Aembit vs. Descope vs. WorkOS: Choosing an AI Agent Identity Platform

Aembit sits between an agent and the resources it calls as an independent broker. Instead of a workload holding a long-lived API key or a stored secret, Aembit issues a short-lived, task-scoped credential at the moment of the call, across AWS, Azure, GCP, on-premises systems, and SaaS APIs, using OAuth, OIDC, SPIFFE, or Kerberos depending on the target. For agent-specific traffic, Aembit adds an MCP Identity Gateway that authenticates an agent's connection to an MCP tool server through what it calls a Blended Identity, combining the agent's own machine identity with the human or tenant context it is operating under, then applying policy and exchanging tokens through a single auditable data plane. The design goal is that the agent itself never touches a durable secret; every call gets a fresh, narrowly scoped credential brokered at request time, and policy can incorporate real-time context such as a device's security posture (Aembit integrates with CrowdStrike for this) or exposure signals (via a Wiz integration).

Descope's architecture starts from the other end. It is a full CIAM platform, passwordless login, SSO, MFA, user and tenant management, and it extended that base with two agent-relevant capabilities. Outbound Apps let an application obtain a scoped OAuth token so an agent can call a third-party API (a CRM, a calendar, a payments provider) on behalf of a user or tenant without the application ever holding that provider's long-lived credential directly. Inbound Apps and related tooling cover the reverse direction, authenticating callers into an MCP server the organization exposes, including Dynamic Client Registration (DCR) security, a detail that matters because DCR is the part of the MCP OAuth flow most implementations get wrong. The throughline is that Descope treats agent credentialing as an extension of the same identity flows it already runs for human users, rather than as a separate workload identity product.

WorkOS takes a third approach: authorization as a decision layer, deliberately separate from execution. Fine-Grained Authorization (FGA) models resources in a hierarchy so permissions can be scoped to a specific project, repository, or document rather than a tenant-wide role, and answers access-check queries fast enough (WorkOS states sub-50ms p95) to sit in the hot path of an agent's tool calls. FGA by itself is a yes/no and scope decision, not a place to store a token. That is what Vault is for: an encryption key management product that stores OAuth tokens, API keys, and other secrets using envelope encryption, with options for WorkOS-hosted keys, customer-managed keys through AWS KMS, GCP KMS, Azure Key Vault, or HashiCorp Vault, or a full bring-your-own-key model. An agent's credential path on WorkOS therefore runs through two products working together, FGA deciding what an agent may do and Vault holding what it needs to do it, rather than one integrated flow.

Aembit is SaaS-delivered (SOC 2 and ISO 27001 certified per its own materials) and connects out to the workloads and cloud accounts it brokers credentials for; it does not require agents to be rearchitected around a proxy, though every integration point (a cloud provider, a SaaS API, an MCP server) needs to be registered as a target the broker knows how to authenticate to. Descope deploys as a hosted CIAM tenant, with Outbound and Inbound Apps configured inside that same tenant alongside the organization's existing user auth setup, so a team already running Descope for customer login adds agent flows as new app types rather than standing up separate infrastructure. WorkOS deploys FGA and Vault as separate, composable products against an existing WorkOS AuthKit or SSO tenant; Vault specifically supports customer-managed and BYOK key models for teams with data residency requirements, which is a heavier but more controllable setup than accepting a fully vendor-hosted key.

Aembit's integration surface is aimed at infrastructure and security posture: cloud providers (AWS, Azure, GCP), secrets managers, SaaS APIs, and security tooling like CrowdStrike and Wiz for contextual policy signals. Descope's integration surface reflects its CIAM roots, dozens of identity providers, SSO connections, and a broader partner ecosystem for human auth, with Outbound Apps extending that same connector model to third-party APIs an agent needs to call. WorkOS's integration story runs through its existing enterprise-readiness catalog, SSO and Directory Sync connections to the identity providers a B2B customer's IT admin already runs, plus FGA and Vault as add-on products layered on top; none of the three publishes an integration count specific to AI agent tool-calling that would let a team compare breadth directly, so this is a point worth testing against the actual APIs and MCP servers a given deployment needs to reach rather than trusting a marketing list.

None of these is a drop-in change; all three require the team building the agent to change how it fetches and uses credentials, not just configure a vendor console. Aembit's heaviest lift is registering every target system (each API, each MCP server, each cloud resource) as a policy target and defining the contextual conditions under which an agent may reach it, plus rewriting the agent's tool-calling code to request a broker-issued credential per call instead of reading a stored key. Descope's lift is lighter for a team already on Descope for user auth, since Outbound Apps reuse existing tenant and consent infrastructure, but heavier for a team adopting Descope purely for agent credentialing, since it means onboarding a full CIAM platform to get the agent-specific slice. WorkOS's lift is split across two products: modeling the resource hierarchy and relationships FGA needs to make scoped decisions, and separately deciding a key management model for Vault (hosted, customer-managed, or BYOK) before any token can be stored. Across all three, the work that does not show up in a demo is instrumenting the agent's own code to call the credential-issuance or authorization-check API at the right moment, every time, instead of falling back to a cached secret when the network call is inconvenient.

