695333,
   "load_duration": 3302671417,
@@ -275,7 +278,6 @@ curl http://localhost:11434/api/generate -d '{
   "model": "llama2",
   "created_at": "2023-08-04T19:22:45.499127Z",
   "response": "The sky is blue because it is the color of the sky.",
-  "context": [1, 2, 3],
   "done": true,
   "total_duration": 5589157167,
   "load_duration": 3013701500,
@@ -288,6 +290,133 @@ curl http://localhost:11434/api/generate -d '{
 }
 ```
 
+## Send Chat Messages
+```shell
+POST /api/chat
+```
+
+Generate the next message in a chat with a provided model. This is a streaming endpoint, so there will be a series of responses. The final response object will include statistics and additional data from the request.
+
+### Parameters
+
+- `model`: (required) the [model name](#model-names)
+- `messages`: the messages of the chat, this can be used to keep a chat memory
+
+Advanced parameters (optional):
+
+- `format`: the format to return a response in. Currently the only accepted value is `json`
+- `options`: additional model parameters listed in the documentation for the [Modelfile](./modelfile.md#valid-parameters-and-values) such as `temperature`
+- `template`: the full prompt or prompt template (overrides what is defined in the `Modelfile`)
+- `stream`: if `false` the response will be returned as a single response object, rather than a stream of objects
+
+### Examples
+
+#### Request
+Send a chat message with a streaming response.
+
+```shell
+curl http://localhost:11434/api/generate -d '{
+  "model": "llama2",
+  "messages": [
+    {
+      "role": "user",
+      "content": "why is the sky blue?"
+    }
+  ]
+}'
+```
+
+#### Response
+
+A stream of JSON objects is returned:
+
+```json
+{
+  "model": "llama2",
+  "created_at": "2023-08-04T08:52:19.385406455-07:00",
+  "message": {
+    "role": "assisant",
+    "content": "The"
+  },
+  "done": false
+}
+```
+
+Final response:
+
+```json
+{
+  "model": "llama2",
+  "created_at": "2023-08-04T19:22:45.499127Z",
+  "done": true,
+  "total_duration": 5589157167,
+  "load_duration": 3013701500,
+  "sample_count": 114,
+  "sample_duration": 81442000,
+  "prompt_eval_count": 46,
+  "prompt_eval_duration": 1160282000,
+  "eval_count": 113,
+  "eval_duration": 1325948000
+}
+```
+
+#### Request (With History)
+Send a chat message with a conversation history.
+
+```shell
+curl http://localhost:11434/api/generate -d '{
+  "model": "llama2",
+  "messages": [
+    {
+      "role": "user",
+      "content": "why is the sky blue?"
+    },
+    {
+      "role": "assistant",
+      "content": "due to rayleigh scattering."
+    },
+    {
+      "role": "user",
+      "content": "how is that different than mie scattering?"
+    }
+  ]
+}'
+```
+
+#### Response
+
+A stream of JSON objects is returned:
+
+```json
+{
+  "model": "llama2",
+  "created_at": "2023-08-04T08:52:19.385406455-07:00",
+  "message": {
+    "role": "assisant",
+    "content": "The"
+  },
+  "done": false
+}
+```
+
+Final response:
+
+```json
+{
+  "model": "llama2",
+  "created_at": "2023-08-04T19:22:45.499127Z",
+  "done": true,
+  "total_duration": 5589157167,
+  "load_duration": 3013701500,
+  "sample_count": 114,
+  "sample_duration": 81442000,
+  "prompt_eval_count": 46,
+  "prompt_eval_duration": 1160282000,
+  "eval_count": 113,
+  "eval_duration": 1325948000
+}
+```
+
 ## Create a Model
 
