Drop local approval controls from the Responses API input

[shibayan]

A local tool's approval is resolved in-process, so the provider never issued a matching MCP approval item. Serializing one produced an orphaned mcp_approval_request (server_label: null) or an mcp_approval_response referencing an id the API never saw. The function-calling loop already strips these before the provider sees them, so the hole was the raw OpenAIChatClient path — and FoundryChatClient, which wraps it.

Both cases in toResponsesInput now gate on isHostedApproval, the same server_label test the loop layer uses. Mirrors the upstream Python fix (microsoft/agent-framework#7462), which also documented the hosted/local boundary in the function-calling-loop spec.

The existing hosted round-trip test built its approval response without server_label on the wrapped call; approvalResponse() copies the request's call verbatim, so a real hosted decision always carries it. The test now uses that shape — the same update the upstream fix applied to its own existing test.

Test plan

• New cases: a local approval request/response pair serializes to zero input items, in both stateless and service-storage modes; a hosted pair still round-trips as mcp_approval_request / mcp_approval_response.
• Negative control: with the gate reverted, the new cases fail (measured).
• pnpm check passes.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR fixes a wire-format edge case in the OpenAI Responses API adapter where local (in-process) tool approvals could be serialized as MCP approval items, producing orphaned mcp_approval_request / mcp_approval_response entries that the provider never issued or recognized. The change aligns toResponsesInput with the framework’s existing hosted-vs-local approval boundary (isHostedApproval) and updates tests to reflect the real hosted approval shape.

Changes:

• Gate function_approval_request and function_approval_response serialization in toResponsesInput on isHostedApproval, preventing local approvals from being emitted as MCP wire items.
• Add regression tests ensuring local approvals serialize to zero input items in both stateless and service-storage modes, while hosted approvals still round-trip on the wire.
• Update the hosted approval round-trip test to include server_label on the approval response’s functionCall, matching the behavior of approvalResponse().

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
packages/openai/src/to-openai.ts	Filters approval request/response items so only hosted approvals are serialized into Responses API input.
packages/openai/src/to-openai.wire-fallbacks.test.ts	Adds coverage for local vs hosted approval serialization boundaries across stateless and service-storage modes.
packages/openai/src/hosted-tools.test.ts	Fixes the hosted approval round-trip test fixture to include server_label on the response call.

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