Detailed compatibility matrix
| Provider | Evidence | Create image | Lifetime | Command output | Connection context |
|---|---|---|---|---|---|
| Blaxel | Preview / contract-tested | Runtime image supported | Timeout sent as runtime TTL | Separate stdout and stderr | X-Provider-Workspace |
| E2B | Preview / contract-tested | Template ID supported | Timeout in seconds | Separate stdout and stderr | None |
| Daytona | Launch tier / live-proven | Container image supported | Rounded up to TTL minutes | Combined output in stdout | None |
| Runloop | Preview / contract-tested | Blueprint name supported | Maximum 172800 seconds | Separate stdout and stderr | None |
| Fly.io Sprites | Launch tier / live-proven | Fixed environment | No timeout option | Separate stdout and stderr | None |
OpenAPI 0.8.0 additionally covers AWS AgentCore, ASCII Box, Cloudflare Sandbox, Novita Agent Sandbox, Modal, Smol, and Vercel Sandbox. Their exact create inputs and capability descriptors are available in the generated provider reference. These adapters have keyless contract coverage, not current live credential proof.
Daytona and Fly.io Sprites are the initial launch tier and completed the full persistent lifecycle on private staging on July 28, 2026. All other adapters remain preview until an equivalent current credential smoke is recorded.
Tested upstream contracts
Blaxel
E2B
Daytona
Runloop
Fly.io Sprites
Shared response contract
Sandbox responses expose a normalized ID, provider, status, and metadata. Execution responses expose sandboxId, stdout, stderr, and exitCode. Provider-native IDs remain available atmetadata.nativeProviderId, and provider runtime versions appear at metadata.nativeProviderVersion when available.
Shared error contract
The current stable error code set includes invalid requests and idempotency keys, idempotency conflicts or uncertain outcomes, missing keys, invalid sandbox IDs, provider validation failures, authentication failures, missing sandboxes, rate limits, provider unavailability, provider errors, and internal errors. Provider response bodies are not forwarded because they may contain credentials or customer content.
Compatibility is not failover
A supported adapter means that the lifecycle is implemented and covered by contract tests. Wildflower Computer does not retry on a different provider, migrate an existing sandbox, or promise equivalent performance and pricing.