jinfer

name: jinfer description: Use jinfer to infer JSON schema from JSON files. Trigger when user wants to understand JSON structure, generate JSON Schema, or inspect the shape of JSON data.

jinfer — JSON Schema Inference

jinfer is a zero-dependency CLI tool and Python library that instantly infers structured schemas from any JSON file. It is installed on this machine and available as the jinfer command. Requires Python 3.10+. Installed via uv tool install jinfer.

When to use

Use jinfer when the user:

• Asks about the structure or shape of a JSON file
• Wants to generate a JSON Schema from sample data
• Needs to inspect or understand what fields and types exist in JSON data
• Has a JSON file and wants a quick overview of its contents
• Wants to validate or document the structure of JSON output

CLI usage

Basic tree view (pretty-printed schema summary):

jinfer <file.json>

Output as JSON Schema (draft-07):

jinfer <file.json> -f json

Limit traversal depth (useful for large or deeply nested files):

jinfer <file.json> -d 3

Pipe from stdin:

cat file.json | jinfer -

Save output to a file:

jinfer <file.json> -f json -o schema.json

Key flags

Python library usage

from jinfer import infer_schema, format_schema, generate_json_schema

# Infer schema from a Python object
schema = infer_schema(data)

# Pretty-print as a tree
print(format_schema(schema))

# Generate JSON Schema draft-07 dict
json_schema = generate_json_schema(schema)

Tips

• For large JSON files, use -d to limit depth first, then increase as needed.
• Use -f json when you need a machine-readable schema for validation or documentation.
• The tree format is best for quick human inspection of structure.
• When piping, use - as the filename to read from stdin.