This page lists what each Harness supports on each placement. Core decides admission from the Harness's engine profile in services/core/internal/engine, and the Runtime that runs the Session must also advertise the operation. The linked contracts define each operation; Harness onboarding describes how a Harness is qualified.
| Status | Meaning |
|---|---|
| Verified | Core admits it, and real-model acceptance through the pinned official client passed on that placement |
| Admitted | Core admits it through the same Runtime path, but no real-model acceptance has run on that placement |
| Rejected | Core rejects the request before execution |
Placements are none (no Environment), hosted (openai_hosted) and self-hosted (self_hosted). Hosted acceptance ran on Docker nodes; E2B and microsandbox run the same Runtime and adapters, and every Verified hosted cell counts as Admitted there. Self-hosted acceptance ran on Linux machines; the self-hosted guide lists the supported platforms. A verified operation is verified on its own, not in every combination with other options; combinations that a profile rejects are listed in the operation's contract.
Execution and input
| Operation | Codex | Claude SDK | MiniMax Code |
|---|---|---|---|
| Text Turns, active input, cancellation, restart and continuation | Verified on all placements | Verified on all placements | Verified on all placements |
| Files and Artifacts | Verified: hosted, self-hosted | Verified: hosted, self-hosted | Verified: hosted, self-hosted |
| Whitespace-only message text | Admitted; delivered unchanged | Rejected | Rejected |
| Inline PNG and JPEG message images | Verified on all placements | Verified on all placements | Rejected |
| Remote image URLs | Rejected | Rejected | Rejected |
Explicit reasoning; service_tier other than auto | Rejected | Rejected | Rejected |
text.verbosity other than medium | Admitted; the native model decides | Rejected | Rejected |
| Public token usage | Measured counters | Null | Null |
Native model parameters and provider protocols per Harness are in model execution.
Tools
| Operation | Codex | Claude SDK | MiniMax Code |
|---|---|---|---|
| Public functions with text results | Verified: none, hosted; admitted: self-hosted | Verified on all placements; object-root schemas only | Rejected |
| Function results with images | Verified: none, hosted; admitted: self-hosted | Verified on all placements; successful inline PNG or JPEG results only | Rejected |
| Structured output | Rejected | Verified on all placements | Rejected |
| Deferred function discovery | Rejected | Verified: none, self-hosted; admitted: hosted | Rejected |
| Disabled web search and programmatic tool calling | Verified: none; admitted: hosted, self-hosted | Verified: none; admitted: hosted, self-hosted | Verified: none; admitted: hosted, self-hosted |
| Enabled web search or programmatic tool calling | Rejected | Rejected | Rejected |
| Service-origin HTTP MCP | Verified: none; rejected elsewhere | Verified: none; rejected elsewhere | Rejected |
| Environment-origin HTTP MCP | Verified: hosted, self-hosted | Verified: hosted, self-hosted | Verified: hosted, self-hosted; allowed_tools null and required false only |
| HTTP MCP bearer credentials | Verified | Verified | Verified |
| Required MCP initialization | Verified | Verified | Rejected |
| Subagents | Verified: hosted; admitted: none, self-hosted | Verified: hosted; admitted: none, self-hosted | Verified: hosted; admitted: none, self-hosted |
| Subagents together with functions or HTTP MCP | Rejected | Rejected | Rejected |
Claude structured output requires a single Agent, medium verbosity and no Skills, Plugins, capability directories, MCP or tool_search. Claude deferred discovery requires a single Agent, only function tools besides tool_search and the disabled controls, no Skills, Plugins or capability directories and no structured output. Claude on a workspace placement needs the packaged bridge features for each operation (workspace_functions, workspace_structured_output, workspace_tool_search, workspace_mcp_http).
Environment preparation
These operations need a workspace, so they apply to hosted and self-hosted placements only.
| Operation | Codex | Claude SDK | MiniMax Code |
|---|---|---|---|
| Initial files, setup commands, Skills and Plugins | Verified: hosted, self-hosted | Verified: self-hosted; admitted: hosted | Verified: self-hosted; admitted: hosted |
| Capability directories | Admitted | Admitted | Admitted |
| npm and Python packages | Admitted | Admitted | Admitted |
packages.system | Rejected | Rejected | Rejected |
Network disabled or restricted | Rejected | Rejected | Rejected |
| Plugin MCP over stdio | Verified: hosted, self-hosted | Verified: self-hosted; admitted: hosted | Verified: self-hosted; admitted: hosted |
| Plugin MCP over HTTP | Admitted, with literal headers or HTTPS bearer | Admitted, anonymous or HTTPS bearer | Verified: self-hosted; admitted: hosted; anonymous or HTTPS bearer |