Both govern what AI agents are allowed to do. Permit.io is a fine-grained authorisation platform you embed and model: RBAC, ABAC, and relationship-based access built on open policy engines, with a drop-in MCP gateway. PolicyLayer is a turnkey, MCP-native gateway: deterministic policy on every tool call, with rules already written for your servers. Here is where each one fits.
Permit.io is a platform to build authorisation into systems you operate. PolicyLayer is a ready-made control plane for the MCP servers you already consume.
PolicyLayer is the hosted gateway your MCP traffic runs through. Connect your servers and every tool call is checked against deterministic, deny-by-default policy before it executes: allow, deny, rate-limit, or require approval, with argument-level rules and a per-call audit log. It is MCP-native, ships recommended policy pre-classified across 220,000+ catalogued tools, and needs no policy engine to model or operate.
Permit.io is an authorisation-as-a-service platform for fine-grained access control across apps, APIs, and agents. It is built on open engines (OPA and Rego, with OPAL for real-time policy sync) and supports RBAC, ABAC, and relationship-based access. Its MCP Gateway is a drop-in proxy that adds agent identity, OAuth consent, per-tool authorisation, and audit, with policies modelled in Permit and enforced by policy decision points you run hosted or in your own environment.
A platform you build on, versus a control plane that is ready for your MCP fleet.
| PolicyLayer | Permit.io | |
|---|---|---|
| Primary job | Enforce deterministic policy on every MCP tool call across the servers you run | Provide a fine-grained authorisation layer you embed across apps, APIs, and agents |
| Policy engine | PolicyLayer's own deterministic policy, no engine to operate | OPA and Rego, with OPAL for real-time policy distribution |
| Authoring | Visual editor and JSON; recommended policy ships out of the box | Model RBAC, ABAC, or relationship-based policy (Rego under the hood) |
| Granularity | Per tool and per argument (deny refunds over $1k, block DELETE without WHERE) | Per resource, role, attribute, and relationship; per-tool at the MCP gateway |
| Starting policy | Recommended rules pre-classified across 220,000+ catalogued tools | Model your own policies; the MCP gateway can generate a starting policy from a server |
| MCP coverage | MCP-native: gateway, server and tool directory, per-tool risk classification | MCP Gateway proxy alongside a broader app and API authorisation platform |
| Identity | Per-person and per-agent scoped grant tokens routed through the gateway | Agentic identity bound to a verified user via OAuth, with your IdP |
| Approvals | Allow, deny, rate-limit, or require approval on any call | Access Requests and Approvals product, with embeddable approval UI |
| Audit | Every call logged with the tool, its arguments, and the decision | Decision logs and traces across users, agents, tools, and policies |
| Deployment | Hosted gateway; route your servers through it, no PDP to run | Hosted control plane plus policy decision points you run hosted or self-hosted |
| Best fit | Teams consuming MCP servers who want control without building authorisation | Teams building their own apps and agents who need to embed authorisation |
You route Claude Code, Cursor, or Codex through MCP servers and want one place to enforce and audit policy, without modelling an authorisation system.
Deny a refund over a threshold or a DELETE without a WHERE clause, starting from recommended policy rather than authoring Rego.
PolicyLayer is hosted, with no policy engine or decision points to operate.
A server and tool directory and per-tool risk classification, built for MCP rather than added to a general platform.
You need an authorisation layer embedded across your apps, APIs, and agents, not only at an MCP gateway.
Your model requires a relationship graph and attribute-based rules across many resource types, with a policy engine you control.
You want a single platform governing humans and agents across every system, with a team to model and operate it.
They can complement each other. Permit.io can model identity and authorisation for the apps and agents you build; PolicyLayer enforces deterministic, argument-level policy on the MCP tool calls those agents make against the servers you run.
Whatever your agents touch, the same engine, audit, and access model is doing the work underneath every rule you write.
Rules run as code, not model judgement: argument-level conditions, quotas, deny-by-default. The same call gets the same decision every time.
Writing policies →Your security or compliance team writes and attaches policy without ever holding the upstream credentials or grant tokens.
Roles →Every call is logged with its decision and the rule that fired, attributed to the identity, in an append-only record. Argument values are redacted, never stored.
Logs & security →Upstream secrets are encrypted at rest and injected by the gateway. The agent only ever holds a scoped token.
Logs & security →Every person and agent connects with its own scoped grant. Rotate or revoke any one of them instantly, without disrupting the rest.
Core concepts →Hosted gateway. Point your clients at it, register a server, issue a token. Nothing to install.
Quick start →No. Permit.io is a general authorisation platform you embed and model across apps, APIs, and agents, built on OPA and Rego. PolicyLayer is a turnkey, MCP-native gateway that enforces deterministic policy on every tool call, with recommended rules out of the box and no policy engine to operate.
No. PolicyLayer policies are authored in a visual editor or as JSON, and recommended policy ships pre-classified across 220,000+ catalogued tools. Permit.io compiles policy to Rego or Cedar depending on the engine you choose.
Yes. PolicyLayer evaluates the call and its arguments: deny a refund over a limit, block a DELETE without a WHERE clause, require approval on a specific call. Permit.io governs at the resource, role, attribute, and relationship level, and per tool at its MCP gateway.
Yes. Permit.io can model authorisation for the apps and agents you build, while PolicyLayer enforces deterministic, argument-level policy on the MCP tool calls those agents make.
Deterministic, deny-by-default policy on every MCP tool call: approval gates, per-identity scopes, argument-level rules, and a tamper-proof audit log, with recommended policy out of the box. Route your existing MCP servers through the gateway, live in minutes.
Instant setup, no code required.