diff --git a/internal/api/handlers_write_devloop_params_test.go b/internal/api/handlers_write_devloop_params_test.go
index 08e93694..dd886dba 100644
--- a/internal/api/handlers_write_devloop_params_test.go
+++ b/internal/api/handlers_write_devloop_params_test.go
@@ -3,6 +3,7 @@ package api_test
 import (
 	"net/http"
 	"sort"
+	"strings"
 	"testing"
 
 	"github.com/mctlhq/mctl-api/internal/auth"
@@ -60,6 +61,20 @@ var devLoopSubmissions = []struct {
 			"execution_request_id": "xr_0000",
 		},
 	},
+	{
+		// dev_loop.py human-input continuation (mctlhq/mctl-agents#473): the
+		// pinned, correlated investigate step plus the accepted answers.
+		name:      "investigate, human-input continuation",
+		operation: "mctl-agents-investigate",
+		params: map[string]string{
+			"issue_url":             "https://github.com/mctlhq/mctl-api/issues/372",
+			"agent_image":           pinImageByTag,
+			"agent_version":         "issue-investigator@1.54.0",
+			"temporal_workflow_id":  "dev-loop-mctlhq-mctl-agents-494",
+			"temporal_run_id":       "00000000-0000-0000-0000-000000000000",
+			"human_input_responses": `[{"request_id":"hir-0123456789abcdef","request_hash":"sha256:` + strings.Repeat("a", 64) + `","value":"library B","received_at":"2026-10-04T10:00:00Z"}]`,
+		},
+	},
 	{
 		// dev_loop.py investigate step, a published version with a digest.
 		name:      "investigate, pinned by digest",
@@ -218,9 +233,9 @@ var devLoopParamsPendingDeclaration = []struct {
 	param     string
 	value     string
 }{
-	// dev_loop.py human-input continuation; not declared by
-	// cwft-mctl-agents-investigate (mctlhq/mctl-api#372 item 3).
-	{"mctl-agents-investigate", "human_input_responses", `[{"request_id":"hir-0000000000000000"}]`},
+	// human_input_responses (mctl-api#372 item 3) moved to devLoopSubmissions
+	// above once cwft-mctl-agents-investigate declared it
+	// (mctlhq/mctl-gitops#1581).
 	// Loop identity (mctlhq/mctl-agents#461, #451) moved to devLoopSubmissions
 	// above: temporal_workflow_id, temporal_run_id and execution_request_id
 	// are now declared on all three DevLoop operations
@@ -321,3 +336,30 @@ func TestExecuteOperation_UncorrelatedCallerSendsNoCorrelationParams(t *testing.
 		})
 	}
 }
+
+// human_input_responses is opaque to mctl-api, but its shape is pinned: only
+// a JSON array reaches the investigator, and an empty value is an absence,
+// so a run without answers keeps the CWFT's exact argv (mctlhq/mctl-gitops#1581).
+func TestExecuteOperation_HumanInputResponsesShape(t *testing.T) {
+	const issue = "https://github.com/mctlhq/mctl-api/issues/372"
+	t.Run("non-array rejected", func(t *testing.T) {
+		router, exec := newTestRouter(t)
+		w := postAs(t, router, "/api/v1/operations/mctl-agents-investigate/execute", map[string]string{
+			"issue_url": issue, "human_input_responses": `{"request_id":"hir-0123456789abcdef"}`,
+		}, auth.NewServiceUser())
+		assertStatus(t, w, http.StatusBadRequest)
+		if len(exec.submittedParams) != 0 {
+			t.Fatal("a rejected submission reached the executor")
+		}
+	})
+	t.Run("empty omitted", func(t *testing.T) {
+		router, exec := newTestRouter(t)
+		w := postAs(t, router, "/api/v1/operations/mctl-agents-investigate/execute", map[string]string{
+			"issue_url": issue, "human_input_responses": "",
+		}, auth.NewServiceUser())
+		assertStatus(t, w, http.StatusAccepted)
+		if _, ok := exec.submittedParams[len(exec.submittedParams)-1]["human_input_responses"]; ok {
+			t.Error("an empty human_input_responses reached the executor; it must be omitted")
+		}
+	})
+}
diff --git a/internal/operations/registry.go b/internal/operations/registry.go
index f24d6f08..71054671 100644
--- a/internal/operations/registry.go
+++ b/internal/operations/registry.go
@@ -806,9 +806,16 @@ var builtinOperations = []Operation{
 			// DevLoop correlation identifiers (mctlhq/mctl-api#426,
 			// mctlhq/.github#50): dev_loop.py's investigate step sends these;
 			// cwft-mctl-agents-investigate declares all three.
-			// human_input_responses is deliberately NOT declared here: the CWFT
-			// does not declare it (mctl-api#372 item 3), so it stays in
-			// devLoopParamsPendingDeclaration.
+			// Human-input continuation (mctl-api#372 item 3, mctlhq/mctl-agents#473):
+			// dev_loop.py sends the accepted answers as a JSON array once a
+			// human answered a sealed question. cwft-mctl-agents-investigate
+			// declares it since mctlhq/mctl-gitops#1581. Opaque here: the
+			// investigator validates every entry (ids, hashes, bounded values)
+			// before any clone or model call; this only pins the array shape.
+			// OmitWhenEmpty so a run without answers keeps its exact argv.
+			{Name: "human_input_responses", Type: "string", Required: false, OmitWhenEmpty: true,
+				Description: "Optional. JSON array of accepted human-input answers for a DevLoop continuation (mctl-agents#473). Set only by the DevLoop; omit otherwise.",
+				Pattern:     `(?s)^\[.*\]$`},
 		}, append(agentPinParams("issue-investigator"),
 			devLoopCorrelationParams("temporal_workflow_id", "temporal_run_id", "execution_request_id")...)...),
 	},
diff --git a/internal/operations/registry_cwft_params_test.go b/internal/operations/registry_cwft_params_test.go
index edc03761..0350b736 100644
--- a/internal/operations/registry_cwft_params_test.go
+++ b/internal/operations/registry_cwft_params_test.go
@@ -32,6 +32,7 @@ var cwftDeclaredParams = map[string][]string{
 		"issue_url", "agent_image", "agent_version",
 		"work_item_id", "execution_id",
 		"temporal_workflow_id", "temporal_run_id", "execution_request_id",
+		"human_input_responses",
 	},
 	"mctl-agents-implement": {
 		"service", "slug", "force", "max_proposals", "agent_image", "agent_version",