Top 7 best auth and agent-friendly providers in 2026

If you are building modern SaaS, AI agents, MCP servers, or heavy CLI workflows, "user auth" suddenly looks different.

You are no longer only logging in humans. You are also:

• Letting headless agents call APIs on behalf of a user
• Issuing machine-to-machine tokens for background jobs and tools
• Managing personal access tokens and API keys for developers
• Securing CLIs that run on laptops, servers, or CI

This article looks at seven auth providers that work well in this agent-heavy world, and what they are actually good at in practice instead of just repeating marketing lines.

What makes an auth provider "agent-friendly"?#

Before listing names, it helps to be clear about the evaluation criteria:

1. Protocol coverage

   Agents open up an entire ecosystem. To participate in the AI landscape, you need open standards and solid protocol support and that's the foundation.

   • Solid OAuth 2.x and OIDC support
   • Client credentials (M2M) flows
   • Device authorization flow for CLI and smart devices

2. Machine-auth building blocks

   • M2M apps and service accounts
   • Short-lived access tokens and refresh strategies
   • Personal access tokens or API keys for developer tools

3. Org and tenant awareness

   Whether you're building a SaaS product or agents, you will eventually need multi-tenancy and enterprise-grade capabilities. Agents often operate inside an organization, so your tokens must carry org or tenant identifiers. That way, the agent always knows which workspace or project it is acting on.

4. Developer experience

   SDKs, docs, example code for CLIs and agents, good dashboard UX, and transparent pricing. Being able to experiment fast matters more than yet another fancy diagram.

5. Hosting and compliance

   SaaS, self-host, or hybrid, depending on your risk and data residency needs.

With that in mind, here are seven providers that are worth serious consideration in 2026.

1. Auth0 (Okta Customer Identity Cloud)#

Auth0 is still one of the default choices if you want something that covers almost every OAuth edge case.

Why it works for agents

• Mature machine-to-machine (M2M) support, based on OAuth client credentials, aimed at servers, daemons, CLI tools, and IoT devices.
• Built-in device authorization flow that works well for CLIs. You show a verification URL and a short code in the terminal, the user approves in a browser, and the CLI continues with an access token.
• Robust authorization and access control for agents.
• Rich rule and hook system for adding custom logic before and after token issuance.
• Security features like MFA, CAPTCHA, and step-up verification protect both human users and agents when performing sensitive actions.

Where it fits

• You already live in the Okta ecosystem, or you need broad protocol coverage, social logins, enterprise SSO, and advanced policies.
• You have a mix of web and mobile apps, plus a few CLIs and background workers, and you want one system to handle all of them.

Trade-offs

• Cost and complexity are not small. For lean AI infra teams, over-configuring Auth0 is a real risk.
• Some teams end up writing a lot of glue code around rules and actions to get behavior they want.

2. Logto#

Logto positions itself as "modern auth infrastructure for SaaS and AI apps", with a strong focus on developers and open source.

Why it works for agents

• Full OAuth 2.1 and OIDC support, including multi-tenancy, enterprise SSO, and RBAC, which is very useful when your agents operate across tenants or organizations.
• Clear product thinking around PATs, API keys, and M2M and how each should be used in real systems, including CI, background jobs, and developer tools.
• Open source core, which makes it attractive if you want to self-host or deeply customize your auth.

Where it fits

• AI-heavy SaaS products that want multi-tenant RBAC plus agent-style automation on top.
• Teams that prefer an open source stack but do not want to build OAuth and OIDC from scratch.
• Its enterprise-ready capabilities are often underestimated: flexible multi-tenancy support, strong authorization controls, private instance deployment, and tailored authentication solutions.

Trade-offs

• The ecosystem is younger than Auth0 or the large cloud vendors, so you will find fewer "copy and paste from StackOverflow" answers.

3. Clerk#

Clerk started as an authentication solution built for modern React apps, and quickly became popular in developer communities thanks to its polished UI components and smooth developer experience. Its primary strength is not deep identity infrastructure, but rather how easily developers can integrate authentication into their applications.

Why it works for agents

• Excellent frontend developer experience, useful when your product includes both human UI and agent-driven workflows.
• Supports essential authentication capabilities like machine-to-machine, multi-tenancy, and even billing integration.
• Recently raised a Series C round led by Anthropic, signaling future investment in agent authorization and infrastructure.

Where it fits

• Ideal for teams building heavily on Next.js or similar stacks, who want authentication integrated with minimal effort.

