See what is declared.
Read the card’s core fields and advertised settings, from interfaces to authentication declarations.
A2A Agent Card Scanner Public beta
Check your card.
Fix what matters.
Find issues in your A2A Agent Card before an integration. Get a fix checklist, recheck your changes, and take the same checks into CI.
Free public beta · No signup needed · Open-source core ↗
Inspect a card Shipping an update? Compare two Agent Cards locally →Found a problem? Get a corrected card →
01 / Inspect an Agent Card
No agent tasks invoked
Reading the card. Checking the evidence.
One inspection, up to 20 seconds.
Developer pilot · Optional
Building with A2A?
Help shape the scanner.
Bring a card you build or plan to integrate. Tell us which findings helped, what was unclear, and what check you need next.
We’re working toward our first 20 external users. Example runs and registrations alone do not count. Joining is free and does not subscribe you to a marketing list.
Report a core issue on GitHub ↗This browser holds your pilot session. If you lose it, contact us to request deletion.
What you get
A card is a starting point.
Make it an informed one.
Know what the signature proves.
Separate verified integrity, missing keys, unsigned cards, and signatures that need attention.
Take evidence with you.
Get concrete next steps. Download the JSON report or run the same policy in your terminal.
Static card inspection only. A valid signature does not establish operator identity or runtime safety. Understand the checks
For your workflow
Same evidence.
In your terminal.
Before a merge. After a deployment.
Whenever you need a second look.
# Install the published CLI archive
npm install -g https://scan.agentcollusion.ai/downloads/agent-card-scanner-0.5.1.tgz
# Inspect a public agent
agent-card-scanner check your-agent.com \
--format text
# Keep local files offline
agent-card-scanner verify agent-card.json \
--url https://your-agent.com/card.jsonBefore you connect
A2A Agent Card checks, explained.
What is an A2A Agent Card?
An Agent Card is a JSON document that describes an agent using the Agent2Agent (A2A) protocol. It advertises information such as capabilities, interfaces, skills and authentication requirements. Some cards also carry a cryptographic signature.
Can I check an agent that is already public?
Yes. Enter its public domain or exact Agent Card URL. The agent does not need to enroll. The scanner retrieves the public card and supported public keys without invoking agent tasks.
Can I compare multiple agents?
The CLI accepts a list of public hosts or card URLs. It collects per-target observations, checks cards, and compares verified signing-key fingerprints and declared provider or authentication information. Its JSON report includes candidate groups and the signals linking each pair. These are leads for investigation. The Web form checks one card at a time. See how the comparison works.
Is a valid signature proof that an agent is safe?
A valid signature establishes integrity under the selected key policy. It does not prove operator identity, authorization or runtime safety. The result separates signature evidence from checks of the card's declarations.
Can I keep private JSON files on my device?
Yes: use the CLI's verify command, which is offline by default. Pasted or uploaded Web JSON is processed on the service. Read about data handling.
Is the scanner free, and does it run in CI?
The public beta is free and requires no account. The CLI supports JSON output and documented exit codes for automated checks. The Web service has launch rate limits; the CLI runs in your own environment.
Supported checks and signature policy ↗How scanning and verification work ↗検査・比較のしくみ（日本語）↗
Built for a world of agents.
From AgentCollusion’s research into the relationships between autonomous systems.
Explore the research