Can other agents read your agent card?

An agent introduces itself with a card published at /.well-known/agent-card.json. It is the only document another agent reads before deciding to call you. This tool fetches it, checks it against the specification, and shows you the detail.

Readable card, points to review

No required field is missing, but some points deserve attention.

What the card declares

Name: agents.txt Reference Agent
Provider: agents.txt contributors
Agent version: 1.0.0
Protocol version: 0.2
Transport: JSONRPC
Endpoint: https://agents-txt.com/a2a
Card shape: pre-v1.0
Location: standard location
Skills: 4
Response time: 318 ms

Findings

WarningdefaultInputModes[0] is not a media type in the form type/subtypedefaultInputModes[0]
WarningdefaultOutputModes[0] is not a media type in the form type/subtypedefaultOutputModes[0]
WarningCard written in the shape used before v1.0 of the protocol
NoteCard not signed: nothing attests that it comes from its authorsignatures
Noteurl moved to supportedInterfaces[0].url in v1.0url
NoteprotocolVersion moved to supportedInterfaces[].protocolVersion in v1.0protocolVersion

Declared skills

Explain an agents.txt directiveReturns the spec section text for a named directive (Protocols, Authorization, MCP, Skills, A2A, etc.) plus an example and the relevant section number.
- spec
- agents.txt
- documentation
Validate agents.txt and agents.jsonRuns the spec validators against a site's discovery files and returns a compliance report. Delegates to the audit_site MCP tool exposed at mcp.agents-txt.com.
- validation
- audit
- compliance
Explain an announced payment protocolReturns a plain-language explanation of any payment protocol the site declares (x402, mpp, ap2): what it is, what role it plays, where the runtime details live, and how it composes with the others.
- payments
- x402
- mpp
- ap2
- documentation
Summarize a site's agent capabilitiesReads agents.txt and agents.json from a target origin, summarizes the declared payment protocols, authorization scheme, MCP endpoints, skill packages, and A2A AgentCards in plain language.
- discovery
- capabilities
- summary

Show the result

This badge follows your readings: it changes when your card changes. Paste it in your README.

Markdown

[![A2A card](https://kopass.app/a2a/badge/aHR0cHM6Ly9hZ2VudHMtdHh0LmNvbQ.svg)](https://kopass.app/a2a/validator?url=https://agents-txt.com)

HTML

<a href="https://kopass.app/a2a/validator?url=https://agents-txt.com"><img src="https://kopass.app/a2a/badge/aHR0cHM6Ly9hZ2VudHMtdHh0LmNvbQ.svg" alt="A2A card" height="20"></a>

The rules come from the protocol's specification/a2a.proto file, where every required field is marked as such. Nothing is added.

Cards read here feed the KoPass daily reading: 228 agents followed, 214 of which answered on the last pass.

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