Run Model Inference on FiftyOne Datasets

Key Directives

ALWAYS follow these rules:

1. Check if dataset exists first

list_datasets()

If the dataset doesn't exist, use the fiftyone-dataset-import skill to load it first.

2. Set context before operations

set_context(dataset_name="my-dataset")

3. Launch App for inference

The App must be running to execute inference operators:

launch_app(dataset_name="my-dataset")

4. Ask user for field names

Always confirm with the user:

• Which model to use
• Label field name for predictions (e.g., predictions, detections, embeddings)

5. Close app when done

close_app()

Workflow

Step 1: Verify Dataset Exists

list_datasets()

If the dataset is not in the list:

• Ask the user for the data location
• Use the fiftyone-dataset-import skill to import the data first
• Return to this workflow after import completes

Step 2: Load Dataset and Review

set_context(dataset_name="my-dataset")
dataset_summary(name="my-dataset")

Review:

• Sample count
• Media type
• Existing label fields

Step 3: Launch App

launch_app(dataset_name="my-dataset")

Step 4: Discover and Apply Model

Ask the user about the task, model, or type of data they're using (detection, classification, segmentation, embeddings, or a specific model name); note users may give a 'tool name' (see Path B). Then determine the path:

Path A — Zoo model (most common)

ALWAYS first fetch the live model list — never assume what's available:

get_operator_schema(operator_uri="@voxel51/zoo/apply_zoo_model")

Pick the right model from the schema's model enum, then apply:

execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "<model-name-from-schema>",
        "label_field": "predictions"
    }
)

Path B — Plugin operator

If the user mentions a specific tool (e.g. CLIP similarity, SAM, a third-party model), check installed operators first:

list_operators(builtin_only=False)

Find the matching operator, inspect its schema, then execute it:

get_operator_schema(operator_uri="@org/plugin/operator")
execute_operator(operator_uri="@org/plugin/operator", params={...})

Path C — Remote / externally registered model

Check registered remote sources first:

import fiftyone.zoo as foz
foz.list_zoo_model_sources()

If the model comes from a registered remote source (GitHub repo registered via foz.registerzoomodel_source()):

execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "REMOTE",
        "source": "<github-repo-url>",
        "label_field": "predictions"
    }
)

Step 5: View Results

set_view(exists=["predictions"])

Step 6: Clean Up

close_app()

Model Discovery

ALWAYS fetch the live model list — never rely on a hardcoded list.

get_operator_schema(operator_uri="@voxel51/zoo/apply_zoo_model")

The schema returns the full set of available models at runtime. Use the model names from there directly.

For plugin-provided models or operators:

list_operators(builtin_only=False)

If a model fails with a dependency error, the response includes install_command. Offer to run it for the user.

Common Use Cases

Use Case 1: Run Object Detection

# Verify dataset exists
list_datasets()

# Set context and launch
set_context(dataset_name="my-dataset")
launch_app(dataset_name="my-dataset")

# Apply detection model
execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "faster-rcnn-resnet50-fpn-coco-torch",
        "label_field": "predictions"
    }
)

# View results
set_view(exists=["predictions"])

Use Case 2: Run Classification

set_context(dataset_name="my-dataset")
launch_app(dataset_name="my-dataset")

execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "resnet50-imagenet-torch",
        "label_field": "classification"
    }
)

set_view(exists=["classification"])

Use Case 3: Generate Embeddings

set_context(dataset_name="my-dataset")
launch_app(dataset_name="my-dataset")

execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "clip-vit-base32-torch",
        "label_field": "clip_embeddings"
    }
)

Use Case 4: Compare Ground Truth with Predictions

If dataset has existing labels:

set_context(dataset_name="my-dataset")
dataset_summary(name="my-dataset")  # Check existing fields

launch_app(dataset_name="my-dataset")

# Run inference with different field name
execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "yolov8m-coco-torch",
        "label_field": "predictions"  # Different from ground_truth
    }
)

# View both fields to compare
set_view(exists=["ground_truth", "predictions"])

Use Case 5: Run Multiple Models

set_context(dataset_name="my-dataset")
launch_app(dataset_name="my-dataset")

# Run detection
execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "yolov8n-coco-torch",
        "label_field": "detections"
    }
)

# Run classification
execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "resnet50-imagenet-torch",
        "label_field": "classification"
    }
)

# Run embeddings
execute_operator(
    operator_uri="@voxel51/zoo/apply_zoo_model",
    params={
        "tab": "BUILTIN",
        "model": "clip-vit-base32-torch",
        "label_field": "embeddings"
    }
)

Troubleshooting

Error: "Dataset not found"

• Use list_datasets() to see available datasets
• Use the fiftyone-dataset-import skill to import data first

Error: "Model not found"

• Run getoperatorschema(operatoruri="@voxel51/zoo/applyzoo_model") to get the current live model list and pick the correct name

Error: "Missing dependency" (e.g., ultralytics, segment-anything)

• The MCP server detects missing dependencies
• Response includes missingpackage and installcommand
• Install the required package: pip install <package>
• Restart MCP server after installing

Inference is slow

• Use smaller model variant (e.g., yolov8n instead of yolov8x)
• Use delegated execution for large datasets
• Consider filtering to a view first

Out of memory

• Reduce batch size
• Use smaller model variant
• Process dataset in chunks using views

Best Practices

1. Use descriptive field names - predictions, yolodetections, clipembeddings
2. Don't overwrite ground truth - Use different field names for predictions
3. Start with fast models - Use nano/small variants first, upgrade if needed
4. Check existing fields - Use dataset_summary() before running inference
5. Filter first for testing - Test on a small view before processing full dataset

Resources

• FiftyOne Model Zoo
• Applying Models Guide
• Zoo Models API