D7: the builder's ask put is a kept call, a put or note a transport fault kept from the key fails it in that fault's words, and builder_build_again takes a key left building (issue 1966, 1748 note 27, ADR 0668 §1, §2, §5)

The put carries the ask's id as its message id, so it is made again through a deadline and no responders within the bound;
a put or a note that still meets one fails the key as a transport fault, which the builder does not retake by itself
(ADR 0664 §3) and the hand tool does. A key left building with no look holding it (its end never written: "claimed", no
ask) is taken as it stands by builder_build_again, from another builder too.

Claude-Session: https://claude.ai/code/session_01JG73KEq4zoDfM9WtYpcQgZ

modules/mesh-delivery-builder/cmd/mesh-delivery-builder-tools/main.go

@@ -160,10 +160,11 @@ func Tools(r build.StuckReader, askAgain func(key string, value []byte) error, q
 		{Name: build.BuildAgainTool,
 			Description: "Build a failed key again (rebuild a module, build a failed key again): the builder writes the key of module and " +
 				"fingerprint building as a new revision of the same key and asks the build seats, as it does by itself when it looks at a module " +
-				"again (ADR 0429 clause 18). Answers the new revision and the ask id of each build module (go, node, image). Refuses a key that " +
-				"is not failed, and says why: done (nothing to do), or waiting (building or queued: " + build.AskAgainTool + " asks its waiting asks " +
-				"again); a key failed for a reason the builder never retries on the same fingerprint (a pin missing, a version taken, digests that " +
-				"differ) and a fingerprint its module no longer has are refused too. Use it for a key builder_stuck does not show, which failed.",
+				"again (ADR 0429 clause 18). Answers the new revision and the ask id of each build module (go, node, image). Also takes a key left " +
+				"building that no look of the builder holds (its ask never put or its end never written, ADR 0668 §5): an ask the key names and " +
+				"its stream holds is waited for, one never put is put under its id. Refuses a key done (nothing to do) or queued (" +
+				build.AskAgainTool + " asks its waiting asks again), and one the builder is looking at now; a key failed for a reason the builder never retries on the same fingerprint (a pin missing, a version taken, digests that " +
+				"differ) and a fingerprint its module no longer has are refused too. Use it for a failed key, or one builder_stuck shows building with no ask or no step.",
 			Input: map[string]any{"type": "object", "required": []string{"module", "fp", "why"}, "properties": map[string]any{
 				"module": map[string]any{"type": "string", "description": "the module's name"},
 				"fp":     map[string]any{"type": "string", "description": "its new-form fingerprint, src2:<hex>"},