 ```shell

llm/llama.go

@@ -531,21 +531,30 @@ type prediction struct {
 
 const maxBufferSize = 512 * format.KiloByte
 
-func (llm *llama) Predict(ctx context.Context, prevContext []int, prompt string, format string, fn func(api.GenerateResponse)) error {
-	prevConvo, err := llm.Decode(ctx, prevContext)
-	if err != nil {
-		return err
-	}
-
-	// Remove leading spaces from prevConvo if present
-	prevConvo = strings.TrimPrefix(prevConvo, " ")
-
-	var nextContext strings.Builder
-	nextContext.WriteString(prevConvo)
-	nextContext.WriteString(prompt)
-
+type PredictOpts struct {
+	Model            string
+	Prompt           string
+	Format           string
+	CheckpointStart  time.Time
+	CheckpointLoaded time.Time
+}
+
+type PredictResult struct {
+	Model              string
+	CreatedAt          time.Time
+	TotalDuration      time.Duration
+	LoadDuration       time.Duration
+	Content            string
+	Done               bool
+	PromptEvalCount    int
+	PromptEvalDuration time.Duration
+	EvalCount          int
+	EvalDuration       time.Duration
+}
+
+func (llm *llama) Predict(ctx context.Context, predict PredictOpts, fn func(PredictResult)) error {
 	request := map[string]any{
-		"prompt":            nextContext.String(),
+		"prompt":            predict.Prompt,
 		"stream":            true,
 		"n_predict":         llm.NumPredict,
 		"n_keep":            llm.NumKeep,
@@ -567,7 +576,7 @@ func (llm *llama) Predict(ctx context.Context, prevContext []int, prompt string,
 		"stop":              llm.Stop,
 	}
 
-	if format == "json" {
+	if predict.Format == "json" {
 		request["grammar"] = jsonGrammar
 	}
 
@@ -624,25 +633,25 @@ func (llm *llama) Predict(ctx context.Context, prevContext []int, prompt string,
 				}
 
 				if p.Content != "" {
-					fn(api.GenerateResponse{Response: p.Content})
-					nextContext.WriteString(p.Content)
+					fn(PredictResult{
+						Model:     predict.Model,
+						CreatedAt: time.Now().UTC(),
+						Content:   p.Content,
+					})
 				}
 
 				if p.Stop {
-					embd, err := llm.Encode(ctx, nextContext.String())
-					if err != nil {
-						return fmt.Errorf("encoding context: %v", err)
-					}
+					fn(PredictResult{
+						Model:         predict.Model,
+						CreatedAt:     time.Now().UTC(),
+						TotalDuration: time.Since(predict.CheckpointStart),
 
-					fn(api.GenerateResponse{
 						Done:               true,
-						Context:            embd,
 						PromptEvalCount:    p.Timings.PromptN,
 						PromptEvalDuration: parseDurationMs(p.Timings.PromptMS),
 						EvalCount:          p.Timings.PredictedN,
 						EvalDuration:       parseDurationMs(p.Timings.PredictedMS),
 					})
-
 					return nil
 				}
 			}

llm/llm.go

@@ -14,7 +14,7 @@ import (
 )
 
 type LLM interface {
-	Predict(context.Context, []int, string, string, func(api.GenerateResponse)) error
+	Predict(context.Context, PredictOpts, func(PredictResult)) error
 	Embedding(context.Context, string) ([]float64, error)
 	Encode(context.Context, string) ([]int, error)
 	Decode(context.Context, []int) (string, error)

server/images.go

@@ -47,37 +47,85 @@ type Model struct {
 	Options       map[string]interface{}
 }
 
-func (m *Model) Prompt(request api.GenerateRequest) (string, error) {
-	t := m.Template
-	if request.Template != "" {
-		t = request.Template
-	}
+type PromptVars struct {
+	System   string
+	Prompt   string
+	Response string
+	First    bool
+}
 
-	tmpl, err := template.New("").Parse(t)
+func (m *Model) Prompt(p PromptVars) (string, error) {
+	var prompt strings.Builder
+	tmpl, err := template.New("").Parse(m.Template)
 	if err != nil {
 		return "", err
 	}
 
