Summary

Aligns the MCP recipe, MCP server docs, and the HTTP transport startup log with the current public API and versions. Documentation and one log-string change only; no protocol surface, wire format, schema, or runtime behavior changes.

Scope

• docs/SOLUTIONS/mcp-tool-call-receipts.md
• docs/specs/INTEROP.md
• packages/mcp-server/README.md
• packages/mcp-server/src/http-transport.ts (startup log string only)

Explicitly not changed: tool schemas, the _meta carrier format, transport behavior, any package exports.

Changes

• The MCP recipe now uses the real exported API: attachReceiptToMeta, extractReceiptFromMetaAsync, and computeReceiptRef, with the current single-options-object issue() signature. The attach example preserves the full MCP result (content, structuredContent, isError). The short snippet stays minimal and points production tool-call facts to registered extension/profile usage through extensions; the runnable example is referenced as the source of truth. The recipe's dependency list and install command match the snippet imports, and the stated outcome matches what the minimal record binds.
• docs/specs/INTEROP.md states the correct MCP tool count (5) and enumerates the tools.
• packages/mcp-server/README.md sample context uses the current 0.15.0 server version and 2025-11-25 protocol version, and clarifies that the schema-declared structured-output _meta audit block is separate from the top-level MCP _meta receipt carrier.
• The HTTP transport startup log derives its protocol version from the MCP_PROTOCOL_VERSION constant instead of a hardcoded string.

Validation

• tsc --noEmit for @peac/mcp-server passes.
• Prettier and whitespace checks pass on all four files.
• Grep confirms no stale function names, tool counts, or version strings remain in the touched files.