C2PA Inspector Plugin (c2pa-inspector)

An Agent Plugins v1.0.0 package providing comprehensive C2PA (Coalition for Content Provenance and Authenticity) Content Credentials inspection, verification, and batch auditing capabilities for AI agents and developers.

Disclaimer: This project is an open-source community contribution and is not an officially supported Google product.

Overview

The c2pa-inspector plugin enables autonomous agents and command-line developers to inspect media assets (images, videos, audio, and documents) for embedded C2PA provenance metadata. Built on Google Credentio, it audits cryptographic assertions, claim generators, signing certificates, and AI generation/training flags.

Key Capabilities

• Single and Multi-Asset Auditing: Inspect single files, explicit lists of paths, or entire directory trees recursively.
• Dual-Engine Execution: Uses native Google Credentio C-ABI via CFFI for complete cryptographic trust validation when available, paired with a zero-dependency pure-Python media container and JUMBF parser fallback.
• AI Provenance and Training Consent: Detects generative AI attribution (trainedAlgorithmicMedia), generative model prompts and metadata, and training/mining restrictions (c2pa.ai_generative_training, cawg.data_mining).
• Agent-Ready JSON: Generates structured JSON output optimized for tool-calling agents and automated evaluation pipelines.
• Specification Conformance: Fully conforms to the Agent Plugins v1.0.0 Specification and Agent Skills Specification.

Plugin Structure

c2pa-inspector/
├── plugin.json               # Agent Plugins v1.0.0 manifest
├── LICENSE                   # Apache 2.0 license
├── README.md                 # Documentation and usage guide
└── skills/
    └── c2pa-inspect/         # Core inspection skill
        ├── SKILL.md          # Skill definition and agent instructions
        ├── scripts/
        │   ├── inspect_c2pa.py       # Dual-engine CLI and batch inspector
        │   └── fetch_native_lib.sh   # Prebuilt libcredentio_c binary fetcher
        ├── references/
        │   ├── c2pa-spec-guide.md    # C2PA assertions, schemas, and taxonomies
        │   ├── badge-states.md       # Validation criteria and status semantics
        │   └── ai-provenance.md      # AI attribution and training-mining guide
        └── assets/
            ├── sample_crjson_v1.json # C2PA v1 sample manifest fixture
            ├── sample_crjson_v2.json # C2PA v2 sample manifest fixture
            └── sample_ai_manifest.json # AI provenance metadata fixture

Quick Start

1. Inspect a Single Asset

python3 skills/c2pa-inspect/scripts/inspect_c2pa.py sample.jpg

2. Inspect a Directory with Recursive Scanning

python3 skills/c2pa-inspect/scripts/inspect_c2pa.py --dir ./media --recursive

3. Generate Machine-Readable JSON for Agent Tooling

python3 skills/c2pa-inspect/scripts/inspect_c2pa.py asset1.jpg asset2.png --json

4. Filter by Provenance Status

# Filter only assets with AI attribution or generative provenance
python3 skills/c2pa-inspect/scripts/inspect_c2pa.py --dir ./assets --filter ai-only

# Filter only unsigned assets requiring credentials
python3 skills/c2pa-inspect/scripts/inspect_c2pa.py --dir ./assets --filter unsigned

Supported Media Formats

License

This project is licensed under the Apache 2.0 License.