-	var vars struct {
-		First  bool
-		System string
-		Prompt string
+	if p.System == "" {
+		// use the default system prompt for this model if one is not specified
+		p.System = m.System
 	}
 
-	vars.First = len(request.Context) == 0
-	vars.System = m.System
-	vars.Prompt = request.Prompt
+	var sb strings.Builder
+	if err := tmpl.Execute(&sb, p); err != nil {
+		return "", err
+	}
+	prompt.WriteString(sb.String())
+	prompt.WriteString(p.Response)
+	return prompt.String(), nil
+}
 
-	if request.System != "" {
-		vars.System = request.System
+func (m *Model) ChatPrompt(msgs []api.Message) (string, error) {
+	// build the prompt from the list of messages
+	var prompt strings.Builder
+	currentVars := PromptVars{
+		First: true,
 	}
 
-	var sb strings.Builder
-	if err := tmpl.Execute(&sb, vars); err != nil {
-		return "", err
+	writePrompt := func() error {
+		p, err := m.Prompt(currentVars)
+		if err != nil {
+			return err
+		}
+		prompt.WriteString(p)
+		currentVars = PromptVars{}
+		return nil
 	}
 
-	return sb.String(), nil
+	for _, msg := range msgs {
+		switch msg.Role {
+		case "system":
+			if currentVars.Prompt != "" || currentVars.System != "" {
+				if err := writePrompt(); err != nil {
+					return "", err
+				}
+			}
+			currentVars.System = msg.Content
+		case "user":
+			if currentVars.Prompt != "" || currentVars.System != "" {
+				if err := writePrompt(); err != nil {
+					return "", err
+				}
+			}
+			currentVars.Prompt = msg.Content
+		case "assistant":
+			currentVars.Response = msg.Content
+			if err := writePrompt(); err != nil {
+				return "", err
+			}
+		default:
+			return "", fmt.Errorf("invalid role: %s, role must be one of [system, user, assistant]", msg.Role)
+		}
+	}
+
+	// Append the last set of vars if they are non-empty
+	if currentVars.Prompt != "" || currentVars.System != "" {
+		if err := writePrompt(); err != nil {
+			return "", err
+		}
+	}
+
+	return prompt.String(), nil
 }
 
 type ManifestV2 struct {
@@ -383,7 +431,7 @@ func CreateModel(ctx context.Context, name, modelFileDir string, commands []pars
 
 				c.Args = blobPath
 			}
-			
+
 			fn(api.ProgressResponse{Status: "creating adapter layer"})
 			bin, err := os.Open(realpath(modelFileDir, c.Args))
 			if err != nil {

server/images_test.go

@@ -2,17 +2,15 @@ package server
 
 import (
 	"testing"
-
-	"github.com/jmorganca/ollama/api"
 )
 
 func TestModelPrompt(t *testing.T) {
-	var m Model
-	req := api.GenerateRequest{
+	m := Model{
 		Template: "a{{ .Prompt }}b",
-		Prompt:   "<h1>",
 	}
-	s, err := m.Prompt(req)
+	s, err := m.Prompt(PromptVars{
+		Prompt: "<h1>",
+	})
 	if err != nil {
 		t.Fatal(err)
 	}

server/routes.go

@@ -60,17 +60,26 @@ var loaded struct {
 var defaultSessionDuration = 5 * time.Minute
 
 // load a model into memory if it is not already loaded, it is up to the caller to lock loaded.mu before calling this function
-func load(ctx context.Context, workDir string, model *Model, reqOpts map[string]interface{}, sessionDuration time.Duration) error {
+func load(c *gin.Context, modelName string, reqOpts map[string]interface{}, sessionDuration time.Duration) (*Model, error) {
+	model, err := GetModel(modelName)
+	if err != nil {
+		return nil, err
+	}
+
+	workDir := c.GetString("workDir")
+
 	opts := api.DefaultOptions()
 	if err := opts.FromMap(model.Options); err != nil {
 		log.Printf("could not load model options: %v", err)
-		return err
+		return nil, err
 	}
 
 	if err := opts.FromMap(reqOpts); err != nil {
-		return err
+		return nil, err
 	}
 
