Lemonade API
We have designed a set of Lemonade-specific endpoints to enable client applications by extending the existing cloud-focused APIs (e.g., OpenAI). These extensions allow for a greater degree of UI/UX responsiveness in native applications by allowing applications to:
- Download models at setup time.
- Pre-load models at UI-loading-time, as opposed to completion-request time.
- Unload models to save memory space.
- Understand system resources and state to make dynamic choices.
| Method | Endpoint | Description |
|---|---|---|
POST |
/v1/pull |
Install a model |
GET |
/v1/downloads |
List server-owned model download jobs |
POST |
/v1/downloads/control |
Pause, cancel, or remove server-owned model download jobs |
GET |
/v1/pull/variants |
Enumerate GGUF variants for a Hugging Face checkpoint |
POST |
/v1/delete |
Delete a model |
POST |
/v1/load |
Load a model |
POST |
/v1/unload |
Unload a model |
GET |
/v1/health |
Check server status, such as models loaded |
GET |
/v1/stats |
Performance statistics from the last request |
GET |
/v1/system-info |
System information and device enumeration |
POST |
/v1/install |
Install or update a backend |
POST |
/v1/uninstall |
Remove a backend |
WS |
/logs/stream |
Log Streaming |
GET |
/live |
Check server liveness for load balancers and orchestrators |
GET |
/metrics |
Prometheus metrics scrape endpoint |
POST /v1/pull
Register and install models for use with Lemonade Server.
Parameters
The Lemonade Server built-in model registry has a collection of model names that can be pulled and loaded. The pull endpoint can install any registered model, and it can also register-then-install any model available on Hugging Face.
Common Parameters
| Parameter | Required | Description |
|---|---|---|
stream |
No | If true, returns Server-Sent Events (SSE) with download progress. Defaults to false. |
subscribe |
No | Only applies when stream=true. If false, the server starts a background model download job and returns a JSON snapshot immediately instead of keeping the HTTP response subscribed to SSE progress. Defaults to true for backwards compatibility. |
Install a Model that is Already Registered
| Parameter | Required | Description |
|---|---|---|
model_name |
Yes | Lemonade Server model name to install. |
Example request:
curl -X POST http://localhost:13305/v1/pull \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF"
}'
Response format:
{
"status":"success",
"message":"Installed model: Qwen3-0.6B-GGUF"
}
In case of an error, the status will be error and the message will contain the error message.
Register and Install a Model
Registration will place an entry for that model in the user_models.json file, which is located in the user's Lemonade cache (default: ~/.cache/lemonade). Then, the model will be installed. Once the model is registered and installed, it will show up in the models endpoint alongside the built-in models and can be loaded.
The recipe field defines which software framework and device will be used to load and run the model.
Note: the
model_namefor registering a new model must use theusernamespace, to prevent collisions with built-in models. For example,user.Phi-4-Mini-GGUF.
| Parameter | Required | Description |
|---|---|---|
model_name |
Yes | Namespaced Lemonade Server model name to register and install. |
checkpoint |
Yes | HuggingFace checkpoint to install. |
recipe |
Yes | Lemonade API recipe to load the model with. |
reasoning |
No | Whether the model is a reasoning model, like DeepSeek (default: false). Adds 'reasoning' label. |
vision |
No | Whether the model has vision capabilities for processing images (default: false). Adds 'vision' label. |
embedding |
No | Whether the model is an embedding model (default: false). Adds 'embeddings' label. |
reranking |
No | Whether the model is a reranking model (default: false). Adds 'reranking' label. |
mmproj |
No | Multimodal Projector (mmproj) file to use for vision models. |
Example request:
curl -X POST http://localhost:13305/v1/pull \
-H "Content-Type: application/json" \
-d '{
"model_name": "user.Phi-4-Mini-GGUF",
"checkpoint": "unsloth/Phi-4-mini-instruct-GGUF:Q4_K_M",
"recipe": "llamacpp"
}'
Response format:
{
"status":"success",
"message":"Installed model: user.Phi-4-Mini-GGUF"
}
In case of an error, the status will be error and the message will contain the error message.