Trade-offs

• More focused on frontend and application-layer needs than on core identity infrastructure. Depending on your architecture, that can either simplify your work or limit flexibility.

4. Stytch#

Stytch is well known for passwordless flows, but has quietly built solid M2M and OAuth support for backend and CLI use cases.

Why it works for agents

• Clear guides and APIs for machine-to-machine authentication, using OAuth client credentials, with scopes and permissions for service clients.
• Good documentation around device code and other OAuth flows, including how to handle devices without a full browser.
• Strong B2B organization model that lets agents act for a specific organization and tenant in your product.

Where it fits

• You like Stytch's passwordless and B2B story and want to expand into background jobs, CLIs, and agent actors without switching auth providers.
• You need an identity layer that can grow from "simple login" to complex B2B and agent use cases.

Trade-offs

• Stytch is still more often chosen for human user login than pure infra, so some agent-heavy patterns may require your own conventions.
• As with any flexible B2B auth model, you will spend time modeling orgs, members, and roles correctly.

5. Descope#

Descope is an external IAM platform that started with customer and B2B auth, then extended into agentic identity for AI agents and MCP servers.

Why it works for agents

• Marketing and product direction that explicitly mention agents and MCP ecosystems, not just humans.
• Visual workflows plus SDKs, aimed at rapidly assembling identity journeys across customers, partners, and agents.
• Full OIDC and SAML support, which helps when agents need to plug into existing identity providers or act in enterprise environments.

Where it fits

• You want to treat agents as first-class identities in the same system as customers and partners, and you like the idea of drag and drop flows for those identities.
• You are building something like an "agent marketplace" or a platform where external agents need controlled access.

Trade-offs

• The visual-workflow approach is powerful, but complex setups can become hard to reason about if you do not document them.
• Pricing and positioning are more "enterprise external IAM" than "tiny open source project", so small infra teams should run the numbers.

6. Supabase Auth#

Supabase Auth is based on the open source GoTrue server. It issues JWTs and is deeply integrated with Postgres.

Why it works for agents

• Simple JWTbased auth server that can be self-hosted and extended. Good when you want to own your auth in the same environment as your database.
• Clear API key model with public and secret keys, which maps well to service tokens and internal automation if used carefully.
• Management APIs that let you generate tokens and integrate with other infra components.

Where it fits

• You already use Supabase for database, storage, and edge functions, and you want to keep auth in the same ecosystem.
• You are comfortable managing your own secrets, RLS, and key rotation, and you prefer open source control over a large SaaS vendor.

Trade-offs

• Supabase does not support acting as an OpenID Connect (OIDC) Provider, which means you cannot use Supabase to federate identity to other system
• It doesn't provide a strong architectural foundation for authorization. If you need flexible access control or a robust multi-tenant structure, you may find yourself building a lot on your own.

7. WorkOS#

WorkOS is known for making enterprise SSO and org management easier. In the last few years it has invested more into M2M applications and OAuth client credentials flows.

Why it works for agents

• First-class M2M applications that use OAuth client credentials to obtain short-lived access tokens (JWTs) for APIs and services.
• Well-designed SDKs and APIs for enterprise SSO, SCIM, and directory sync, which matters when agents must act inside corporate environments with strong identity rules.
• Clear story around API keys versus M2M applications and when to use each.

Where it fits

• Your product is enterprise first, with SSO, SCIM, and complex org structures, and agents are a new layer on top.
• You want your agent auth design to align with how your human users already authenticate into the platform.

Trade-offs

• WorkOS shines once you really care about enterprise customers; for small hobby projects it may feel heavy.
• You will likely combine it with your own internal permissions system and policy engine.

How to choose for your agent stack#

A few practical patterns that show up repeatedly:

1. If you are early stage and want open source control

   • Shortlist: Logto, Supabase Auth
   • Good for: tight infra control, self-hosting, building custom agent runtimes or CLIs.

2. If you are a SaaS product mixing human UI and agents

   • Shortlist: Logto, Clerk, Stytch, Descope
   • Look for: org-aware tokens, M2M support, and a clean way to unify user identities and agent identities.

3. If you are enterprise first

   • Shortlist: Auth0, WorkOS, Descope
   • Look for: SAML, SCIM, directory sync, strong auditing, and clear token lifecycles for both humans and agents.

4. If you already picked a provider for users

   Start by asking "Can we represent agents as first-class clients and issue proper M2M or PAT-like tokens from the same system?" Switching providers just for agents often creates more complexity than it removes.