+	ctx := c.Request.Context()
+
 	// check if the loaded model is still running in a subprocess, in case something unexpected happened
 	if loaded.runner != nil {
 		if err := loaded.runner.Ping(ctx); err != nil {
@@ -106,7 +115,7 @@ func load(ctx context.Context, workDir string, model *Model, reqOpts map[string]
 				err = fmt.Errorf("%v: this model may be incompatible with your version of Ollama. If you previously pulled this model, try updating it by running `ollama pull %s`", err, model.ShortName)
 			}
 
-			return err
+			return nil, err
 		}
 
 		loaded.Model = model
@@ -140,7 +149,7 @@ func load(ctx context.Context, workDir string, model *Model, reqOpts map[string]
 	}
 
 	loaded.expireTimer.Reset(sessionDuration)
-	return nil
+	return model, nil
 }
 
 func GenerateHandler(c *gin.Context) {
@@ -173,88 +182,135 @@ func GenerateHandler(c *gin.Context) {
 		return
 	}
 
-	model, err := GetModel(req.Model)
+	sessionDuration := defaultSessionDuration
+	model, err := load(c, req.Model, req.Options, sessionDuration)
 	if err != nil {
 		var pErr *fs.PathError
-		if errors.As(err, &pErr) {
+		switch {
+		case errors.As(err, &pErr):
 			c.JSON(http.StatusNotFound, gin.H{"error": fmt.Sprintf("model '%s' not found, try pulling it first", req.Model)})
-			return
+		case errors.Is(err, api.ErrInvalidOpts):
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		default:
+			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 		}
-		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
 		return
 	}
 
-	workDir := c.GetString("workDir")
-
-	// TODO: set this duration from the request if specified
-	sessionDuration := defaultSessionDuration
-	if err := load(c.Request.Context(), workDir, model, req.Options, sessionDuration); err != nil {
-		if errors.Is(err, api.ErrInvalidOpts) {
-			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
-			return
-		}
-		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+	// an empty request loads the model
+	if req.Prompt == "" && req.Template == "" && req.System == "" {
+		c.JSON(http.StatusOK, api.GenerateResponse{CreatedAt: time.Now().UTC(), Model: req.Model, Done: true})
 		return
 	}
 
 	checkpointLoaded := time.Now()
 
-	prompt := req.Prompt
-	if !req.Raw {
-		prompt, err = model.Prompt(req)
+	var prompt string
+	switch {
+	case req.Raw:
+		prompt = req.Prompt
+	case req.Prompt != "":
+		if req.Template != "" {
+			// override the default model template
+			model.Template = req.Template
+		}
+
+		var rebuild strings.Builder
+		if req.Context != nil {
+			// TODO: context is deprecated, at some point the context logic within this conditional should be removed
+			prevCtx, err := loaded.runner.Decode(c.Request.Context(), req.Context)
+			if err != nil {
+				c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+				return
+			}
+
+			// Remove leading spaces from prevCtx if present
+			prevCtx = strings.TrimPrefix(prevCtx, " ")
+			rebuild.WriteString(prevCtx)
+		}
+		p, err := model.Prompt(PromptVars{
+			System: req.System,
+			Prompt: req.Prompt,
+			First:  len(req.Context) == 0,
+		})
 		if err != nil {
 			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 			return
 		}
+		rebuild.WriteString(p)
+		prompt = rebuild.String()
 	}
 
 	ch := make(chan any)
+	var generated strings.Builder
 	go func() {
 		defer close(ch)
-		// an empty request loads the model
-		if req.Prompt == "" && req.Template == "" && req.System == "" {
-			ch <- api.GenerateResponse{CreatedAt: time.Now().UTC(), Model: req.Model, Done: true}
-			return
-		}
 