Register an Omni-Model
An omni collection is a collection type that bundles several already-registered models into a single entry that can be loaded, pulled, or deleted as a unit. Use recipe: "collection.omni" with a components array instead of checkpoint.
| Parameter | Required | Description |
|---|---|---|
model_name |
Yes | Namespaced model name, e.g. user.MyKit. |
recipe |
Yes | Must be "collection.omni". |
components |
Yes | Non-empty array of registered model names. Each entry must already exist in the registry (built-in or a previously registered user.* model). |
Components do not need to be downloaded already — any not-yet-downloaded components are pulled by the same call. Deleting the collection removes only the collection entry; components stay on disk.
Example request:
curl -X POST http://localhost:13305/v1/pull \
-H "Content-Type: application/json" \
-d '{
"model_name": "user.MyKit",
"recipe": "collection.omni",
"components": ["Qwen3-0.6B-GGUF", "Whisper-Tiny", "SD-Turbo"]
}'
Streaming Response (stream=true)
When stream=true, the endpoint returns Server-Sent Events with real-time download progress:
event: progress
data: {"file":"model.gguf","file_index":1,"total_files":2,"bytes_downloaded":1073741824,"bytes_total":2684354560,"percent":40}
event: progress
data: {"file":"config.json","file_index":2,"total_files":2,"bytes_downloaded":1024,"bytes_total":1024,"percent":100}
event: complete
data: {"file_index":2,"total_files":2,"percent":100}
Event Types:
| Event | Description |
|---|---|
progress |
Sent during download with current file and byte progress |
complete |
Sent when all files are downloaded successfully |
error |
Sent if download fails, with error field containing the message |
Server-owned download mode (stream=true, subscribe=false)
By default, stream=true keeps the /v1/pull HTTP response subscribed to Server-Sent Events until the download finishes. Clients that need download state to survive a renderer reload, tab close, or reconnect can also send subscribe=false.
When stream=true and subscribe=false, /v1/pull starts a server-owned model download job and returns a JSON snapshot immediately. The job continues on the server. Clients can poll GET /v1/downloads to restore progress and can use POST /v1/downloads/control to pause, cancel, or remove the job.
Example request:
curl -X POST http://localhost:13305/v1/pull \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF",
"stream": true,
"subscribe": false
}'
Example response:
{
"id": "model:Qwen3-0.6B-GGUF",
"type": "model",
"model_name": "Qwen3-0.6B-GGUF",
"status": "downloading",
"running": true,
"file": "",
"file_index": 0,
"total_files": 0,
"bytes_downloaded": 0,
"bytes_total": 0,
"total_download_size": 0,
"bytes_previously_downloaded": 0,
"completed_files_bytes": 0,
"cumulative_bytes_downloaded": 0,
"overall_bytes_downloaded": 0,
"percent": 0,
"complete": false
}
GET /v1/downloads
List server-owned model download jobs that were started with POST /v1/pull using stream=true and subscribe=false.
This endpoint is intended for clients that need to restore download-manager state after a reload or reconnect. Active, paused, cancelled, and errored jobs remain visible until the client removes them. Completed jobs remain visible briefly so clients can observe completion and refresh model state.
Example request
curl http://localhost:13305/v1/downloads
Response format
[
{
"id": "model:Qwen3-0.6B-GGUF",
"type": "model",
"model_name": "Qwen3-0.6B-GGUF",
"status": "downloading",
"running": true,
"file": "model.gguf",
"file_index": 1,
"total_files": 2,
"bytes_downloaded": 1073741824,
"bytes_total": 2684354560,
"total_download_size": 2684355584,
"bytes_previously_downloaded": 0,
"completed_files_bytes": 0,
"cumulative_bytes_downloaded": 1073741824,
"overall_bytes_downloaded": 1073741824,
"percent": 40,
"complete": false
}
]
Download job fields
| Field | Description |
|---|---|
id |
Stable download id. Model downloads use model:<model_name>. |
type |
Download type. Currently model for server-owned jobs. |
model_name |
Lemonade model name associated with the job. |
status |
Current state: downloading, paused, cancelled, completed, or error. |
running |
Whether the download worker is still active. A terminal-looking status may still have running=true while the worker is releasing resources. |
file, file_index, total_files |
Current file progress within the download. |
bytes_downloaded, bytes_total, percent |
Current-file byte progress as reported by the downloader. |
total_download_size |
Total expected bytes across all files when known. |
bytes_previously_downloaded |
Bytes already present on disk for the current file when resuming or skipping existing data. |
completed_files_bytes |
Bytes from files completed before the current file. |
cumulative_bytes_downloaded, overall_bytes_downloaded |
Total bytes downloaded across the whole job. overall_bytes_downloaded is kept as a compatibility alias. |
complete |
true when the download completed successfully. |
error |
Error message, present only for failed jobs. |
POST /v1/downloads/control
Control a server-owned model download job.
