Two Anchor customers look like they operate in unrelated domains. One sells enterprise identity governance; the other sells browser infrastructure for AI agents. Both now build on the same protocol surface, and it is moving fast enough to make any publication that ignores it stale within a quarter.
MCP's June 2025 authorization spec set the floor: every access token must name the specific server it targets, servers must reject tokens not issued for them, and passing a received token downstream to another API is explicitly flagged as an anti-pattern. That's the shared constraint.
Okta extended the spec toward centralized governance. Its Cross App Access extension, listed as stable in MCP on June 18, 2026, lets IT authorize connectors once, scope permissions by role, and revoke through a single identity provider.
TinyFish addressed a different surface of the same problem. Vault isolates credentials at the browser level so the model navigates login flows but never touches the raw secret. TinyFish itself notes Vault doesn't cover post-login risks like session misuse, which sit in exactly the territory MCP's token-validation rules and Okta's centralized revocation are designed to address.
Note the convergence. Both companies' product positioning depends on a protocol surface whose enterprise layer went stable one week ago. A publication that treats this substrate as background will lose currency before its next refresh.
What the spec requires: Tokens must include a resource parameter identifying the target MCP server. Servers must validate tokens were issued specifically for them. Tokens travel only in HTTP Authorization headers, never in query strings. Token passthrough is banned.
What the spec leaves open: Authorization server implementation and hosting. Whether to support dynamic client registration. How clients choose among multiple authorization servers. SSRF protections for server-side deployments.
How fast this moved:
- June 18, 2025 — MCP auth spec classifies servers as OAuth Resource Servers, adds audience-bound token requirement
- June 23, 2025 — Okta announces Cross App Access
- Nov 25, 2025 — Okta says Cross App Access incorporated into MCP as Enterprise-Managed Authorization
- June 18, 2026 — Extension listed as stable; Okta named featured identity provider for Claude Enterprise beta
Key caution: MCP authorization is optional and applies only to HTTP-based implementations. STDIO transports handle credentials differently. Enterprise-Managed Authorization is opt-in and requires client-level support.