-		fn := func(r api.GenerateResponse) {
+		fn := func(r llm.PredictResult) {
+			// Update model expiration
 			loaded.expireAt = time.Now().Add(sessionDuration)
 			loaded.expireTimer.Reset(sessionDuration)
 
-			r.Model = req.Model
-			r.CreatedAt = time.Now().UTC()
-			if r.Done {
-				r.TotalDuration = time.Since(checkpointStart)
-				r.LoadDuration = checkpointLoaded.Sub(checkpointStart)
+			// Build up the full response
+			if _, err := generated.WriteString(r.Content); err != nil {
+				ch <- gin.H{"error": err.Error()}
+				return
 			}
 
-			if req.Raw {
-				// in raw mode the client must manage history on their own
-				r.Context = nil
+			resp := api.GenerateResponse{
+				Model:     r.Model,
+				CreatedAt: r.CreatedAt,
+				Done:      r.Done,
+				Response:  r.Content,
+				Metrics: api.Metrics{
+					TotalDuration:      r.TotalDuration,
+					LoadDuration:       r.LoadDuration,
+					PromptEvalCount:    r.PromptEvalCount,
+					PromptEvalDuration: r.PromptEvalDuration,
+					EvalCount:          r.EvalCount,
+					EvalDuration:       r.EvalDuration,
+				},
 			}
 
-			ch <- r
+			if r.Done && !req.Raw {
+				embd, err := loaded.runner.Encode(c.Request.Context(), req.Prompt+generated.String())
+				if err != nil {
+					ch <- gin.H{"error": err.Error()}
+					return
+				}
+				resp.Context = embd
+			}
+
+			ch <- resp
 		}
 
-		if err := loaded.runner.Predict(c.Request.Context(), req.Context, prompt, req.Format, fn); err != nil {
+		// Start prediction
+		predictReq := llm.PredictOpts{
+			Model:            model.Name,
+			Prompt:           prompt,
+			Format:           req.Format,
+			CheckpointStart:  checkpointStart,
+			CheckpointLoaded: checkpointLoaded,
+		}
+		if err := loaded.runner.Predict(c.Request.Context(), predictReq, fn); err != nil {
 			ch <- gin.H{"error": err.Error()}
 		}
 	}()
 
 	if req.Stream != nil && !*req.Stream {
-		var response api.GenerateResponse
-		generated := ""
+		// Wait for the channel to close
+		var r api.GenerateResponse
+		var sb strings.Builder
 		for resp := range ch {
-			if r, ok := resp.(api.GenerateResponse); ok {
-				generated += r.Response
-				response = r
-			} else {
+			var ok bool
+			if r, ok = resp.(api.GenerateResponse); !ok {
 				c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 				return
 			}
+			sb.WriteString(r.Response)
 		}
-		response.Response = generated
-		c.JSON(http.StatusOK, response)
+		r.Response = sb.String()
+		c.JSON(http.StatusOK, r)
 		return
 	}
 
@@ -281,15 +337,18 @@ func EmbeddingHandler(c *gin.Context) {
 		return
 	}
 
-	model, err := GetModel(req.Model)
+	sessionDuration := defaultSessionDuration
+	_, err = load(c, req.Model, req.Options, sessionDuration)
 	if err != nil {
-		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
-		return
-	}
-
-	workDir := c.GetString("workDir")
-	if err := load(c.Request.Context(), workDir, model, req.Options, 5*time.Minute); err != nil {
-		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		var pErr *fs.PathError
+		switch {
+		case errors.As(err, &pErr):
+			c.JSON(http.StatusNotFound, gin.H{"error": fmt.Sprintf("model '%s' not found, try pulling it first", req.Model)})
+		case errors.Is(err, api.ErrInvalidOpts):
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		default:
+			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		}
 		return
 	}
 