Parameters
| Parameter | Required | Description |
|---|---|---|
id |
Yes | Download id returned by POST /v1/pull or GET /v1/downloads, for example model:Qwen3-0.6B-GGUF. |
action |
Yes | One of pause, cancel, or remove. |
Actions
| Action | Description |
|---|---|
pause |
Requests the worker to stop and keeps the job visible as paused. The worker may briefly report running=true while it unwinds. |
cancel |
Requests the worker to stop and marks the job as cancelled. Clients should wait for running=false before deleting partial files. |
remove |
Removes a stopped job from the server registry. If the worker is still running, the server keeps the job visible and treats the request as a cancel request until the worker stops. |
Example request
curl -X POST http://localhost:13305/v1/downloads/control \
-H "Content-Type: application/json" \
-d '{
"id": "model:Qwen3-0.6B-GGUF",
"action": "pause"
}'
Response format
For pause and cancel, the endpoint returns the latest job snapshot:
{
"id": "model:Qwen3-0.6B-GGUF",
"type": "model",
"model_name": "Qwen3-0.6B-GGUF",
"status": "paused",
"running": false,
"file": "model.gguf",
"file_index": 1,
"total_files": 2,
"bytes_downloaded": 1073741824,
"bytes_total": 2684354560,
"percent": 40,
"complete": false
}
For remove, the endpoint returns:
{"status":"ok"}
If the job is already missing and action is remove, the endpoint returns:
{"status":"ok","missing":true}
GET /v1/pull/variants
Inspect a Hugging Face GGUF repository and enumerate the variants (quantizations and sharded folder groups) available for installation. Used by the lemonade pull <owner/repo> CLI flow and by the desktop app's model search to auto-populate the install form. The endpoint reads only public Hugging Face metadata; if the HF_TOKEN environment variable is set on the server, it is forwarded as a bearer token to access gated repositories.
Parameters
| Parameter | Required | Description |
|---|---|---|
checkpoint |
Yes | Hugging Face repo id, e.g. unsloth/Qwen3-8B-GGUF. Passed as a query string. |
Example request:
curl 'http://localhost:13305/v1/pull/variants?checkpoint=unsloth/Qwen3-8B-GGUF'
Response
{
"checkpoint": "unsloth/Qwen3-8B-GGUF",
"recipe": "llamacpp",
"suggested_name": "Qwen3-8B-GGUF",
"suggested_labels": ["vision"],
"mmproj_files": ["mmproj-model-f16.gguf"],
"variants": [
{
"name": "Q4_K_M",
"primary_file": "Qwen3-8B-Q4_K_M.gguf",
"files": ["Qwen3-8B-Q4_K_M.gguf"],
"sharded": false,
"size_bytes": 4920000000
},
{
"name": "Q8_0",
"primary_file": "Q8_0/Qwen3-8B-Q8_0-00001-of-00002.gguf",
"files": ["Q8_0/Qwen3-8B-Q8_0-00001-of-00002.gguf", "Q8_0/Qwen3-8B-Q8_0-00002-of-00002.gguf"],
"sharded": true,
"size_bytes": 8500000000
}
]
}
| Field | Description |
|---|---|
checkpoint |
Echoed input. |
recipe |
Suggested recipe (always llamacpp today; future expansion may return other values). |
suggested_name |
Repo id stripped of the owner/ prefix; suitable for use as the user.<name> model name. |
suggested_labels |
Inferred labels — vision if any mmproj-*.gguf files exist, plus embeddings/reranking if those substrings appear in the repo id. |
mmproj_files |
Bare filenames of mmproj-*.gguf files in the repo; the first one should be passed as mmproj to /v1/pull for vision models. |
variants[] |
Top quantizations for the repo, capped at 5. Each entry has name (e.g. Q4_K_M, UD-Q4_K_XL), primary_file, files, sharded, and size_bytes (from the HF ?blobs=true listing). Ranked by frequency of use in server_models.json (Q4_K_M, UD-Q4_K_XL, Q8_0, Q4_0 first, everything else sorted lexicographically). The CLI lemonade pull menu adds a free-text "Other" option for quants outside the top 5. |
Error responses
| Status | Cause |
|---|---|
| 400 | checkpoint query parameter missing or malformed (must contain /). |
| 404 | Hugging Face returned 404 for the checkpoint. |
| 500 | Other transport or parsing failures; the response body contains an error message. |
POST /v1/delete
Delete a model by removing it from local storage. If the model is currently loaded, it will be unloaded first.
