Merge remote-tracking branch 'origin/codex/package-readme-limitations-audit-20260712' into codex/model-experience-readmes-20260712

# Conflicts:
#	docs/cookbook/adding-a-package.md
#	docs/rfc/INDEX.md
#	package.json
#	packages/AGENTS.md
#	packages/bash/bash-sandbox/README.md
#	packages/sandbox/sandbox-local/README.md
#	packages/sandbox/sandbox/README.md
#	packages/session-persistence/session-persistence-sqlite/README.md
#	packages/support/acp-snapshot/README.md
#	packages/ui/app-boot/README.md
#	packages/ui/user-approval/README.md
#	packages/workflow/tool-workflow/README.md

packages/timeout/timeout-policy/README.md

@@ -38,3 +38,8 @@ The derived signal only **notifies**; termination stays with the tool and the ca
 ### Composing with other `tools/execute` wrappers
 
 Multiple `tools/execute` listeners compose by cordis registration order. Combined with a future retry/sandbox/metrics wrapper, registration order chooses the semantics — "timeout covers the whole retry operation" (timeout registered outer) versus "timeout covers each attempt" (timeout registered inner).
+
+## Known Limitations and Deferred Work
+
+- **Cooperative, never a hard kill** — the deadline only notifies via `exec.signal`; a tool that ignores the signal does not stop on timeout (see § Cooperative, not a hard kill).
+- **No blanket budget** — only tools that declare `timeoutMs` on their `ToolDefinition` get a deadline; there is no registry-wide default for undeclared tools (the shipped `bash`/`read`/`write`/`edit` deliberately declare none).