docs: accept partial send sandbox evidence

docs/go-mcp-runbook.md

@@ -401,7 +401,34 @@ The package also contains `RECORDING-PACKAGE-MANIFEST.json`, `run-before-recorde
 
 Production `isphere_send_message` remains blocked until the returned package is analyzed.
 
-## 14. Offline capability-test package
+## 14. Returned sandbox package validation
+
+When a returned package comes back, validate it before treating it as evidence:
+
+```powershell
+powershell -NoProfile -ExecutionPolicy Bypass -File scripts\validate-returned-send-sandbox-package.ps1 -PackagePath C:\Users\zhaoy\Downloads\1631.zip
+```
+
+The current partial returned package `C:\Users\zhaoy\Downloads\1631.zip` validates as:
+
+```json
+{
+  "partial_evidence_usable": true,
+  "r6d_gate_pass": false,
+  "production_send_enabled": false,
+  "decision": "partial_use_only"
+}
+```
+
+Use `partial_use_only` to continue local sandbox-only connector-shell and idempotency/audit work. Do not enable production send from a partial package. Full pass still requires after-recorder output and manual send timestamps.
+
+The fixture test for the current partial package is:
+
+```powershell
+powershell -NoProfile -ExecutionPolicy Bypass -File scripts\test-validate-returned-send-sandbox-package.ps1
+```
+
+## 15. Offline capability-test package
 
 Use this second package when you want to test the current capability surface without logging in and without any real send.
 
@@ -440,7 +467,7 @@ Expected final JSON includes:
 
 This package includes `isphere-capability-smoke.exe` and `runs\win-helper\ISphereWinHelper.exe`. It verifies the nine-tool MCP surface, fixture-backed receive/search/file-list behavior, send preview, and the production-send block. It does not log in, click, type, upload, hook, inject, or send.
 
-## 15. Troubleshooting
+## 16. Troubleshooting
 
 - If C# helper build fails, run `scripts\build-win-helper.ps1` directly and check for missing .NET Framework reference assemblies.
 - If `win_helper_version` fails, rerun `powershell -NoProfile -ExecutionPolicy Bypass -File scripts\verify-win-helper.ps1` first.