langchain-chronoverify

LangChain tool for ChronoVerify: verify when a photo was taken and its provenance. It reads EXIF and XMP, cryptographically validates C2PA Content Credentials against the official trust lists, and runs classical pixel forensics, returning one plain-language verdict with a confidence score.

Provenance validation, not a deepfake or AI-generation detector. Verdicts are investigative triage to support human review, not proof.

Install

pip install langchain-chronoverify

Use

from langchain_chronoverify import ChronoVerifyTool

tool = ChronoVerifyTool()  # keyless: free, rate-limited public path

result = tool.invoke({"url": "https://example.com/photo.jpg"})
print(result["verdict"], result["confidence"])
# verdict is one of: provenance_confirmed, consistent, inconclusive,
# metadata_anomaly, manipulation_indicated

With an agent:

from langchain.agents import create_agent  # or your agent constructor

agent = create_agent(model, tools=[ChronoVerifyTool()])

API key (optional)

The keyless path is free and rate limited per IP. For your own quota, pass api_key="cv_live_..." or set CHRONOVERIFY_API_KEY. A free key (no card, 100 verifications per month):

curl -X POST https://chronoverify.com/v1/keys/free \
  -H "Content-Type: application/json" -d '{"email": "you@example.com"}'

Links

• Machine-readable onboarding: https://chronoverify.com/v1/onboarding
• API docs: https://chronoverify.com/method
• Response JSON Schema: https://chronoverify.com/v1/verify.schema.json
• Pricing: https://chronoverify.com/pricing