Note: deleting a collection (
recipe: "collection.omni") removes only the collection entry fromuser_models.json; its components stay on disk. Delete the components individually if you want to free their disk space.
Parameters
| Parameter | Required | Description |
|---|---|---|
model_name |
Yes | Lemonade Server model name to delete. |
Example request:
curl -X POST http://localhost:13305/v1/delete \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF"
}'
Response format:
{
"status":"success",
"message":"Deleted model: Qwen3-0.6B-GGUF"
}
In case of an error, the status will be error and the message will contain the error message.
POST /v1/load
Explicitly load a registered model into memory. This is useful to ensure that the model is loaded before you make a request. Installs the model if necessary.
Note: loading a collection (
recipe: "collection.omni") loads each of its components in turn. Per-model options likectx_sizeorllamacpp_backendare not forwarded to components — set them on each component's ownrecipe_options.jsonentry instead.
Parameters
| Parameter | Required | Applies to | Description |
|---|---|---|---|
model_name |
Yes | All | Lemonade Server model name to load. |
save_options |
No | All | Boolean. If true, saves recipe options to recipe_options.json. Any previously stored value for model_name is replaced. |
ctx_size |
No | llamacpp, flm, ryzenai-llm | Context size for the model. Overrides the default value. |
llamacpp_backend |
No | llamacpp | LlamaCpp backend to use (vulkan, rocm, metal or cpu). |
llamacpp_args |
No | llamacpp | Custom arguments to pass to llama-server. The following are NOT allowed: -m, --port, --ctx-size, -ngl, --jinja, --mmproj, --embeddings, --reranking. |
whispercpp_backend |
No | whispercpp | WhisperCpp backend: npu or cpu on Windows; cpu or vulkan on Linux. Default is npu if supported. |
whispercpp_args |
No | whispercpp | Custom arguments to pass to whisper-server. The following are NOT allowed: -m, --model, --port. Example: --convert. |
steps |
No | sd-cpp | Number of inference steps for image generation. Default: 20. |
cfg_scale |
No | sd-cpp | Classifier-free guidance scale for image generation. Default: 7.0. |
width |
No | sd-cpp | Image width in pixels. Default: 512. |
height |
No | sd-cpp | Image height in pixels. Default: 512. |
merge_args |
No | All | Boolean. If true (default), *_args values from global config and per-model config are merged (per-model takes priority). If false, per-model *_args replace global *_args entirely. |
Setting Priority:
When loading a model, settings are applied in this priority order:
1. Values explicitly passed in the load request (highest priority)
2. Per-model values configurable in recipe_options.json (see below for details)
3. Values from environment variables or server startup arguments (see Server Configuration)
4. Default hardcoded values in lemond (lowest priority)
Per-model options
You can configure recipe-specific options on a per-model basis. Lemonade manages a file called recipe_options.json in the user's Lemonade cache (default: ~/.cache/lemonade). The available options depend on the model's recipe:
{
"user.Qwen2.5-Coder-1.5B-Instruct": {
"ctx_size": 16384,
"llamacpp_backend": "vulkan",
"llamacpp_args": "-np 2 -kvu"
},
"Qwen3-Coder-30B-A3B-Instruct-GGUF" : {
"llamacpp_backend": "rocm"
},
"whisper-large-v3-turbo-q8_0.bin": {
"whispercpp_backend": "npu",
"whispercpp_args": "--convert"
}
}
Note that model names include any applicable prefix, such as user. and extra..
