APort vs E2B
E2B isolates code; OAP decides whether the agent was allowed to request that code execution under policy.
E2B’s sandboxes reduce blast radius for arbitrary code and tool use, a containment layer cited in agent security surveys.
Sandboxing does not replace recipient allowlists, spending limits, or MCP tool allowlists. OAP encodes those semantics and fails closed when context is missing.
| Comparison point | OAP / APort | E2B |
|---|---|---|
| Primary control | Semantic authorization (who may do what, with what limits). | Kernel-isolated execution environment for agent code. |
| Startup / perf | Milliseconds policy evaluation; no VM boot. | ~150 ms-class sandbox startup (per cited literature). |
| Business policy | Currency limits, merchant allowlists, audit codes, MCP scopes. | Infrastructure limits (CPU, network egress, FS) inside VM. |
| Complements | Run OAP hooks outside the sandbox, E2B inside for code-heavy tools. | Pair with OAP to keep policy decisions out of the guest. |
Use E2B when
- You execute untrusted code from agents frequently
- You need strong isolation for arbitrary Python/Node workloads
- You want hosted sandboxes without building your own Firecracker farm
Use OAP / APort when
- You must enforce org policy before spawning sandboxes or calling APIs
- You need signed decisions independent of infrastructure vendor
- You use MCP and shell tools outside a single sandbox boundary
Why teams choose OAP / APort
Policy outside the VM
Decisions are made before resources are allocated, reducing cost and abuse.
Works for non-code tools
Payments, messaging, and MCP calls may never touch a sandbox; OAP still applies.
Portable across hosts
Same passport works whether the tool runs locally, in E2B, or on-prem.
Sources
Read these sources alongside the table and use-case tradeoffs. The comparison is APort's interpretation; each source describes its own system.
- E2B documentationProvider's description of its own approach.
- Before the Tool CallOAP design and related authorization approaches. This comparison is APort's interpretation.
- Open Agent Passport specificationPassport, policy and decision contracts.