Aembit publishes self-serve pricing for both of its product lines. Workloads pricing (for service-to-service, non-agent use) runs a free Starter tier (10 workloads, 10 access policies, 24-hour log retention), a Teams tier at $20 per workload per month scaling from 10 to 50 workloads, and custom Enterprise pricing. Its Agentic AI pricing line runs a free Starter tier (3 AI agents, 5 MCP authorization policies, 24-hour log retention), a Teams tier at $20 per agent per month scaling from 10 to 500 agents with 7-day log retention, and custom Enterprise pricing for unlimited agents and policies with 24/7 support. These are list prices as published; confirm current figures directly before budgeting, since vendor pricing pages change.

Descope also publishes tiered self-serve pricing: Free Forever at $0 (7,500 monthly active users, 10 tenants, 3 SSO connections), Pro starting at $249 per month billed annually (10,000 MAUs, 35 tenants, 5 SSO connections, CI/CD integration), Growth starting at $799 per month billed annually (25,000 MAUs, 100 tenants, unlimited federated apps, SCIM provisioning, HIPAA BAA availability), and custom Enterprise pricing above that. Agent-specific usage is metered separately from the MAU-based tiers: machine-to-machine exchanges are priced apart from user counts, Outbound Apps and Connections use a Monthly Active Token (MATK) meter, and Inbound Apps use a Monthly Active Consent (MAC) meter. The published tier pages describe these meters by name but do not list a flat per-unit rate for MATK or MAC in what we could confirm, so the actual per-agent or per-token cost for heavy agentic use needs a direct pricing conversation rather than an assumption based on the base tier price.

WorkOS is the least transparent of the three on list pricing for the agent-relevant products specifically. WorkOS describes its overall pricing philosophy as usage-based with no per-seat fees, and states that FGA is billed on relationship-check volume with flat rates for the SSO and Directory Sync infrastructure it depends on, but does not publish a specific per-check dollar figure or a Vault price on its public pricing materials as reviewed for this piece. Treat this as an honest gap rather than an oversight: a team evaluating WorkOS FGA and Vault for agent use should request current numbers directly, since nothing here should be read as an implied cost.

Each platform's biggest strength is close to its biggest limitation, since both come from the same design choice.

There is no single winner here; the right platform tracks what a team already runs and what kind of agent traffic it is actually authorizing. A team whose core problem is non-human credential sprawl, dozens or hundreds of services and agents each holding their own static keys across multiple clouds, gets the most direct value from Aembit, since that is the exact workload identity problem it was built to solve before agents existed as a category, now extended with an MCP-specific gateway. A team already running Descope for customer or workforce authentication that now needs its agents to call third-party APIs (a CRM, a calendar, a payments provider) on a user's behalf gets more leverage from adding Outbound Apps to that existing tenant than from standing up a separate workload identity vendor, since the consent and tenant model is already in place. A team already on WorkOS for B2B SSO and directory sync, building agents that need resource-scoped permissions (this agent can touch this customer's data, not the whole tenant) and a defensible place to store the OAuth tokens those agents use, gets the most out of FGA paired with Vault, particularly if data residency requirements make WorkOS's customer-managed-key options for Vault relevant. None of the three is the better choice in the abstract; the deciding factor is which identity stack a team is already operating and whether the agent traffic in question looks like pure machine-to-machine calling, user-delegated API access, or fine-grained resource permissioning.

All three platforms assume the team has already decided agents should call APIs and tools directly with brokered or vaulted credentials, rather than through a human approving each action in real time. If the actual risk in front of a team is an agent that needs a live human to approve a specific consequential action (an irreversible financial transaction, a production deployment, a legal commitment), none of Aembit, Descope, or WorkOS is primarily built for that in-the-moment approval flow; that is closer to the delegated-authority problem covered by Auth0, Entra Agent ID, and Okta Cross App Access, and mixing the two problem shapes into one vendor evaluation tends to produce a worse fit on both fronts. Separately, if an organization has not yet inventoried which service accounts and static API keys its existing (non-AI) automation already depends on, adding an agent identity platform on top of that unmanaged base does not fix the underlying sprawl, it just adds a new credential type to track alongside the old ones. And if the actual agent population today is small (a handful of internal scripts, not a fleet of customer-facing or partner-facing agents), the operational overhead of standing up any of these three platforms may exceed the risk being managed; tightly scoped service accounts with short rotation windows and centralized logging can be the honest interim answer until agent volume justifies dedicated tooling. For that inventory step, our non-human identity security guide is the place to start before evaluating any vendor.

Run these checks against one real agent workflow the team already operates, not a hypothetical, before committing budget to any of the three.