Example requests
Basic load:
curl -X POST http://localhost:13305/v1/load \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF"
}'
Load with custom settings:
curl -X POST http://localhost:13305/v1/load \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF",
"ctx_size": 8192,
"llamacpp_backend": "rocm",
"llamacpp_args": "--flash-attn on --no-mmap"
}'
Load and save settings:
curl -X POST http://localhost:13305/v1/load \
-H "Content-Type: application/json" \
-d '{
"model_name": "Qwen3-0.6B-GGUF",
"ctx_size": 8192,
"llamacpp_backend": "vulkan",
"llamacpp_args": "--no-context-shift --no-mmap",
"save_options": true
}'
Load a Whisper model with NPU backend and conversion enabled:
curl -X POST http://localhost:13305/v1/load \
-H "Content-Type: application/json" \
-d '{
"model_name": "whisper-large-v3-turbo-q8_0.bin",
"whispercpp_backend": "npu",
"whispercpp_args": "--convert"
}'
Load an image generation model with custom settings:
curl -X POST http://localhost:13305/v1/load \
-H "Content-Type: application/json" \
-d '{
"model_name": "sd-turbo",
"steps": 4,
"cfg_scale": 1.0,
"width": 512,
"height": 512
}'
Response format
{
"status":"success",
"message":"Loaded model: Qwen3-0.6B-GGUF"
}
In case of an error, the status will be error and the message will contain the error message.
POST /v1/unload
Explicitly unload a model from memory. This is useful to free up memory while still leaving the server process running (which takes minimal resources but a few seconds to start).
Parameters
| Parameter | Required | Description |
|---|---|---|
model_name |
No | Name of the specific model to unload. If not provided, all loaded models will be unloaded. |
Example requests
Unload a specific model:
curl -X POST http://localhost:13305/v1/unload \
-H "Content-Type: application/json" \
-d '{"model_name": "Qwen3-0.6B-GGUF"}'
Unload all models:
curl -X POST http://localhost:13305/v1/unload
Response format
Success response:
{
"status": "success",
"message": "Model unloaded successfully"
}
Error response (model not found):
{
"status": "error",
"message": "Model not found: Qwen3-0.6B-GGUF"
}
In case of an error, the status will be error and the message will contain the error message.
GET /v1/health
Check the health of the server. This endpoint returns information about loaded models.
Parameters
This endpoint does not take any parameters.
Example request
curl http://localhost:13305/v1/health
Response format
{
"status": "ok",
"version":"9.3.3",
"websocket_port":9000,
"model_loaded": "Llama-3.2-1B-Instruct-Hybrid",
"all_models_loaded": [
{
"model_name": "Llama-3.2-1B-Instruct-Hybrid",
"checkpoint": "amd/Llama-3.2-1B-Instruct-awq-g128-int4-asym-fp16-onnx-hybrid",
"last_use": 1732123456.789,
"type": "llm",
"device": "gpu npu",
"recipe": "ryzenai-llm",
"pid": 12345,
"recipe_options": {
"ctx_size": 4096
},
"backend_url": "http://127.0.0.1:8001/v1"
},
{
"model_name": "nomic-embed-text-v1-GGUF",
"checkpoint": "nomic-ai/nomic-embed-text-v1-GGUF:Q4_K_S",
"last_use": 1732123450.123,
"type": "embedding",
"device": "gpu",
"recipe": "llamacpp",
"pid": 12346,
"recipe_options": {
"ctx_size": 8192,
"llamacpp_args": "--no-mmap",
"llamacpp_backend": "rocm"
},
"backend_url": "http://127.0.0.1:8002/v1"
}
],
"max_models": {
"transcription":1,
"embedding":1,
"image":1,
"llm":1,
"reranking":1,
"tts":1
}
}
Field Descriptions:
status- Server health status, always"ok"version- Version number of Lemonade Servermodel_loaded- Model name of the most recently accessed modelall_models_loaded- Array of all currently loaded models with details:model_name- Name of the loaded modelcheckpoint- Full checkpoint identifierlast_use- Unix timestamp of last access (load or inference)type- Model type:"llm","embedding","reranking","transcription","image", or"tts"device- Space-separated device list:"cpu","gpu","npu", or combinations like"gpu npu"backend_url- URL of the backend server process handling this model (useful for debugging)pid- The Process ID (PID) of the backend engine handling this modelrecipe- Backend/device recipe used to load the model (e.g.,"ryzenai-llm","llamacpp","flm")recipe_options- Options used to load the model (e.g.,"ctx_size","llamacpp_backend","llamacpp_args","whispercpp_args")max_models- Maximum number of models that can be loaded simultaneously per type (set viamax_loaded_modelsin Server Configuration):llm- Maximum LLM/chat modelsembedding- Maximum embedding modelsreranking- Maximum reranking modelstranscription- Maximum speech-to-text modelsimage- Maximum image modelstts- Maximum text-to-speech modelswebsocket_port- (optional) Port of the WebSocket server for the Realtime Audio Transcription API and Log Streaming API. Only present when the WebSocket server is running. The port is OS-assigned or set via--websocket-port.
