docs: AGENTS.md grants post-merge release and local install

.claude-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "model-router",
-  "version": "0.42.0",
+  "version": "0.42.1",
   "description": "Route authorized software work through one durable, capacity-aware subscription policy.",
   "author": {
     "name": "toolboxmd",

.codex-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "model-router",
-  "version": "0.42.0",
+  "version": "0.42.1",
   "description": "Route authorized software work through one durable, capacity-aware subscription policy.",
   "author": {
     "name": "toolboxmd",

.grok-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "model-router",
-  "version": "0.42.0",
+  "version": "0.42.1",
   "description": "Route authorized software work through one durable, capacity-aware subscription policy.",
   "author": {
     "name": "toolboxmd",

AGENTS.md

@@ -0,0 +1,14 @@
+# model-router Repository Instructions
+
+Follow the installed AgentsMD global contract.
+
+- Final PR merges stay with the user. After the user merges, Delivery
+  Authority for this repository includes, without another prompt: the
+  resulting GitHub release through the release workflow, and installing that
+  released version on the maintainer's local hosts once Toolybara promotes it
+  to the marketplace (today the Codex plugin that Chromeria's Prism runs:
+  `codex plugin marketplace upgrade`, then
+  `codex plugin add model-router@toolboxmd`), with post-install verification
+  (`bin/model-router --version` in the installed plugin root) and an entry in
+  the maintainer's runbook. Third-party publication still needs explicit
+  authority.

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## [0.42.1] - 2026-09-29
+
+### Changed
+
+- New `AGENTS.md`: after a merge, the release and installing it on the maintainer's hosts need no further prompt
+
 ## [0.42.0] - 2026-09-29
 
 ### Changed

VERSION

@@ -1 +1 @@
-0.42.0
+0.42.1