@@ -767,6 +826,7 @@ func Serve(ln net.Listener, allowOrigins []string) error {
 
 	r.POST("/api/pull", PullModelHandler)
 	r.POST("/api/generate", GenerateHandler)
+	r.POST("/api/chat", ChatHandler)
 	r.POST("/api/embeddings", EmbeddingHandler)
 	r.POST("/api/create", CreateModelHandler)
 	r.POST("/api/push", PushModelHandler)
@@ -860,3 +920,125 @@ func streamResponse(c *gin.Context, ch chan any) {
 		return true
 	})
 }
+
+func ChatHandler(c *gin.Context) {
+	loaded.mu.Lock()
+	defer loaded.mu.Unlock()
+
+	checkpointStart := time.Now()
+
+	var req api.ChatRequest
+	err := c.ShouldBindJSON(&req)
+	switch {
+	case errors.Is(err, io.EOF):
+		c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": "missing request body"})
+		return
+	case err != nil:
+		c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// validate the request
+	switch {
+	case req.Model == "":
+		c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": "model is required"})
+		return
+	case len(req.Format) > 0 && req.Format != "json":
+		c.AbortWithStatusJSON(http.StatusBadRequest, gin.H{"error": "format must be json"})
+		return
+	}
+
+	sessionDuration := defaultSessionDuration
+	model, err := load(c, req.Model, req.Options, sessionDuration)
+	if err != nil {
+		var pErr *fs.PathError
+		switch {
+		case errors.As(err, &pErr):
+			c.JSON(http.StatusNotFound, gin.H{"error": fmt.Sprintf("model '%s' not found, try pulling it first", req.Model)})
+		case errors.Is(err, api.ErrInvalidOpts):
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		default:
+			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		}
+		return
+	}
+
+	// an empty request loads the model
+	if len(req.Messages) == 0 {
+		c.JSON(http.StatusOK, api.ChatResponse{CreatedAt: time.Now().UTC(), Model: req.Model, Done: true})
+		return
+	}
+
+	checkpointLoaded := time.Now()
+
+	prompt, err := model.ChatPrompt(req.Messages)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	ch := make(chan any)
+
+	go func() {
+		defer close(ch)
+
+		fn := func(r llm.PredictResult) {
+			// Update model expiration
+			loaded.expireAt = time.Now().Add(sessionDuration)
+			loaded.expireTimer.Reset(sessionDuration)
+
+			resp := api.ChatResponse{
+				Model:     r.Model,
+				CreatedAt: r.CreatedAt,
+				Done:      r.Done,
+				Metrics: api.Metrics{
+					TotalDuration:      r.TotalDuration,
+					LoadDuration:       r.LoadDuration,
+					PromptEvalCount:    r.PromptEvalCount,
+					PromptEvalDuration: r.PromptEvalDuration,
+					EvalCount:          r.EvalCount,
+					EvalDuration:       r.EvalDuration,
+				},
+			}
+
+			if !r.Done {
+				resp.Message = &api.Message{Role: "assistant", Content: r.Content}
+			}
+
+			ch <- resp
+		}
+
+		// Start prediction
+		predictReq := llm.PredictOpts{
+			Model:            model.Name,
+			Prompt:           prompt,
+			Format:           req.Format,
+			CheckpointStart:  checkpointStart,
+			CheckpointLoaded: checkpointLoaded,
+		}
+		if err := loaded.runner.Predict(c.Request.Context(), predictReq, fn); err != nil {
+			ch <- gin.H{"error": err.Error()}
+		}
+	}()
+
+	if req.Stream != nil && !*req.Stream {
+		// Wait for the channel to close
+		var r api.ChatResponse
+		var sb strings.Builder
+		for resp := range ch {
+			var ok bool
+			if r, ok = resp.(api.ChatResponse); !ok {
+				c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+				return
+			}
+			if r.Message != nil {
+				sb.WriteString(r.Message.Content)
+			}
+		}
+		r.Message = &api.Message{Role: "assistant", Content: sb.String()}
+		c.JSON(http.StatusOK, r)
+		return
+	}
+
+	streamResponse(c, ch)
+}