GET /v1/stats
Performance statistics from the last request.
Parameters
This endpoint does not take any parameters.
Example request
curl http://localhost:13305/v1/stats
Response format
{
"time_to_first_token": 2.14,
"tokens_per_second": 33.33,
"input_tokens": 128,
"output_tokens": 5,
"prompt_tokens": 9
}
Field Descriptions:
time_to_first_token- Time in seconds until the first token was generatedtokens_per_second- Generation speed in tokens per secondinput_tokens- Number of tokens processedoutput_tokens- Number of tokens generatedprompt_tokens- Total prompt tokens including cached tokens
GET /metrics
Prometheus scrape endpoint for Lemonade Server. The endpoint returns Prometheus text exposition format and is intended to be scraped by Prometheus, not by Grafana directly.
Unlike most Lemonade API endpoints, /metrics is root-level only. It is not mounted under /api/v0/, /api/v1/, /v0/, or /v1/.
HEAD /metrics is also supported and returns 200 OK with an empty body.
Authentication
If LEMONADE_API_KEY is set, /metrics requires bearer authentication. Either the regular API key or LEMONADE_ADMIN_API_KEY is accepted.
If only LEMONADE_ADMIN_API_KEY is set and LEMONADE_API_KEY is unset, /metrics is accessible without authentication, matching regular API endpoint behavior.
Polling and Refresh Rate
The /metrics endpoint has no internal refresh timer. It renders the latest server state at the moment it is scraped.
Polling frequency is configured in Prometheus via scrape_interval, for example:
global:
scrape_interval: 10s
Grafana queries Prometheus. Grafana's dashboard refresh controls how often panels query Prometheus, but it does not control how often Prometheus scrapes Lemonade.
Example request
curl http://localhost:13305/metrics
With API-key auth:
curl http://localhost:13305/metrics \
-H "Authorization: Bearer $LEMONADE_API_KEY"
Response format
The response uses Prometheus text exposition format:
# HELP lemonade_server_up Whether the Lemonade server is running.
# TYPE lemonade_server_up gauge
lemonade_server_up 1
# HELP lemonade_server_info Lemonade server build information.
# TYPE lemonade_server_info gauge
lemonade_server_info{version="10.4.0"} 1
Content type:
text/plain; version=0.0.4; charset=utf-8
Lemonade Metric Families
The authoritative metric-family list is generated by the /metrics implementation in src/cpp/server/server.cpp. Search for handle_metrics and metrics.describe(...) to see the current names, types, labels, and descriptions.
Unsupported, unavailable, null, NaN, and infinity values are omitted rather than emitted as samples.
llama.cpp Backend Metrics
When a loaded model uses the llamacpp recipe, Lemonade makes a best-effort scrape of the loaded backend process's private /metrics endpoint. Backend scrape failures do not fail the Lemonade /metrics response.
Scraped llama.cpp metrics are normalized under the lemonade_llamacpp_* prefix and labeled with the same Lemonade model metadata used by lemonade_model_info.
Lemonade starts llama.cpp backends with metrics enabled so these backend metrics are available whenever the backend supports them.
GET /v1/system-info
System information endpoint that provides complete hardware details and device enumeration.
