An agent identity provider does for AI agents what Google does for people at a sign-in button: it vouches for who is signing in, in a form any app can check. This post defines the term, answers whether you can add one to the login you already run, and sets out what the five current options issue and where each one works.
An agent identity provider is an OpenID Connect issuer whose subjects are AI agents rather than people: it signs a token that names the agent, and apps verify that token the way they verify any sign-in. You can add one on top of your existing login, because to your auth platform it is just another custom OIDC provider.
The term is new enough that it gets stretched. Some products called agent identity are really permission systems, some are directories inside one company, and some are protocols for how an agent registers with an app. They are all useful, and they don't all answer the same question. For a developer deciding what to add, the useful test is concrete: what does the product issue, who can check it, and does it slot into the login you already have or ask you to move?
What is an agent identity provider?
An agent identity provider is the party that vouches for an agent at sign-in. It holds the agent's enrollment, checks the agent's proof when it signs in, and hands the app a signed token with a stable identifier for that agent. The comparison of AI agent authentication platforms ranks the wider field; this post stays on what the term means and whether it layers.
The difference from an ordinary identity provider is the subject. A human identity provider's subjects are people, so an agent using a person's login is indistinguishable from the person. An agent identity provider's subjects are agents, and a good one says so in the token and tells the app who is accountable for the agent.
Can you add agent identity on top of your existing provider?
Yes, if the agent identity provider speaks standard OpenID Connect, because your existing provider already knows how to trust an outside OIDC issuer. Custom providers are a standard feature of hosted auth, and an agent issuer fits that slot next to Google and GitHub.
AgentID, our sign-in for AI agents, works this way. It adds to Clerk, Supabase, Auth0, Better Auth, Auth.js v4 or any OIDC stack, and on most of those it is configuration rather than code. Your users keep signing in as they do today; agents get a button of their own, and the tokens they bring mark them as agents, so your code can treat the two differently. How an AI agent proves its identity with AgentID shows exactly what your app receives.
Layering also means the agent side is someone else's problem to solve, not yours. The provider runs enrollment, holds the proof and publishes the keys; your app only checks a signature and reads claims, as it already does for people. Not every option layers like that. Some live inside a platform you would have to adopt, which is the right trade if you already run that platform and the wrong one if you don't.
What do the current options issue, and where do they work?
The five current options issue different things and work in different places. Match that to your situation first, because a product that only works inside a tenant you don't run is out before features matter.
| Option | What it issues | Where it works | Status |
|---|---|---|---|
| Auth0 for AI Agents, Agent as Principal | Agents as "first-class identities in Auth0, distinct from human users and traditional M2M clients" | Inside your Auth0 tenant | Early Access |
| Microsoft Entra Agent ID | Agent identities that "authenticate using tokens issued by their agent identity blueprint" | Inside your Entra tenant | Generally available since April 2026 |
| Okta Agent SSO | "Short-lived, identity-governed tokens in place of stored credentials" | For agents that support Cross App Access, inside Okta SSO | Generally available since August 2026 |
| WorkOS auth.md | "A scoped access token tied to the user, short-lived and revocable", issued by the app | No WorkOS account required | Released May 2026 |
| AgentID | An ES256-signed OIDC id_token naming the agent, with owner claims for registered apps | Adds to Clerk, Supabase, Auth0, Better Auth, Auth.js v4 or any OIDC stack | Live; free for apps |
Three of these are not identity providers in the narrow sense, and it helps to say so. WorkOS auth.md is a registration protocol: a file an app hosts that tells agents how to register on behalf of a user, where the app issues the credential. Okta and Entra govern agents inside a directory. Auth0's Agent as Principal is the closest to an agent identity provider inside a platform, and AgentID is the one built to be consumed by apps outside any shared platform.
How do you choose between them?
You choose by where your agents live and where they need to be recognized. The short version, as condition and answer:
- Your agents are internal and your company runs Entra: Microsoft Entra Agent ID, which records a Sponsor who provides "business accountability" for each agent.
- Your workforce runs Okta and your agents support Cross App Access: Okta Agent SSO.
- Your app runs on Auth0 and you are securing agents you build for your users: Auth0 for AI Agents.
- You want agents to register with your app on behalf of their users: WorkOS auth.md.
- Agents you didn't build arrive at your app from outside and you want to know which agent and whose: AgentID.
These aren't exclusive. An agent can hold a directory identity at the company that runs it and an AgentID for the public apps it signs in to, and auth.md's agent verified flow is designed around an agent's identity provider vouching for it. What the agent needs underneath all of them is an address of its own, which is where an email address for your AI agent's signups starts.
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