Rate Limiter

Class: RateLimiterBlockV1

Source: inference.core.workflows.core_steps.flow_control.rate_limiter.v1.RateLimiterBlockV1

The Rate Limiter block controls the execution frequency of a branch within a Workflow by enforcing a cooldown period. It ensures that the connected steps do not run more frequently than a specified interval, helping to manage resource usage and prevent over-execution.

Block usage

Rate Limiter is useful when you have two blocks that are directly connected, as shown below:

--- input_a --> ┌───────────┐ ┌───────────┐ --- input_b --> │ step_1 │ --> output_a --> │ step_2 │ --- input_c --> └───────────┘ └───────────┘

If you want to throttle the Step 2 execution rate - you should apply rate limiter in between:

• keep the existing blocks configuration as is (do not change connections)

• set depends_on reference of Rate Limiter into output_a

• set next_steps reference to be a list referring to [$steps.step_2]

• adjust cooldown_seconds to specify what is the number of seconds that must be awaited before next time when step_2 is fired

Cooldown limitations

Current implementation of cooldown is limited to video processing - using this block in context of a Workflow that is run behind HTTP service (Roboflow Hosted API, Dedicated Deployment or self-hosted inference server) will have no effect for processing HTTP requests.

Type identifier

Use the following identifier in step "type" field: roboflow_core/rate_limiter@v1to add the block as as step in your workflow.

Properties

Name	Type	Description	Refs
name	str	Enter a unique identifier for this step..	❌
cooldown_seconds	float	The minimum number of seconds between allowed executions..	❌

The Refs column marks possibility to parametrise the property with dynamic values available in workflow runtime. See Bindings for more info.

Available Connections

Compatible Blocks

Check what blocks you can connect to Rate Limiter in version v1.

• inputs: Llama 3.2 Vision, SAM 3, Polygon Zone Visualization, Distance Measurement, Pixelate Visualization, Roboflow Custom Metadata, Trace Visualization, QR Code Detection, Detections Transformation, Image Threshold, Rate Limiter, Image Slicer, Icon Visualization, Stability AI Outpainting, Dynamic Zone, Clip Comparison, Model Comparison Visualization, Single-Label Classification Model, Cache Get, Stitch Images, Size Measurement, Florence-2 Model, Single-Label Classification Model, Environment Secrets Store, Relative Static Crop, Absolute Static Crop, SIFT Comparison, SAM 3, Moondream2, Florence-2 Model, LMM For Classification, Anthropic Claude, Image Blur, Stability AI Image Generation, Camera Calibration, Local File Sink, Keypoint Detection Model, VLM as Detector, First Non Empty Or Default, Detections Filter, Gaze Detection, Background Color Visualization, Keypoint Detection Model, Delta Filter, Multi-Label Classification Model, Google Gemini, Model Monitoring Inference Aggregator, Roboflow Dataset Upload, Byte Tracker, Instance Segmentation Model, VLM as Classifier, CSV Formatter, Motion Detection, Morphological Transformation, Data Aggregator, OpenAI, Barcode Detection, YOLO-World Model, JSON Parser, Clip Comparison, CogVLM, Expression, Identify Changes, CLIP Embedding Model, Path Deviation, Crop Visualization, Grid Visualization, Buffer, Bounding Rectangle, SIFT, SAM 3, Anthropic Claude, Time in Zone, Detection Offset, Qwen2.5-VL, SIFT Comparison, OpenAI, Line Counter, Detections Consensus, Cosine Similarity, Path Deviation, Blur Visualization, Perception Encoder Embedding Model, Dimension Collapse, Perspective Correction, Bounding Box Visualization, QR Code Generator, Velocity, Segment Anything 2 Model, Polygon Visualization, Dynamic Crop, Identify Outliers, LMM, OpenAI, Classification Label Visualization, Mask Visualization, Time in Zone, Google Gemini, Circle Visualization, Ellipse Visualization, Image Convert Grayscale, Time in Zone, Object Detection Model, OCR Model, SmolVLM2, Image Preprocessing, Color Visualization, Google Vision OCR, Keypoint Visualization, EasyOCR, Image Slicer, Property Definition, Line Counter, VLM as Detector, Email Notification, Detections Combine, Byte Tracker, Roboflow Dataset Upload, Overlap Filter, Triangle Visualization, Slack Notification, Halo Visualization, Detections Stabilizer, Corner Visualization, Object Detection Model, Dot Visualization, Image Contours, Detections Merge, Multi-Label Classification Model, Twilio SMS Notification, Seg Preview, Reference Path Visualization, Byte Tracker, Webhook Sink, PTZ Tracking (ONVIF).md), Detections Classes Replacement, Instance Segmentation Model, Detections Stitch, Contrast Equalization, Camera Focus, Stitch OCR Detections, Stability AI Inpainting, Line Counter Visualization, Cache Set, Template Matching, Email Notification, VLM as Classifier, OpenAI, Depth Estimation, Continue If, Background Subtraction, Label Visualization, Pixel Color Count, Dominant Color
• outputs: None

Input and Output Bindings

The available connections depend on its binding kinds. Check what binding kinds Rate Limiter in version v1 has.

Bindings

• input

  • depends_on (*): Step immediately preceding this block..
  • next_steps (step): Steps to execute if allowed by the rate limit..
  • video_reference_image (image): Reference to a video frame to use for timestamp generation (if running faster than realtime on recorded video)..

• output

Example JSON definition of step Rate Limiter in version v1

{
    "name": "<your_step_name_here>",
    "type": "roboflow_core/rate_limiter@v1",
    "cooldown_seconds": 1.0,
    "depends_on": "$steps.model",
    "next_steps": [
        "$steps.upload"
    ],
    "video_reference_image": "$inputs.image"
}