Example request
curl "http://localhost:13305/v1/system-info"
Response format
{
"OS Version": "Windows-10-10.0.26100-SP0",
"Processor": "AMD Ryzen AI 9 HX 375 w/ Radeon 890M",
"Physical Memory": "32.0 GB",
"OEM System": "ASUS Zenbook S 16",
"BIOS Version": "1.0.0",
"CPU Max Clock": "5100 MHz",
"Windows Power Setting": "Balanced",
"devices": {
"cpu": {
"name": "AMD Ryzen AI 9 HX 375 w/ Radeon 890M",
"cores": 12,
"threads": 24,
"available": true,
"family": "x86_64"
},
"amd_gpu": [
{
"name": "AMD Radeon(TM) 890M Graphics",
"vram_gb": 0.5,
"available": true,
"family": "gfx1150"
}
],
"amd_npu": {
"name": "AMD Ryzen AI 9 HX 375 w/ Radeon 890M",
"power_mode": "Default",
"available": true,
"family": "XDNA2"
}
},
"recipes": {
"llamacpp": {
"default_backend": "vulkan",
"backends": {
"vulkan": {
"devices": ["cpu", "amd_gpu"],
"state": "installed",
"message": "",
"action": "",
"version": "b7869"
},
"rocm": {
"devices": ["amd_gpu"],
"state": "installable",
"message": "Backend is supported but not installed.",
"action": "lemonade backends install llamacpp:rocm"
},
"metal": {
"devices": [],
"state": "unsupported",
"message": "Requires macOS",
"action": ""
},
"cpu": {
"devices": ["cpu"],
"state": "update_required",
"message": "Backend update is required before use.",
"action": "lemonade backends install llamacpp:cpu"
}
}
},
"whispercpp": {
"default_backend": "default",
"backends": {
"default": {
"devices": ["cpu"],
"state": "installable",
"message": "Backend is supported but not installed.",
"action": "lemonade backends install whispercpp:default"
}
}
},
"sd-cpp": {
"default_backend": "default",
"backends": {
"default": {
"devices": ["cpu"],
"state": "installable",
"message": "Backend is supported but not installed.",
"action": "lemonade backends install sd-cpp:default"
}
}
},
"flm": {
"default_backend": "default",
"backends": {
"default": {
"devices": ["amd_npu"],
"state": "installed",
"message": "",
"action": "",
"version": "1.2.0"
}
}
},
"ryzenai-llm": {
"default_backend": "default",
"backends": {
"default": {
"devices": ["amd_npu"],
"state": "installed",
"message": "",
"action": ""
}
}
}
}
}
Field Descriptions:
- System fields:
OS Version- Operating system name and versionProcessor- CPU model namePhysical Memory- Total RAMOEM System- System/laptop model name (Windows only)BIOS Version- BIOS information (Windows only)CPU Max Clock- Maximum CPU clock speed (Windows only)-
Windows Power Setting- Current power plan (Windows only) -
devices- Hardware devices detected on the system (no software/support information) cpu- CPU information (name, cores, threads)amd_gpu- Array of AMD GPUs, both integrated and discrete (if present)nvidia_gpu- Array of NVIDIA GPUs (if present)-
amd_npu- AMD NPU device (if present) -
recipes- Software recipes and their backend support status - Each recipe (e.g.,
llamacpp,whispercpp,flm) contains:default_backend- Preferred backend selected by server policy for this system (present when at least one backend is notunsupported)backends- Available backends for this recipe- Each backend contains:
devices- List of devices on this system that support this backend (empty if not supported)state- Backend lifecycle state:unsupported,installable,update_required, orinstalledmessage- Human-readable status text for GUI and CLI users. Required forunsupported,installable, andupdate_required; empty forinstalled.action- Actionable user instruction string. For install/update cases this is typically an exact CLI command; for other states it may be empty or another actionable value (for example, a URL).version- Installed or configured backend version (when available)
POST /v1/install
Install or update a backend for a specific recipe/backend pair. If the backend is already installed but outdated, this endpoint updates it to the configured version.
