fix: keep the last 12 characters of the space ID in the MCP server name

internal/awsdevops/export_test.go

@@ -21,3 +21,8 @@ func ConnectExisting(ctx context.Context, clients Clients, opts SetupOptions) (S
 
 	return ConnectPlan(ctx, clients, opts, plan)
 }
+
+// MCPTools lists every tool in the allowlist, for tests.
+func MCPTools() []string {
+	return append(append([]string{}, mcpReadOnlyTools...), mcpMutativeTools...)
+}

internal/awsdevops/lookup.go

@@ -197,10 +197,18 @@ func agentSpaceARN(region, accountID, spaceID string) string {
 	return fmt.Sprintf("arn:aws:aidevops:%s:%s:agentspace/%s", region, accountID, spaceID)
 }
 
+// mcpServerIDLength is the length to truncate the agent space ID to in the
+// server name.
+const mcpServerIDLength = 12
+
 // MCPServerNameFor is the name of the MCP server that setup registers for an
 // agent space. AWS needs a unique name of letters, digits, "_" and "-", and
-// the ID ties the server to the space.
+// the end of the ID ties the server to the space.
 func MCPServerNameFor(agentSpaceID string) string {
+	if len(agentSpaceID) > mcpServerIDLength {
+		agentSpaceID = agentSpaceID[len(agentSpaceID)-mcpServerIDLength:]
+	}
+
 	return MCPServerName + "-" + agentSpaceID
 }
 

internal/awsdevops/runplan_test.go

@@ -1361,3 +1361,17 @@ func TestMCPServerNameForHasOnlyAllowedCharacters(t *testing.T) {
 
 	assert.Regexp(t, `^[a-zA-Z0-9_-]{1,128}$`, name)
 }
+
+// The name keeps the last group of a UUID space ID.
+func TestMCPServerNameForKeepsTheEndOfTheSpaceID(t *testing.T) {
+	assert.Equal(t, "LaunchDarkly-3f4e5d6c7b8a", awsdevops.MCPServerNameFor("0b9f6c3e-5d7a-4c1e-9a2b-3f4e5d6c7b8a"))
+}
+
+// AWS caps the server name, "_" and a tool name at 64 characters.
+func TestMCPServerNameForLeavesRoomForEveryTool(t *testing.T) {
+	name := awsdevops.MCPServerNameFor("0b9f6c3e-5d7a-4c1e-9a2b-3f4e5d6c7b8a")
+
+	for _, tool := range awsdevops.MCPTools() {
+		assert.LessOrEqual(t, len(name+"_"+tool), 64, tool)
+	}
+}