Parameters
| Parameter | Required | Description |
|---|---|---|
recipe |
Yes | Recipe name (for example, llamacpp, flm, whispercpp, sd-cpp, ryzenai-llm) |
backend |
Yes | Backend name within the recipe (for example, vulkan, rocm, cpu, default) |
stream |
No | If true, returns Server-Sent Events with progress. Defaults to false. |
force |
No | If true, bypasses hardware filtering for unsupported backends and attempts installation anyway. Defaults to false. |
Example request
curl -X POST http://localhost:13305/v1/install \
-H "Content-Type: application/json" \
-d '{
"recipe": "llamacpp",
"backend": "vulkan",
"stream": false
}'
Response format
{
"status":"success",
"recipe":"llamacpp",
"backend":"vulkan"
}
In case of an error, returns an error field with details.
POST /v1/uninstall
Uninstall a backend for a specific recipe/backend pair. If loaded models are using that backend, they are unloaded first.
Parameters
| Parameter | Required | Description |
|---|---|---|
recipe |
Yes | Recipe name |
backend |
Yes | Backend name |
Example request
curl -X POST http://localhost:13305/v1/uninstall \
-H "Content-Type: application/json" \
-d '{
"recipe": "llamacpp",
"backend": "vulkan"
}'
Response format
{
"status":"success",
"recipe":"llamacpp",
"backend":"vulkan"
}
In case of an error, returns an error field with details.
Log Streaming API (WebSocket)
Stream server logs over WebSocket. Clients connect, send a subscribe message, and receive a snapshot of recent log history followed by live log entries as they occur.
Connection
The WebSocket server shares the same port as the Realtime Audio Transcription API. Discover the port via the /v1/health endpoint (websocket_port field), then connect:
ws://localhost:<websocket_port>/logs/stream
After connecting, send a logs.subscribe message to start receiving logs.
Client → Server Messages
| Message Type | Description |
|---|---|
logs.subscribe |
Subscribe to log stream. Optional after_seq field to resume from a specific sequence number. |
Server → Client Messages
| Message Type | Description |
|---|---|
logs.snapshot |
Initial batch of retained log entries (up to 5000). Sent once after subscribing. |
logs.entry |
A single live log entry. Sent as new log lines are emitted. |
error |
Error message (e.g., invalid subscribe request). |
Example: Subscribe to Logs
Subscribe from the beginning (full backlog):
{
"type": "logs.subscribe",
"after_seq": null
}
Resume after a known sequence number (e.g., on reconnect):
{
"type": "logs.subscribe",
"after_seq": 1042
}
Example: Snapshot Response
{
"type": "logs.snapshot",
"entries": [
{
"seq": 1,
"timestamp": "2025-03-30 14:22:01.123",
"severity": "Info",
"tag": "Server",
"line": "2025-03-30 14:22:01.123 [Info] (Server) Starting Lemonade Server..."
}
]
}
Example: Live Entry
{
"type": "logs.entry",
"entry": {
"seq": 1043,
"timestamp": "2025-03-30 14:22:05.456",
"severity": "Info",
"tag": "Router",
"line": "2025-03-30 14:22:05.456 [Info] (Router) Model loaded successfully"
}
}
Log Entry Fields
| Field | Type | Description |
|---|---|---|
seq |
integer | Monotonically increasing sequence number. Use for dedup and resume. |
timestamp |
string | Formatted timestamp from the log system. |
severity |
string | Log level: Trace, Debug, Info, Warning, Error, Fatal. |
tag |
string | Log source tag (e.g., Server, Router, component name). |
line |
string | The full formatted log line. |
Integration Notes
- Reconnection: Track the last
seqreceived and pass it asafter_seqon reconnect to avoid duplicate entries. - Backlog: The server retains up to 5000 recent log entries. The snapshot may be smaller if fewer entries exist.
- Platform availability: WebSocket log streaming is available on all platforms (Windows, Linux, and macOS).
GET /live
Lightweight liveness probe for load balancers and orchestrators. Unlike /v1/health, this endpoint does no work beyond confirming the process is up — it does not inspect loaded models or backends — so it is safe to poll at high frequency. HEAD /live is also supported and returns 200 OK with an empty body.
Unlike the other endpoints on this page, /live is not versioned and is not mounted under the /api/v0/, /api/v1/, /v0/, /v1/ prefixes.
Example request
curl http://localhost:13305/live
Response format
{"status":"ok"}